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Part I Mapping the Terrain, 4 Experts, Partisans, and Hired Guns

From: Ethics in International Arbitration

Catherine A. Rogers

From: Oxford Legal Research Library (http://olrl.ouplaw.com). (c) Oxford University Press, 2023. All Rights Reserved. Subscriber: null; date: 06 June 2023

(p. 139) Experts, Partisans, and Hired Guns

Everything we hear is an opinion, not a fact.

Everything we see is a perspective, not the truth.

Marcus Aurelius

For every expert there is an equal and opposite expert;

but for every fact there is not necessarily an equal and opposite fact.

Thomas Sowell

4.01  Expert witnesses are a fixture in modern international arbitration.1 Most sizable cases are dominated by complex questions, such as economic trends in energy markets, the causes of engineering failures, the relationship between obscure biotechnology patents, projected profits, and the like. As the number and range of complex legal questions in transnational disputes have increased, reliance on expert witnesses has also increased. They are now considered essential to decipher and distil various types of information for arbitral tribunals. The consequence of this trend is that expert witnessing in international arbitration is a multi-billion dollar industry for the experts.2 It is also an enormous expense for parties.

4.02  Despite the importance of expert witnesses, their ethical obligations have until recently been systematically neglected. In international arbitration, the issue of expert ethics raises many of the same problems analysed in Chapter 2 regarding counsel ethics, but also some unique new ones.3 For example, similar to counsel ethics, there are significant national legal and cultural (p. 140) differences regarding the nature and function of expert witnesses in arbitral proceedings. In some systems, most notably the United States, Australia, and Canada, parties select, compensate, and coordinate with expert witnesses, including communicating with them before they testify.4 In many other jurisdictions, such as Germany, France, and the Netherlands, expert witnesses are generally appointed directly by, and function as an ancillary to, the adjudicatory decision-maker.5

4.03  When these different national traditions, or expert witness archetypes, are used by opposing parties in a single international arbitration, the problems are obvious. As one commentator posits, perhaps only rhetorically: ‘If one side in the dispute approaches expert witness preparation as an extension of the advocacy process, while the other side adopts notions of impartiality… and the three arbitrators themselves hold to widely different notions of what is proper, is there a level playing field for all participants in the dispute resolution process?’6

4.04  Compounding these comparative differences and the fairness concerns that they raise, the ethics of experts are generally not effectively regulated even within individual national legal systems. To put the problem more bluntly, unlike lawyers, most legal systems do not specifically regulate expert witnesses at all. The main reason for this regulatory gap is that expert witnessing is not, in itself, an occupation or profession. Expert witnesses are most often individuals who belong to an established profession (accounting, engineering, etc.). They lend (or more literally rent) their expertise to an adjudicatory process because an issue in dispute is too complex to be fully understood or resolved without expert guidance. Expert witnesses are, however, only ‘moonlighting’7 from their primary occupations.8

4.05  For these reasons, with a few notable exceptions in England, Australia, and Canada (discussed in greater detail later), experts are not directly regulated by national legal systems when they act as witnesses.9 In the absence of formal regulation, the most immediate source of guidance regarding proper conduct of experts is the body that regulates the underlying professions to which they belong. That guidance, however, is necessarily focused on those experts’ performance of the primary tasks of their chosen professions as accountants, engineers, and the like. Only rarely do those professional regulatory bodies aim at regulating their members when they serve as expert witnesses in adjudicatory settings.10

(p. 141) 4.06  While ethical regulation of expert witnesses is almost non-existent, the costs of unethical expert witnessing can be quite high. Experts are used in an overwhelming majority of cases in both national courts and international arbitrations.11 Experts command high fees, which often represent a substantial expense for parties. In addition, tribunals can expend substantial unnecessary time and effort to sort through unreliable testimony.12 Even with that extra expenditure, perhaps the most problematic cost is tribunals’ diminished ability to reach accurate substantive conclusions when forced to sort through misleading expert testimony.13 For these reasons, the ethical conduct of expert witnesses is a topic that has recently and increasingly captured the attention of international arbitration commentators.

4.07  This chapter surveys the challenges of expert ethics in international arbitration. It begins by examining the comparative differences in the nature and purpose of expert testimony in national legal systems. Although historical practices regarding experts are deeply embedded in particular systems, they also garner significant critiques, both from inside and outside the different systems. Section A surveys these national procedures for expert witnessing, while Section B provides an overview of expert witness practice in international arbitration. Finally, Section C previews the theory of self-regulation, developed more extensively in Chapter 6, through proposed reforms for expert witnesses to be developed by the international arbitration community.

A. Comparative differences in expert witnessing

4.08  Chapter 2 explored the cultural differences and ethical regulations that pertain to attorneys when engaging in pre-testimonial communication with witnesses. Several analogous cultural differences manifest themselves in systems’ treatment of expert witnesses. This section examines, in Subsection 1, the national differences in expert witnessing. Subsection 2 examines the criticisms of these various national traditions and some limited reforms that have been introduced to redress them, particularly in England, Australia, Canada, and public international tribunals. The section concludes with some observations about the limits of legal transplants and analyses why some proposed reforms have not taken hold.

1. National differences in expert witnessing

4.09  In common law jurisdictions, most notably the United States, experts are selected and paid by the parties. In fact, these witnesses are often described not simply as a ‘party-appointed expert’ or ‘party-selected expert’14 but as a ‘party’s expert’, with the possessive pronoun (p. 142) linguistically signalling that a party somehow owns the expert, or at least his or her testimony. In some non-trivial way, it is accurate to speak of an ‘ownership’ interest. Expert witnesses are carefully selected based on how well their perspectives, opinions, and (ultimately) conclusions fit with parties’ overall case strategy. Unlike other fact witnesses, ethical rules generally permit attorneys to compensate expert witnesses for their time. Some systems even permit experts to be compensated on a contingency fee basis.15 While most jurisdictions prohibit such forms of compensation,16 experts are generally allowed to work closely with counsel and remain intimately involved in case preparation.

4.10  One US commentator offers this explanation of the practical mechanics of experts’ relationships with attorneys:

Litigation is a complex process, and it is important that attorneys be able to communicate with the experts working on the case. The lawyers will invariably have important information, and perhaps suggestions, that will facilitate the experts’ work. Lawyers may also need constant input from the experts as the case proceeds, so that they may adjust their goals and strategies in light of the experts’ findings.17

Particularly in complex cases, expert testimony is regarded as so essential to parties’ ability to prepare and present their cases that it is treated as an essential procedural right.18

(p. 143) 4.11  In the US legal system, expert testimony is consistently used in many, if not most, cases, from basic tort cases to employment discrimination cases to complex commercial cases.19 In criminal20 and mass toxic tort cases—arguably the genres that define the most distinctive qualities of the US legal system—expert testimony plays an especially pivotal role in establishing liability and developing innovative new legal theories.21 It would be difficult to overstate the importance of expert testimony in US litigation and to US parties and counsel in developing their case strategy.

4.12  Despite this need for close coordination, however, commentators argue that expert coordination with counsel is ethically legitimate only ‘so long as the relationship remains independent and professional roles are not blurred’.22 The meaning of the term ‘independent’ in this context is by no means self-evident. The term ‘independent’ to describe the obligations of an expert who is unilaterally selected and compensated by only one party, and who works extensively with that party’s counsel, cannot have the same meaning as the requirement that an arbitrator remain ‘independent’ of the parties and their counsel. It also necessarily means something different from the ‘independent’ judgment that attorneys are required to exercise under national ethical rules.23

4.13  While commentators opine about where the line exists between experts’ professional independence and permissible coordination with lawyers, lawyers in practice publicly and expressly doubt such a line exists. As John C. Shephard, the former president of the American Bar Association explained, ‘I would go into a lawsuit with an objective, (p. 144) uncommitted, independent expert about as willingly as I would occupy a foxhole with a couple of noncombatant soldiers’.24 The academic use of the term ‘independent’ to describe expert witnesses, in other words, contrasts sharply with established practices in the US system.

4.14  While US attorneys are not sure where the line is between assertions of independence and actual practice, in most civil law systems, the entire idea of drawing such a line is an anathema. In systems such as Germany, France, Italy, Turkey, and the Netherlands, experts are most often appointed by the court.25 For instance, in France, Italy, and Hong Kong, the court has exclusive power to appoint experts, usually selected from an approved list and upon party application. Germany, meanwhile, uses a dual system of court-appointed and party-selected experts, but judges are still required to adopt an expert agreed to by the parties or to select an expert from a prescribed list.26

4.15  Experts in civil law jurisdictions are usually obliged, under applicable procedural rules, to be neutral and impartial.27 With court-appointed experts in civil law systems, parties can seek to recuse any expert who is not ‘neutral’, and that standard is interpreted as being as rigorous as related judicial obligations.28 In fact, in Germany, the standards for expert and judicial neutrality derive from the same provisions from the German Code of Civil Procedure.29 Under these regimes, it is simply not permissible for counsel to meet with and coordinate their cases with expert witnesses.

4.16  There are some notable exceptions in which the independence obligations of both judges and experts are less clear. For example, in Brazil, there can be three (or more) expert witnesses, one appointed by the judge and two party-selected experts. Under Brazilian procedures, a judge can communicate with the parties ex parte at any time to ask them questions and can appoint an expert witness, if necessary, to act either separately or in coordination with expert witnesses selected by each of the parties.30

(p. 145) 2. Criticisms and exceptions

4.17  Even if national traditions regarding expert witnesses are firmly entrenched within particular legal systems, the prevailing common law and civil law traditions are subject to significant criticisms from both inside and outside their home systems. These criticisms have given rise to proposed reforms and important exceptions to the prevailing approaches in both common law and civil law systems. As described in more detail later, some reforms have been successful, but many other reforms have not. This section explores what factors contribute to the success or failure of particular reforms. Building on these observations, Section C of this chapter identifies specific reforms for expert witnesses in international arbitration that it is later proposed in Chapter 6 be adopted as part of a larger project of self-regulation.

a. The United States

4.18  As already described in Chapter 3, the US legal system is probably the most permissive in terms of the nature and extent of contact permitted between lawyers and experts. As a consequence, it is often regarded as the most tolerant of expert witnesses who have partisan dispositions. The criticisms of this tolerance are legion. On the one hand, critics argue that these expert witnesses fail to clarify the issues to be adjudicated because their testimony is tailored to further the client’s case strategy, rather than to provide a full analysis of a given issue.31 Relatedly, critics argue that excessively adversarial experts tend to polarize the case, potentially creating conflict and even confusion when in actuality little conflict exists.32

4.19  Both of these critiques illustrate the basis for yet a third critique—that exaggeration by partisan experts distorts an adjudicator’s decision-making, which in turn creates incentives for experts to exaggerate further. For example, if a respondent’s expert values lost profits at US$5 million and the claimant’s expert at US$10 million, a tribunal might reasonably believe that the true value is around US$7.5 million. The inclination toward splitting the difference between expert conclusions is relatively natural, but it invites potentially exaggerated and unethical contentions from experts.

4.20  For example, if the claimant’s expert opines that the value of lost profits is US$100 million instead of a more reasonable estimate of US$10 million, it would transform the average from US$7.5 million into US$52.5 million. In this respect, compromise outcomes can penalize honest expert estimates and reward improperly exaggerated testimony. A compromise decision is especially problematic when the true value is either very high or very low, for example, in cases when the proper outcome is that there is no liability. This propensity for decision-makers to gravitate toward an average between numbers presented by experts has been documented by empirical and social scientific research into US jury decision-making.33 It has also been documented among judges and, by extension, arbitrators.34

(p. 146) 4.21  Some reforms have been proposed to resolve these perceived excesses. Most notably, Federal Rule of Evidence 706 was developed to allow for courts to appoint experts.35 The primary purpose of Rule 706 is not to displace party-selected experts, but instead to supplement them. As one commentator explains, the purpose of a court-appointed expert is ‘to enhance the information available to the trier of fact’ and ‘fill in gaps of knowledge necessary for resolution of the parties’ dispute’.36

4.22  Despite this limited role, and urging by several commentators,37 US judges are reticent to use Rule 706 to appoint their own experts.38 Even precautionary measures imposed by the Rule have apparently not been sufficient to overcome judicial concerns.39 Empirical research shows that this reluctance40 is a result of ‘uneasiness with court-appointed experts [because of] difficulty in accommodating such experts in a court system that values, and generally anticipates, adversarial presentation of evidence’.41 Leading scholars advocating for court-appointed experts even concede that this judicial reluctance is ‘understandable’ since judges are products of an adversarial tradition that is deeply ‘ingrained’.42

4.23  Another, even more recent, effort highlights another difficulty in enacting effective reforms. In 2011, the Litigation Section of the American Bar Association (ABA) sought to promulgate Standards of Conduct for Experts Retained by Lawyers (Standards). Although the Litigation Section announced in August 2011 that the Standards had been adopted by the (p. 147) ABA,43 the Standards were abruptly withdrawn to be further revised.44 The Standards were revised two more times before being unofficially tabled in August 2012.45 A brief look at the adopted-then-retracted Standards reveals both the substantive complexities and the politics in regulating expert witnesses.

4.24  As an initial matter, there are serious doubts about whether the ABA even has the authority to impose standards on experts who act as witnesses. The ABA is a professional organization with indirect authority over the members of one profession—lawyers46—but no authority (direct or indirect) over other professions. In an apparent attempt to resolve this jurisdictional problem, the Standards were framed as providing guidance to experts who are ‘retained by lawyers’. Specifically, they stated an aspiration that lawyers incorporate the Standards into their letters retaining experts, so that ‘experts and clients will have a common understanding of what is expected’.47 Most objections to expert testimony, however, are not tied to misunderstandings about what is expected. The objections, instead, are that expert witnesses implicitly or explicitly collude to have experts bend their testimony to suit client and attorney expectations.

4.25  Even more importantly, this attempted jurisdictional side-step was itself a profound misstep—technically clients retain experts, not lawyers.48 These are only a few of the most obvious problems with the now-withdrawn proposed Standards. In light of these problems, repeated revisions, and defeat of the Standards, it is fair to assume that any renewed effort to promulgate standards will be facing some serious challenges.

b. England, Australia, and Canada

4.26  The procedural traditions of England, Australia, and Canada are often characterized as generally less starkly adversarial than the United States. In keeping with these characterizations, these jurisdictions place more restrictions on attorneys in their interactions with witnesses generally, and with expert witnesses in particular. As noted in Chapter 2, the common practice of ‘preparing’ a witness —particularly rehearsing questions and answers—would be considered unethical in Australia and England, and illegal in Canada.49 Despite restraints on (p. 148) advocates, many of the same concerns raised about US procedures regarding expert witnesses have also been raised in these jurisdictions.

4.27  In response to these concerns, Lord Woolf undertook to evaluate expert witness practice in England and Wales. His assessment could easily also describe concerns about the US system:

Expert witnesses used to be genuinely independent experts. Men of outstanding eminence in their field. Today they are in practice hired guns: there is a new breed of litigation hangers on, whose main expertise is to craft reports which will conceal anything that might be to the disadvantage of their clients.50

These comments predicated the so-called ‘Woolf Report’, which in turn led to the extensive reforms in the procedural rules of England and Wales. The overall purpose of the reforms regarding expert witnesses was to compel experts to function in the service of the judge, and not simply in the interests of the party that retained the expert. To that end, the reforms included many rules that provide guidance to experts on how to fulfil this new mandate.51 Not all assessments of the Woolf reforms are uniformly laudatory. Most practising barristers report, however, that there has been a significant shift in practices and decorum involving experts in English courts since the reforms were implemented.52 In light of their success, the Woolf Reforms have inspired similar, and in some instances even more far-reaching, reforms in Australia,53 Canada, Hong Kong, Singapore, and New South Wales.54 Canada’s reforms are particularly interesting. Following Australia’s lead, in 2010 the Federal Court in Canada similarly introduced a Code of Conduct as a schedule to the Federal Rules of Court. The Code requires counsel to provide expert witnesses with the Code of Conduct when they are initially retained and further requires that expert witnesses sign a certificate acknowledging that they agree to be bound by the Code.55

4.28  Another innovation introduced in Australia, and more recently in England, is expert witness ‘hot-tubbing’ (also referred to as ‘concurrent evidence’, ‘joint meeting’, ‘expert conferencing’, (p. 149) and ‘witness conferencing’).56 The essence of hot-tubbing is that the experts present their findings to the court virtually simultaneously. After being sworn in together, the experts in turn summarize key findings and ask questions of and respond to the opposing expert. Subsequently, counsel and the court may or may not cross-examine and question the experts, who may, in turn, again have opportunities to elaborate.57 Although criticized by some,58 hot-tubbing has also been commended as an effective technique to save time and hone in on key areas of dispute.59

4.29  Joint conferencing is another procedural innovation that has been used with success in Australian courts60 and is now recognized under Australian federal rules and New South Wales.61 Similar to hot-tubbing, joint conferencing also allows discourse between two or more experts. The difference is that in joint conferencing, the experts meet outside of court and off the record. The experts then produce a document outlining areas of agreement and disagreement discussed during the joint conference.62 Joint conferencing is used in international arbitration,63 but is also still subject to scepticism about its adequacy for exceptionally complex scientific issues that involve mixed questions of law and fact.64

(p. 150) 4.30  As discussed in greater detail later, these reforms curbed some of the most extreme excesses in those jurisdictions that have adopted them. The function of experts, however, remains largely the same (i.e., they are selected, compensated, and prepared by parties and their counsel). It remains exceedingly rare for judges to appoint expert witnesses directly, and the procedural reforms described earlier have not completely dispelled that reluctance.65 As a result, there remain questions about the true value of the reforms,66 as well as more precise questions about which aspects of the reforms have effectuated the most significant changes.

c. Germany, Italy, and the Netherlands

4.31  In civil law systems, such as Germany and the Netherlands, conventional procedures for court-appointed experts have also been subject to criticism, and some exceptions have developed to redress concerns. The advantage of tribunal-appointed experts is that they avoid many of the biases introduced by an adversarial process in which experts are selected and paid by parties and work intimately with parties’ legal advocates in the development of case strategy. While this is an obvious advantage, more recent criticism takes aim at the extent to which court-appointed experts are, or can be considered to be, completely unbiased. The notion of objectivity or neutrality in an expert witness, it is argued, is based on an unduly restrictive definition of bias.

4.32  While the cognitive biases of expert witnesses have not been studied as extensively as those of judges (and, by extension, arbitrators) they are an unsurprising by-product of the fact that experts, like judges and arbitrators, are human.67 Despite training and even scientific understanding of cognitive biases, experts are not themselves insulated from cognitive biases that affect all humans. Some of these biases are particularly prevalent, and uniquely troubling, in legal decision-making. One is the so-called anchoring bias, in which individuals facing a complex decision rely on initial reference values that may be incomplete or irrelevant in making their final assessment. For instance, litigators may hypothesize a low damage estimate to an expert in an initial meeting that then becomes the basis for a cognitive anchor in later ostensibly independent analysis.68 This form of cognitive bias, and the erroneous analysis it (p. 151) can produce, is difficult to dispel, even when the expert knows that anchoring information is from a source that has low credibility.69 While this potential for innocent or unknowing expert witness bias raises some concerns about the information parties’ and their counsel provide to expert witnesses, it and other known cognitive biases also raise fundamental questions about the possibility for any expert, including a court-appointed expert, to be truly ‘unbiased’.

4.33  While presumably free of pressure from parties, tribunal-appointed experts may be subject to various types of cognitive and heuristic biases that are introduced by their own background and training, personal beliefs, or ‘prevailing culture’.70 As Stephen Jay Gould, famed evolutionary biologist and popular science writer, explained:

Facts are not pure and unsullied bits of information; culture… influences what we see and how we see it. Theories, moreover, are not inexorable inductions from facts. The most creative theories are often imaginative visions imposed upon facts; the source of imagination is also strongly cultural.71

Gould is expressing here the same sentiment as Marcus Aurelius at the beginning of the chapter. Objective perception of facts and assessments of truth are subject to the limitations of sensory perception and the cognitive biases that affect how humans, including experts, process information.

4.34  In the adjudication context, an expert opinion is an assertion of expert knowledge regarding an interpretation of, or prediction about, an often complex amalgam of observable facts.72 It is not usually, in itself, an objective fact or an individual’s recollection of an objective fact.73 Applying Gould’s observation to expert witnesses, in processing data to make an expert interpretation or prediction, the expert witness necessarily refracts the data through his or her experience and predispositions. This refraction is not so much an aberration, but in fact part of why experts with particular backgrounds or forms of expertise are selected, by either parties or tribunals.

4.35  Reliance on a single, tribunal-appointed expert obscures this reality. Instead, when a tribunal appoints a ‘neutral’ court-appointed expert, the process itself implies that there is only one right answer to the complex issues that are the subject of expert testimony.74 In (p. 152) some instances, the tribunal’s selection of an expert from one school of thought (as opposed to another) can be outcome determinative.75 Meanwhile, reliance on tribunal-appointed experts may also discourage introduction of novel legal theories that might be sustained by expert testimony.76

4.36  Bias in cognition of so-called neutral experts may seem less pernicious than biases that result from adversarial attempts to co-opt expert opinions. They can, however, be even more problematic precisely because they are more likely to escape detection or challenge.77 As a practical matter, it can be exceptionally difficult for parties to challenge a court-appointed expert’s opinion, particularly since expert analysis may be needed to identify the source of certain errors.78 Even if an important error were found by a party-retained expert, the perceived neutrality of tribunal-appointed experts may cause adjudicatory decisionmakers (judges, juries, or arbitrators) to treat their testimony as unassailable.79 In other words, the perception of impartiality may create an undeserved ‘aura of infallibility’ for tribunal-appointed experts.80 As one scholar notes, ‘All error is problematic, but unrebutted error is especially so.’81

4.37  In an effort to redress this problem, most procedural rules in national legal systems and in international arbitration preclude adjudicators from treating expert opinion as decisive on an issue.82 These rules legally require tribunals to make an independent determination of (p. 153) the issue on which expert testimony is offered. The impulse to defer, however, is strong, particularly when there is only one source of expert testimony and the issue is extraordinarily complex. The most ardent critics argue that the impulse to defer is more operative than expected or desirable.83

4.38  Another potential protection against these concerns about court-appointed experts is that civil law systems increasingly permit parties to retain their own experts.84 As a practical matter, however, parties rarely do. There are several reasons for this reluctance. First, experts can usually be appointed by a party only if the court grants the party permission. When such experts are permitted, their opinion does not generally have the same value as that of a court expert.85 Instead, in civil law systems, an opinion by a party-selected expert is generally treated as an assertion of a party, not as evidence.86 As a consequence, the party submits the expert’s report to the court, but the party-selected expert is not examined at trial.87 The utility of party-selected experts is thus generally limited in civil law systems, making it difficult to justify any benefit as weighed against the cost of retaining an outside expert. Just as courts are reluctant in the United States to appoint experts to counterbalance excessive partisanship of party-selected experts, parties in civil law systems are sceptical about the value of party-selected experts to counterbalance concerns about court-appointed experts.

d. Expert mechanisms in public international tribunals

4.39  To understand the ethics of expert witnesses in international arbitration it is also useful to look at existing practices in public international courts. Like international arbitration, these tribunals also adjudicate disputes among parties from various cultural and legal traditions, and consequently share many of the same challenges faced by international arbitral (p. 154) tribunals.88 A major difference is that public international tribunals are tethered to State- and treaty-based rules and may be less flexible than international arbitral tribunals that are the product of private party agreement.89 Nonetheless, with increasing reliance on expert witnesses to opine on scientific and technical matters, public international courts have etched a growing record of procedural innovation in assimilating expert evidence.

4.40  Both public international tribunals90 and parties in proceedings before those tribunals are generally presumed to have powers to appoint experts. In contrast to national jurisdictions, public international adjudications often use a combination of both party-selected and tribunal-appointed experts simultaneously, and like recent reforms, have them operate in dialogue with each other.91 Another procedural innovation for seeking expertise, which arguably avoids at least some of the concerns with existing national practices, is for tribunals to seek out independent outside international organizations for expert advice. For example, the International Court of Justice (ICJ) rules specifically provide for opinion requests from public international organizations such as the World Health Organization (WHO).92 World Trade Organization (WTO) panels have similarly sought expert advice for international organizations.93 The use of such organizations in place of experts can raise unique concerns (p. 155) about independence since, like individual experts, organizations often have their own policy objectives that can affect their assessment of particular issues.94

4.41  Another, less salutary development is that some international courts have diluted or dissolved altogether the delineation between advocates, arbitrators, and experts. In the ICJ context, expert witnesses have appeared in court in the role of full advocates or counsel.95 In the Gabcıkovo-Nagymaros case,96 for example, Hungary had its four scientists appear as ‘advocates’ while Slovakia had its two scientists appear as ‘counsel and experts’. Counsel for Hungary made a point of clarifying that Slovakia’s scientists, like Hungary’s scientists, appeared as advocates.97 Similarly, in the Case concerning Pulp Mills,98 both parties included six delegation members as ‘scientific advisors and experts’. Correspondence between the parties clarified that these representatives were speaking in the capacity of advocates rather than expert witnesses.99 The perceived advantage of experts-as-advocates is that it arguably eliminates concerns about expert biases and shifts the enquiry from questionable assumptions about independence to more direct questions about persuasiveness on the substance of the issue. Such blurring of roles, however, requires considerable procedural jerry-rigging concerning how to handle examination and cross-examination of experts, whether or not to require standard expert oaths,100 confusion of mixed issues of fact and law, and misconstruction of professional ethical obligations.101 In fact, experts-as-advocates created such difficulty in Pulp Mills that in a separate opinion one judge specifically criticized the practice and underlined the Court’s ‘unequivocal indication’ that ‘the practice should not be repeated in future cases’.102

4.42  Another practice that occurs among public international tribunals is the allowance of direct appointment of experts to the tribunal,103 either by appointing experts directly as voting or non-voting members of the panel, or conscripting technical assessors to advise the panel.104 For example, both the ICJ and tribunals formed under the UN Convention on the Law of the Sea (UNCLOS) retain power to appoint non-voting experts to the tribunal.105 The perceived (p. 156) advantage of this approach is to ensure the panel’s ability to identify, understand, and address technical issues in a more efficient manner than formal admission of expert evidence.106 This blurring of roles, this time with experts-as-adjudicators, raises similar and even more significant concerns, however, about these experts’ potentially excessive (and non-transparent) influence on the tribunal.107 Expert input directly to the tribunal bypasses evidentiary processes and precludes any opportunity for parties to comment, challenge, or refute.108 Perhaps due to these concerns, arbitrators appointed based solely on scientific or technical qualifications are relatively rare, and primarily used under narrow jurisdictional guidelines for highly technical matters.

4.43  Where experts are required on a tribunal, courts generally maintain a permanent roster of technical experts in order to facilitate selection by the parties.109 For instance, experts chosen for special arbitral tribunals under Annex VIII of UNCLOS are selected from lists of experts in a range of environmental and maritime fields; individuals on those lists are nominated by Member States and the lists themselves are maintained by subsidiary bodies or public international organizations.110 Drawing experts from permanent, formally maintained lists is a practice that is also used in certain civil law jurisdictions.111 Commentators have urged expanding the practice in the international public law context—notwithstanding the potential impracticalities of maintaining up-to-date lists of experts in a wide range of fields and subject matters.112

4.44  Another expert procedure worth adding to this survey is the unique WTO two-phase procedure for assimilating expert evidence.113 In the first phase, the tribunal submits a list of written questions to the experts based on party requests submitted to the tribunal. After the experts provide written responses, parties may comment on both the expert responses and the comments of other parties, which are then circulated to all parties and experts. The tribunal then drafts a report on the preliminary questions, seeking confirmation of the report’s accuracy from the experts where necessary. The second phase consists of ‘joint meetings’, whereby the parties, experts, and arbitrators meet together to clarify the issues. First, the experts introduce and discuss the issues and party comments. The parties submit follow-up questions, which are relayed by the tribunal to the experts, who provide on-the-spot answers. (p. 157) The arbitrators may then ask for clarification of certain points, after which the experts provide closing statements. Finally, experts may comment on the transcript of the joint meetings before it is entered into the record.

4.45  Joint meetings share much in common with hot-tubbing, outlined in Section A.2.b. The major difference with the WTO practice is that the tribunal acts as an intermediary between experts and parties, which eliminates cross-examination and separate pleading. Proponents of the WTO approach argue that it promotes clarity on technical issues and enough flexibility to accommodate all parties.114 Critics, meanwhile, complain that it has an off-the-cuff nature that reduces predictability, and that time constraints on oral meetings may lead to incomplete answers and back-of-the-envelope data guesstimates instead of needed precision.115

4.46  Many of the innovations that exist in international tribunals are either not feasible or perhaps not particularly desirable in international arbitration. They demonstrate, however, that the role of expert witnesses is not limited to the formulations developed in national legal systems. With this background of expert witnesses in national legal systems and before public international tribunals, the next part turns to the ethics of experts in international arbitration.

B. Expert witnesses in international arbitration

4.47  The inability of the national procedural reforms to resolve perceived problems in national legal systems is, at least in part, symptomatic of legal transplants more generally. A ‘legal transplant’ is a ‘doctrine or legal rule that is transposed from one legal system into another’.116 The reforms described in earlier sections seek to permit court-appointed experts in common law systems and party-selected experts in civil law systems. Unfortunately, these ‘legal transplants’, like their botanical counterparts, are not always adaptable to a new climate. There is extensive scholarly analysis of the reasons why some legal transplants ‘take root’ and others are rejected as incompatible with the host state’s ‘procedural ecology’.117 In the case of expert (p. 158) witnesses, the procedural innovations did not mesh well with culturally entrenched,118 longstanding, and familiar processes.119 Instead, they ‘pushe[d] against the deeply ingrained norms, roles, and incentive structures’ in the respective systems.120

4.48  In contrast to largely unsuccessful legal transplants at the national level, international arbitration provides exceptionally fertile ground for procedural innovations.121 The ‘norms, roles, and incentive structures’ that inhibit reform at a national level are not firmly entrenched in international arbitration procedures. Quite the opposite; international arbitral procedures were developed to accommodate parties, arbitrators, and counsel from different legal cultures. The prevailing procedures in international arbitration are those that have proven popular and effective to parties, counsel, and arbitrators from many jurisdictions working together. As a result, they usually represent procedural hybridizations based on an amalgam of national procedural traditions that have had their mettle tested in international arbitral proceedings.122

4.49  The prevailing international arbitral procedures have been distilled down and codified in the International Bar Association (IBA) Evidence Rules.123 While this codification provides (p. 159) a degree of continuity and shared understanding, unlike national rules, the IBA Evidence Rules are not founded on as culturally entrenched norms as are rules in national legal systems. Efforts to reform the IBA Evidence Rules are subject to the same political wrangling that occurs with any negotiated compromise in cross-cultural settings. There are, however, much lower hurdles at the international level than the potentially insurmountable political obstacles that must be overcome to ratify reforms within national legal systems.

4.50  In international arbitration, reforms are adopted at the retail level. Proposed reforms are not imposed as top-down pronouncements, but as flexible options that are distilled out of prevailing practices and can be adopted in particular cases. Unpopular reforms are simply ignored or rejected. As discussed later in this chapter, this measure of freedom affords international arbitration an opportunity to redefine the role, and correspondingly define the ethical obligations, of the expert witness in a manner that is simply not as feasible in national legal systems.

4.51  Since States do not generally regulate the ethics of experts appearing in their own national court proceedings, it is not surprising that national arbitration laws generally ignore the ethics of experts in arbitral proceedings. Both institutional and ad hoc international arbitral rules are similarly elliptical about the conduct and ethical obligations of expert witnesses.124 Recently, the topic of expert ethics has garnered interest from commentators,125 but the direction of future reforms is not yet certain. The establishment of ethical standards for experts raises some unique challenges and opportunities for international arbitration.

4.52  One additional challenge in regulating expert witnesses in international arbitration is that, unlike domestic legal systems, there is no single predominant model for how expert witnesses are appointed and function. International arbitration permits a range of possible models for expert witnesses. While this flexibility creates some challenges, it also affords unique opportunities for new regulation at the international level and within international arbitral procedures. To the extent that the most promising reforms seek to re-acculturate participants and restructure the role of experts, such reforms may be more feasible in international arbitration than they are in domestic systems, where the role of experts is more culturally entrenched.(p. 160)

4.53  In the remainder of this chapter, Subsection 1 explores procedural innovations, often inspired by some of the national reforms described in the previous part. The prevailing standards and practices in international arbitration focus on efforts to improve them. Subsection 2 considers a few deviations from standard practice that cause problems, and finally Section C assesses certain reforms that have recently been introduced in international arbitration.

1. Expert witness traditions and innovations

4.54  One hallmark of international arbitration’s procedural flexibility is that it aims to accommodate party preferences. As a result, the nature of and procedures for introducing expert witness evidence often depend on party preferences. These preferences are usually determined by express agreement or indirectly as determined by the predilections of arbitral tribunals selected by the parties. Tribunals comprised of arbitrators from common law jurisdictions will ordinarily permit the parties to present party-selected expert witnesses through procedures consistent with the traditions in common law systems.126 In contrast, parties or tribunals dominated by specialists from civil law backgrounds ‘may be more skeptical about the benefits and costs of party-nominated expert witnesses’.127 It still happens that civil law dominated arbitral tribunals, ‘particularly more traditionally-minded ones’,128 may permit only tribunal-appointed experts.

4.55  New rules are increasing flexibility and making expert witness options more expressly subject to individual party preference, even absent mutual party agreement. For example, the IBA Evidence Rules provide that ‘A Party may rely on a Party-Appointed Expert as a means of evidence on specific issues’129 and that in response to a Report from a tribunal-appointed expert, ‘any party shall have the opportunity to respond to the Expert Report’ by various means including through ‘an Expert Report by a Party-Appointed Expert’.130 These provisions seem to create rights for parties to use party-selected experts that are not conditioned either on tribunal permission or agreement from an opposing party.

4.56  More generally, the IBA Evidence Rules provide a number of innovative options including preliminary party-selected expert conferences, rights to cross-examine, access materials relied upon by tribunal-appointed experts, and even hot-tubbing.131 These rules can be mixed and matched in whole or in part.132 While historically arbitral rules were more predisposed towards either common law or civil law approaches,133 institutions are increasingly hybridizing and addressing in more detail the manner expert evidence is assimilated. For example, (p. 161) the Chartered Institute of Arbitrators (CIArb) provides online practice guidelines covering procedures and strategies for using party-selected and tribunal-appointed experts.134 The China International Economic and Trade Arbitration Commission (CIETAC) also recently expanded its arbitration rules to allow for oral expert evidence,135 and the International Chamber of Commerce (ICC) includes a special International Chamber for Expertise that can be consulted to recommend or appoint experts or even administer expert proceedings under its rules.136

4.57  In addition to procedures that have been distilled into formal rules and protocols, other innovations are also being experimented with on an ad hoc basis. For example, ‘expert teaming’ (also known as ‘Sachs protocol’) is regarded as an innovation that finds middle ground between party-selected and tribunal-appointed expert traditions.137 In expert teaming, the tribunal first invites parties to each provide a short list of potential expert candidates. Then, the tribunal chooses one expert from each list jointly as an ‘expert team’.138 Afterward, parties and the tribunal may choose other procedures for presenting expert evidence and examining the experts, such as cross-examination, expert conferencing, and the like.

4.58  In the alternative, parties and tribunals may craft something similar to the two-phase procedure used in the WTO (discussed earlier). In fact, this system that has arisen as ‘the de facto standard procedure in the WTO’ itself sprouted organically from nebulous procedural guidelines and the unique conditions of WTO proceedings.139 Witness conferencing is already apparently on the rise.140 Other expert witness procedures may also evolve in international arbitration given its similarly flexible procedures and continued efforts to find efficiencies.

(p. 162) 2. Efforts to clarify standards for expert ethics

4.59  Like rising consciousness about the costs associated with ambiguity about counsel ethics, there is an increased recognition that the absence of regulation regarding expert ethics may increase the costs and reduce the accuracy and efficiency of arbitral proceedings. As a result, calls for and efforts at reform have increased.

4.60  Although ostensibly evidentiary rules, not ethical rules, the IBA Evidence Rules have attempted to take on this challenge. The drafters of the IBA Evidence Rules expended significant effort on expert witnesses, dedicating separate articles to party-appointed experts (Article 5) and tribunal-appointed experts (Article 6). These new articles contribute some measured progress in delineating the distinction between party-selected and tribunal-appointed experts. Ultimately, however, the Rules may do more to highlight problems than to resolve them. They also make assumptions and impose obligations that will likely have to be reconsidered in subsequent revisions to the Rules.141

a. Disclosure obligations under the IBA evidence rules

4.61  The first point of concern involves the unequal, and arguably inverted, disclosure obligations imposed on different types of experts. Under Article 5 of the IBA Rules of Evidence, party-selected experts are specifically required to state their ‘present and past relationship (if any) with any of the Parties, their legal advisors and the Arbitral Tribunal’.142 Curiously, there is no similar disclosure obligation imposed on tribunal-appointed experts. This omission is surprising because the Rules confer on tribunal-appointed experts powers that are analogous to, and even commensurate with, those of the tribunal. For example, the tribunal-appointed expert has the power to request and access information, and the expert’s authority to do so is described as ‘the same as the authority of the Arbitral Tribunal’.143 How can an expert have powers similar to the tribunal but not be subject to disclosure qualifications to ensure that those powers are exercised in a fair and equitable manner?

4.62  While disclosure obligations are limited to party-selected experts, both party-selected and tribunal-appointed experts are required to submit a statement of their ‘independence from the Parties, their legal advisors and the Arbitral Tribunal’.144 This statement of independence seems reasonable as a requirement for tribunal-appointed experts, but further emphasizes the oddity of not requiring separate disclosure. A tribunal-appointed expert may have some ‘present or past relationship’ that would be disclosable under the standard announced in Article 5.2(a) for party-selected experts, and presumably should be disclosed. That same information may not be sufficient to preclude a tribunal-appointed expert from acting independently and therefore may not be deemed sufficient to interfere with submission of the (p. 163) requisite statement of independence.145 For example, what if a tribunal-appointed expert were testifying in other cases before members of the same arbitral tribunal on similar issues? Or if the tribunal-appointed expert had been appointed several times in the past year by one of the parties’ law firms? Why should such information be required to be disclosed by a party-selected expert, but not a tribunal-appointed expert? To the extent that party-selected experts’ disclosure obligations are important to reveal a suspected intellectual tilt, why is the same information deemed irrelevant for those experts who are presumed to have no tilt?

4.63  This incongruence is especially peculiar given that disclosure of information by a party-selected expert is arguably less critical. For party-selected experts, other protections exist to test their credibility, such as cross-examination and the substantive testimony of an opposing party-selected expert.

4.64  Apart from the IBA Evidence Rules, disclosure of conflicts of interest is a potential reform that has been suggested to clarify expert witness’ independence and potential influences.146 Experts should be and generally are required to disclose their level of compensation and the number of repeat engagements for a particular party, law firm, or professional perspective. Some industry regulations also require disclosure of conflicts of interest. Consistent with the general focus of industry-based regulations, those requirements are usually aimed at the conduct of experts in their primary professional occupation, not when they are ‘moonlighting’ as expert witnesses.147 Moreover, overly rigorous expert disclosure of potential conflicts of interest may not be a cure-all and can potentially be counterproductive. In one study, experts required to disclose conflicts of interest were less accurate in their expert advice, ‘perhaps because the disclosure made experts feel some sense of “moral license”’.148 Even if not a panacea, disclosure of potential conflicts is an important means of increasing transparency, which may in turn press parties to be more careful in selecting experts who are free from obvious and discrediting conflicts.

b. Obligation of independence

4.65  The IBA Evidence Rules also impose what purports to be a uniform duty of ‘independence’ on both party-selected and tribunal-appointed experts.149 In this respect, the IBA Evidence Rules are not unique. For example, the Protocol for the Use of Party-Appointed Expert Witnesses in International Arbitration developed by the Chartered Institute of Arbitrators provides that: ‘An expert’s opinion shall be impartial, objective, unbiased and uninfluenced by the pressures of the dispute resolution process or by any party.’150 Similarly, the IBA Rules purport to apply the same obligation of ‘independence’ to both party-selected and tribunal-appointed experts.

(p. 164) 4.66  The phrase ‘independent party-selected arbitrator’ sounds more like an oxymoron than a reasonable aspiration. Almost definitionally, a party-selected expert is not ‘independent’ of the selecting party, at least not in the same way that a tribunal-appointed expert is expected to be ‘independent’. Party-selected experts are compensated by the one party. They receive instructions from and engage in extended communications with the counsel for that party. They testify or submit reports ‘on behalf of’ or ‘in support of’ that party’s case and they are cross-examined only by the opposing party. In light of these factors, a party-selected expert cannot be considered ‘independent’ in the same sense that the term is generally used with respect to tribunal-appointed experts, or other professionals to whom the same term is applied.

4.67  Even if the IBA Evidence Rules ascribe an inconsistent and muddled meaning to the term ‘independent’, in some respects, the drafters were only replicating a problem that already exists in other contexts. First, there is an apparent analogy between party-appointed arbitrators and party-selected experts. Under most arbitral rules, all members of an arbitral tribunal, including party-appointed arbitrators, must sign a statement or otherwise attest to their independence from the parties.151 Many sources that regulate arbitrator conduct also underscore that party-appointed arbitrators are bound by the same ethical standards—including a duty of independence—as arbitral chairpersons. As examined in greater detail later in Chapter 8, however, key differences exist between party-appointed arbitrators and chairpersons that directly affect the nature of their independence obligations.

4.68  Even if there are interesting comparisons between party-selected experts and party-appointed arbitrators, there are also important differences. A party-appointed arbitrator’s obligation of independence generally precludes compensation by only one party (though some rules, such as the American Arbitration Association (AAA) and International Centre for Dispute Resolution (ICDR), permit the practice). Meeting ex parte with only one party is generally regarded as incompatible with an arbitrator’s obligation of independence. Under the historic US practice of highly partisan party-appointed arbitrators,152 some courts reasoned that ex parte communications, non-disclosure of conflicts, and even unilateral compensation were permissible for party-appointed arbitrators.153 In those circumstances, courts reasoned that such conduct was permissible because those highly partisan party-appointed arbitrators were not expected to be independent of the parties.154 As described in Chapter 8, this US practice is (p. 165) now largely discredited and mostly abandoned. US party-appointed arbitrators now generally abide by rules that forbid such on-going ex parte communications and instead require independence.155 The reasoning of these earlier decisions, however, is helpful to understanding why party-selected experts are not ‘independent’. For party-appointed arbitrators, abstaining from ex parte communication is one of the hallmark distinctions between those who are independent and those who are not. Since party-selected experts are selected and compensated by only one party and expected to coordinate and communicate with appointing parties and their counsel, they could not meet this hallmark of ‘independence’, at least not in the same sense that that word is used to describe party-appointed arbitrators.

4.69  To avoid this illogical application, it could be argued that Article 5’s statement of independence for party-selected experts should be interpreted as an expression of the expectation that all experts, regardless of how appointed, will bring to the issues of their expertise ‘independent professional judgment’.156 While the independence or ‘objectivity’ of expert opinions will be discussed in greater detail later in the chapter, the text of Article 5 does not readily lend itself to this interpretation. Article 5 does not use ‘independent’ as a modifier for the party-selected expert’s judgment, testimony, or opinion. Instead, it refers to party-selected experts’ status in relation to the parties who appoint them. In this regard, the term ‘independent’ is used exactly as it is with respect to tribunal-appointed experts in Article 6 of the IBA Evidence Rules, and in the same manner as it is generally applied to members of the arbitral tribunal.157 While it might be hoped, expected, and generally desirable to encourage party-selected experts to exercise independent professional judgment, simply requiring them to state (inaccurately and disingenuously) that they are ‘independent’ of the parties, counsel, and the tribunal does not accomplish that aim. It may even undermine that goal by forcing an illogical recitation that is contrary to their actual status and practice.

4.70  The general statement of independence, as imposed by the new IBA Evidence Rules, may not be a meaningful solution as applied to party-selected experts. There are, however, some procedural innovations that aim at a similar outcome and may have a better chance of ensuring more reliable expert witness testimony.

3. Proposals for expert witness ‘oaths’

4.71  In light of recent reforms in national systems such as England, Canada, and Turkey158 that require experts to swear oaths, some international arbitration commentators have argued that this obligation could be a useful innovation to adopt in international arbitration.159 (p. 166) Despite the apparent appeal, oath-swearing alone (at least as is typically done just prior to testimony) is not likely to provide a meaningful solution. As a threshold matter, some national laws do not permit arbitrators to administer oaths in arbitral proceedings that are seated in those jurisdictions.160 As a result, oath-swearing could not be a universally available reform. At a more fundamental level, expert witness oaths would have certain limitations as compared to fact witness oaths, which may make them less effective.

4.72  Some national judicial systems require experts to take an oath, similar to fact witnesses, to tell ‘the truth’. Since an expert witness’s most critical testimony is often in the form of opinion, however, the basic true-false dichotomy addressed by fact witness oaths are not easily applied, either as a conceptual or a practical matter. An opinion can be unreasonable, unfounded, unsupportable, and unconventional.161 An opinion cannot, however, be ‘false’, at least not in the same way that a statement of fact can be false.162 As discussed in greater detail later,163 it is much more difficult to regulate the unreasonable, unfounded, unsupportable, or unconventional than it is to regulate simple falsehoods.

4.73  Generally, the deterrent effect of an oath lies primarily in the threat of prosecution for perjury. As a legal matter, however, many national laws are relatively tolerant when it comes to potential punishment for witness perjury, particularly in international arbitration.164 Many systems simply do not extend their perjury laws to witnesses in international arbitration.165 Even in those jurisdictions whose law technically extends to witnesses in international arbitrations, national prosecutors have little interest in chasing down errant witnesses who made alleged misstatements in exotic proceedings that are detached from their national legal system. The general reluctance of national prosecutors to pursue criminal investigations for conduct in international arbitrations is probably best demonstrated by the unwillingness of Swiss prosecutors to investigate rather sensational allegations of fraud and misrepresentation in a very highly publicized case in which counsel and parties apparently falsely accused (p. 167) esteemed members of an arbitral tribunal of accepting bribes.166 Prosecutions based on conduct in international arbitrations, however sensational, are exceedingly rare and improbable, even for factual witnesses.167

4.74  Prosecution for allegedly perjurious testimony by an expert witness presents an even greater challenge, even if national prosecutors could be prompted to intervene. First, as already noted, expert witnesses present their most salient testimony as ‘opinion’, not ‘fact’. Second, expert opinions are usually based on complex analysis of a specialized field of study. Indeed, the entire reason to procure an expert is to assist the decisionmaker in resolving a question that is so complex as to require specialized training and experience. Both of these factors make it exceedingly difficult to prosecute expert witnesses for allegedly perjurious testimony.

4.75  Since, epistemologically, expert knowledge is not simply true or false in the same way that factual knowledge is, its accuracy must be broken down into three component parts: belief, truth, and justification.168 As one scholar explains:

Belief is a person’s subjective position concerning the truth of a proposition. Truth is the reality of the proposition independent of belief. Justification involves the quality of the reasons for a belief. To count as knowledge, something must be believed as true, it must be true, and a person’s belief that it is true must be justified. In the absence of a belief, what we have is ignorance. In the absence of truth, what we have is error. In the absence of appropriate justification, what we have is mere opinion.169

In other words, a fact witness testifies regarding the truth of a factual proposition. By contrast, an expert witness testifies regarding his or her belief regarding the truth of an underlying proposition.

4.76  Given the nature of expert witness testimony, it is treated as legitimate, meaning it can be treated as scientific knowledge, if it is justified. A court or arbitral tribunal ultimately must decide for itself the truth of the underlying proposition and, as already noted, many national laws prohibit tribunals from substituting expert opinion for their own legal decisions. An expert is not testifying regarding the truth or falsity of the underlying proposition, but instead only regarding the expert’s belief which is presumably justified by the expert’s knowledge of the field and careful study of the problem. In other words, an expert testifies as to a belief and gives reasons why that belief is justified. The adjudicator must ultimately decide the truth of the proposition.

4.77  Even if the two essential elements of expert testimony—sincere belief and effective justification—are lacking, prosecution for perjury would still be exceedingly difficult.170 On the one hand, an (p. 168) expert can have a belief that is sincere, but false. For example, not only did ‘scientific experts’ in Galileo’s era (today, we would call them ‘church officials’ or ‘religious scholars’) sincerely but inaccurately believe that the sun travelled around the earth, but also that the geocentric theory of celestial bodies was an inalienable epistemological ‘fact’. At Galileo’s trial, if an expert had testified to that sincerely held belief, the expert could not be prosecuted under modern perjury statutes, even though they were completely wrong about the underlying proposition.171

4.78  In modern times, the main critique of expert witnesses is that the beliefs they espouse are insincere, not sincere but mistaken. It would, however, be equally unlikely to have an insincere belief satisfy the modern elements for criminal perjury. Apart from the problems of proving a mental state like insincerity, the modern elements of criminal perjury usually require the defendant 1) be under oath during testimony, 2) make a false statement, 3) make a false statement with knowledge of its falsity, and 4) the false statement must be material to the proceedings.172 Falsity and knowledge of falsity are not standards that fit easily with the nature of expert opinion testimony.

4.79  Another prevailing modern critique of expert witnesses is that even if they sincerely believe in an underlying proposition (or that belief is not easily challenged), that apparent belief is not justified. Such testimony might be reckless and illegitimate. It would be difficult, however, to characterize even reckless testimony as ‘perjurious’, at least in the modern sense of the term. For example, a gambler may have a vehement belief that his lucky number is going to come up on the next spin of the roulette wheel. The gambler may end up being right (and win a lot of money). That outcome, however, would not be the product of ‘knowledge’, despite the gambler’s sincere belief that he ‘just knew’ his number was going to come up.173

4.80  The reason this analogy may seem implausible in comparison to expert testimony is because, even to a layperson, the mechanism of the roulette wheel and the odds of a selected number (p. 169) coming up are both well known. These well-known facts make the probability of the lucky number actually coming up easily verifiable. As a result, the absence of justification seems obvious. With most expert testimony, the absence of justification is more difficult to discern because the underlying proposition is less certain and the methodology used by experts is more opaque to laypersons than the mechanics of a roulette wheel. These circumstances make the absence of justification a difficult predicate for a perjury charge.

4.81  While perjury charges against expert witnesses are almost unheard of, admissibility standards can preclude the introduction of frivolous expert testimony. In most United States jurisdictions, scientific expert testimony is admissible only if it satisfies the so-called Daubert standard, which requires a judge to act as a gatekeeper in determining whether expert testimony proceeds from ‘scientific knowledge’ and is based on sound scientific methodology before they deem it admissible.174 Admissibility standards can play a meaningful role by excluding from evidence expert testimony that is not founded on sound methodology—in other words not justified. These standards generally only exclude questionable categories of expert testimony, however, and do not screen out flimsy opinions issued within a legitimate category of scientific evidence.

C. Procedural reforms and the panda’s thumb

4.82  The Functional Thesis, developed in greater detail in Chapter 7, posits that the procedures in any adjudicatory setting portend the functional inter-relational roles of particular actors, such as expert witnesses. These inter-relational functional roles, in turn, establish a particular range of ethical obligations and limitations that further fulfilment of specific actors’ (in this case, expert witnesses’) role and help identify the factors to be taken into account in making ethical decisions. The Functional Thesis holds two important insights for expert ethics.

4.83  On the one hand, tribunal-appointed and party-selected experts have different inter-relational roles with respect to tribunals, parties, and counsel. The functional role of the tribunal-appointed expert is to assist the tribunal directly and, in this role, to prepare an expert opinion in a manner that is financially and operationally separate from the parties, and may even include tribunal-like powers over the parties. For this reason, the ‘independence’ required of a tribunal-appointed expert precludes the expert from accepting money from only one party or meeting privately with counsel for one party.

4.84  The functional role of the party-selected expert, by contrast, is to develop expert evidence based on information provided by one party and in coordination with party’s counsel. This role also explicitly contemplates that the expert will accept money from and engage in communications with the counsel of only one party, and only be cross-examined by the other party’s counsel. These activities are part of the functional role contemplated for a party-selected expert. Varied roles necessarily mean varied ethical obligations. The role of a party-selected expert is not consistent with the obligation of ‘independence’ that is imposed on the very different role of tribunal-appointed expert witnesses.

4.85  International arbitration employs both types of experts, but separated from the national legal traditions in which they normally operate. This mix-and-match approach means that expert (p. 170) witnesses’ functional roles are not necessarily familiar to all participants. The earlier discussion of the IBA Evidence Rules demonstrated that international arbitration has not clearly delineated the distinct ethical obligations that apply to party-selected experts in contrast to tribunal-appointed experts. These distinctions are all the more important when parties, counsel, and arbitrators do not have shared intuitions and assumptions about what constitutes proper conduct.

4.86  In addition to mixing-and-matching the two archetypes of expert witnesses, international arbitration has also been at the forefront of procedural innovations with respect to expert witnesses, which can further confuse their roles. As described in paras 4.39–4.41, international tribunals also permit development of hybridized inter-relational roles for expert witnesses. As noted, the ICJ has allowed expert witnesses to combine their function with either advocates or tribunal members. Confusion about the nature of these hybridized roles has, in turn, led to confusion about their ethical obligations. Similarly, witness hot-tubbing and witness conferencing can allow tribunals and parties to streamline the otherwise drawn out process of sequential and often contradictory expert testimony. In creating certain efficiencies, these procedures also shapeshift the inter-relational functional roles of expert witnesses by forcing them to interact directly. This new functional role, in turn, potentially raises new issues about their ethical obligations in participating in these processes.

4.87  Donald Elliott has analogized procedural innovations to the panda’s thumb, an evolutionary development that allows an otherwise clumsy paw to efficiently strip shoots off bamboo.175 Similarly, Elliott argues, procedural innovations are often creative evolutionary adaptations that allow new functions that are needed but unaccommodated by a system’s traditional structure.176 Functional roles are sensitive to evolutionary pressures because they are inherently utilitarian. They are driven by pragmatism and often occur on an ad hoc basis. Ethical assumptions and expectations, however, are more constant over time. New roles may portend new ethical obligations, but those new obligations may not be readily accepted as legitimate. Even as the original role to which those obligations were tethered has slipped from its moorings, actors whose role has shifted and those who interact with them in arbitral proceedings may retain background assumptions about what constitutes proper professional conduct.

4.88  This observation about the potential separateness in evolution of inter-relational roles and attendant ethical obligations accounts for some of the confusion that has occurred in particular cases, described later. The resulting confusion cannot be cured with new labels, such as ‘independent’, or quick fixes. They require integrated reassessment of ethical obligations in light of clearly defined inter-relational roles, a topic explored later in Section 1. Even with clear role definition, expert witnesses present unique challenges for effective ethical regulation. As examined in greater detail in Section 2, some of the most effective means of regulating their integrity and professionalism may not be ethical rules at all, but instead checks that structurally corral potential excesses.

(p. 171) 1. Clearer role definition

4.89  Two archetypes for expert witnesses, tribunal-appointed experts and party-selected experts, derive from national legal traditions. Under the Functional Thesis, each archetype can permit a range of legitimate conduct that is tied to the differing legal cultures and the inter-relational roles they impose among parties, counsel, and experts. Within the permissible range of conduct, expert witnesses also inevitably bring their own personal predilections. For example, some party-selected experts might be more accustomed to frequent communications with counsel during the process of writing an opinion, while others may have a personal preference or established practice of more limited communications. Despite room for flexibility within the two archetypes, problems can arise if an expert witness accustomed to operating under one archetypal role is suddenly recast in another. Alternatively problems can arise if their underlying role becomes blurred, particularly as between the two archetypes. In this latter situation, existing ambiguities about the permissible range of conduct for experts becomes even more difficult to discern.

4.90  Existing uncertainties about appropriate ethical obligations for party-selected experts reflect, and even contribute to, confusion about the role of party-selected experts in certain contexts. For example, in the CME-Czech Republic case, allegations were raised that a party-retained expert on Swedish arbitration law crossed an ethical line by acting as de facto co-counsel, actively participating in arguments, instead of as a detached expert.177 Experts on law present unique questions about the role of expert witnesses. National court proceedings rarely permit ‘experts’ on law.178 Instead, judges are generally presumed to be competent in their own legal system and are charged with discerning the law.179 Perhaps as a consequence, there are no well-developed traditions about where to draw the line between advocacy and opining on legal advice. Whatever the line, critics of the expert’s conduct in the CME-Czech case clearly believe participation in oral arguments is outside the appropriate boundaries even if there is no clear guidance on this issue.

4.91  In other examples, the basic role of the expert witness, as either party-appointed or tribunal-appointed, has been scrambled. The result of this scrambling of roles is that the uncertain range of permissible conduct becomes even more uncertain. For example, in the International Centre for Settlement of Investment Disputes (ICSID) award SOABI v Senegal, consistent with German procedures, the tribunal appointed its own expert. It also, however, imported several aspects of US procedures, including some that pertained to the expert witness’s conduct and preparation. For example, the expert was allowed to consider information provided directly by one party, SOABI, without an opportunity for Senegal to challenge its accuracy. On several occasions, the expert was even allowed to meet ‘with SOABI and in the absence (p. 172) of representatives of the Republic of Senegal’.180 Senegal objected to these meetings, but the tribunal rejected these objections, reasoning that Senegal ‘had every opportunity to challenge such information as well as the Report’s conclusions… after receiving its copy from the Tribunal’.181

4.92  Based on the record, it appears that the tribunal permitted the tribunal-appointed expert to engage in extensive ex parte communications with SOABI. While these meetings would be perfectly normal if the expert were appointed by SOABI, it is highly unusual given that the expert was appointed by the tribunal. The problem is not that the expert’s role was converted to be more akin to that of a party-selected expert; the problem is that the conversion was only partial. The expert apparently retained the status of tribunal-appointed expert (the expert’s report was apparently submitted to the tribunal and only then provided to opposing counsel), but operated functionally more like a party-selected expert. The expert was thus permitted to engage in conduct that might raise questions about his independence or neutrality as a tribunal-appointed expert, but not subject to the procedures that would otherwise apply if he were a party-selected expert. For example, Senegal apparently did not have any opportunity to cross-examine the expert based on the report or to retain an opposing expert to challenge his conclusions. The only remedy proposed for Senegal was that it could somehow challenge the final conclusions of the expert. Such an opportunity is of limited value, however, without any opportunity to determine what information SOABI had provided during the ex parte meetings or to retain its own expert.

4.93  The problems in these cases demonstrate that the vague ethical guidance that exists for experts is designed around the established party-appointed/tribunal-appointed dichotomy. When these distinct roles are fused or combined, the already-vague standards become more difficult, if not impossible, to apply. These problems are especially acute when the role redefinition is partial, ad hoc, or not clearly articulated in advance.

4.94  Instead of parsing the unique duties that might be tied to distinct roles assigned to expert witnesses, most efforts to address expert ethics have ignored important differences. For example, to avoid potential concerns about differences between party-appointed and court-appointed experts, some commentators have suggested that all experts simply be required to be ‘neutral’ and ‘independent’ and ‘unbiased’.182 This one-size-fits-all approach is effectively what the IBA Evidence Rules, analysed earlier, attempt to do. Just as with arbitrators,183 however, generically applying terms like ‘independence’ for all expert witnesses cannot substitute for the hard work needed to delineate their specific inter-relational roles and consequent ethical responsibilities. Party-selected experts are compensated directly by the party who selected them and communicate directly with counsel about details of the case, including potentially confidential information about the party’s case strategy. This terminological confusion demonstrates that at least some ambiguities about experts’ ethical obligations are tied to a failure to match ethical obligations to their functional roles. If they are functioning in a role (p. 173) that is not actually independent of the parties and their counsel, imposing an ethical duty of ‘independence’ does not provide any meaningful guidance. The question remains, however, how to define their obligations and enforce them.

2. Oaths and certifications for experts

4.95  Another purpose of an oath, quite apart from criminal consequences for perjury, is to promote responsible testimony by impressing on the witness the moral obligation of truth-telling. The effect of oaths on the truthfulness of testimony seems to be one of very few topics on which there is no expert. As one commentator notes, ‘[s]urprisingly, psychologists have never examined whether the oath affects witness’ sincerity’.184 In the absence of direct testing regarding oaths, however, there is more than intuition to suggest the value of oaths on witness behaviour.

4.96  Social psychologists have done extensive testing of norm salience and its effect on behaviour. These studies have found some interesting results, which can be extrapolated to the context of witness oath-taking. For example, in one experiment students were demonstrably more cooperative in a game called ‘Community Game’, than other students when the same game was instead labelled ‘Wall Street Game’.185 Social psychologists conclude from this and other similar studies that situational cues can radically change people’s mental state about what is normatively appropriate in a social context.186

4.97  On the other hand, other experiments suggest that the potential benefits of such norm salience and norm compliance dissolve quickly when competing interests press on an actor’s immediate incentives. For example, in another study a group of religious ministry students were told that they were late for an extemporaneous talk across campus on the importance of helping those in need. Those ministry students tended not to stop and help a student lying in an overturned wheelchair. Their concern about being late overtook the norm of helping those in need, even if the potential speakers were undoubtedly considering precisely how to express that very norm at the same moment that they walked by the student in need.187 These findings have potentially important implications for how oaths could be effective in adjusting the professional conduct of expert witnesses.

4.98  Cumulatively, the previously described studies about the effect of norm salience combined with earlier observations about the limitiations of oaths suggest potential reforms for international arbitration. First, traditional oaths seem to have limited value in deterring irresponsible expert witness testimony. They are usually framed in stark true-false dichotomies and administered moments before testimony begins. The risk is that an oath applied in this (p. 174) manner may be regarded as an empty and ultimately irrational cultural ritual. As a result, it may be all that much easier to disregard.

4.99  On the other hand, an oath or certification that is substantively meaningful and strategically imposed to provide a ‘situational cue’ could potentially have more meaningful effects. An oath has more potential to operate as a situational cue when it is connected to larger reforms similar to those implemented in Canada and New South Wales.188 Those reforms enacted a ‘code’ or set of articulated norms regarding an expert’s obligation to aid the court in determining the truth. Those norms are provided to experts by counsel when they initially retain an expert as part of a code of ethics. The expert witness is then required to sign a certificate agreeing to be bound by those norms. These norms are framed in functional terms that seek to revise experts’ functional role by incorporating the oath into an expert witness’s professional undertaking. Oaths administered in this fashion also avoid the conventional true/false dichotomy that characterizes most oaths. Finally, to the extent the exercise is framed as a certification, it would appear also to avoid the prohibitions that some countries have against arbitrators administering oaths.

4.100  Like the religious ministry students ignoring a disabled student in need, it is of course possible that these norms may ultimately be ignored by party-selected experts. Nonetheless, having these self-regulated undertakings adopted at the beginning of proceedings, mutually acknowledged by counsel, and framed in more meaningful terms, make it more likely that they will become part of a process of acculturation into the international arbitration community.

4.101  Norms that are part of an acculturation process, as opposed to norms that are simply recited in an oath right before testimony is given, may be less readily discarded. More practically, early application will ensure they are applicable during the process of preparing reports and coordinating with counsel in anticipation of hearings. This approach to oaths may also put some pressure on counsel to restrain from putting undue pressure on experts to contort testimony. It is difficult, even for the most hardboiled of counsel, to participate in a process of communicating expert obligations and ensuring expert certification, only to turn around and ask an expert to blatantly violate the spirit, if not the letter, of those obligations.

4.102  In addition to using oaths to reacculturate experts, recently introduced structural reforms may help reorder the role of experts that make it inefficient or counterproductive to provide reckless expert evidence. The theory behind expert conferencing is that the effect (p. 175) of bias caused by attorney coaching can be diminished if experts are immediately confronted with the opinions and questions from peers.189 As one commentator describes, ‘[P]eople are less likely to lie in front of their peers’ and other experts are able to ‘identify over-simplifications in expert testimony’.190 In this sense, expert conferencing seeks to have immediate in-person peer review and provides a check on unethical excesses that vague ethical obligations with no meaningful enforcement mechanisms cannot.

4.103  Like using oaths as acculturation, witness hot-tubbing, witness conferencing, and expert teaming all seem to reorient the functional role of expert witnesses. These latter techniques expand expert witness functions beyond simply providing evidence in support of one party’s case to providing a direct check on an opposing witness. Some continue to doubt the efficacy of this new functional role191 while others appear to question whether functional roles can actually be reordered through these techniques.192 The growing interest and use of these techniques, however, suggests that arbitration specialists recognize that simply articulating ethical obligations for expert witnesses that have no means of real enforcement cannot resolve increasing concerns about potential ethical excesses.

D. Conclusion

4.104  International arbitration is still experimenting with expert witnesses, their functional roles, and their ethical obligations. While they suffer from some important shortcomings, the IBA Rules of Evidence are an important first attempt to regulate the conduct of experts. They clarify the distinction between party-selected and party-appointed experts, and attempt to delineate obligations attendant with each type of expert.

4.105  As procedural innovations become more entrenched practices, they will present new challenges in defining experts’ role and delineating the ethical obligations that attend that role. To that end, it is best to avoid the Frankenstein hybrids that combine expert witness functions (p. 176) with the role of advocates or the role of tribunals. These hybrids increase confusion about role and make it more difficult to determine proper professional obligations.

4.106  On the other hand, given the unique nature of expert witnessing, some of the best cures for the worst abuses require incorporating ethical reforms into structural changes that are directed at reacculturation in more carefully defined roles, such as the requirement that oaths be administered at the commencement of a case.


1  Guido Santiago Tawil, ‘Attacking the Credibility of Witnesses and Experts’, in The Art of Advocacy (2010) 453 (‘Use of party-appointed experts is a common and widely spread practice in international arbitration.’).

2  The 2007 gross revenues of just one global expert services company, LECG, were reported to be more than US$370 million. ‘LECG Corporation Reports Fourth Quarter 2007 Results, Marketwire’, 12 Feb. 2008, <http://www.marketwire.com>. See also Barry Schlachter, ‘Expert Witness Industry Booming’, Dallas-Fort Worth Star-Telegram, 13 May 2006, at F1 Several expert services companies (LECG, Navigant, Huron Group, and FT Consulting) are publicly traded.

3  See Jean-François Poudret and Sébastien Besson, Comparative Law of International Arbitration, 2nd edn. (Stephen Berti and Annette Ponti, trans., 2007) 662 (‘As numerous legal scholars have pointed out, evidence by expert opinion is one of those subjects where the differences between common law and civil law countries are most marked’) (citing Claude Reymond, ‘Conclusions’, in ‘L’Administration de la Preuve dans les Procédures Arbitrales Internationales’ [‘Taking of Evidence in International Arbitral Proceedings’] 167 (ICC Inst. Int’l Bus. L. & Prac., 1990) (Fr.); Jean-Francois Poudret, in Gerald Aksen, ‘Arbitrage et expertise’ [‘Arbitration and Expertise’] 135–6 (ICC Ins. Int’l Bus. L. & Prac, 1994) (Fr.); J.-F. Poudret, ‘Expertise et droit d’être entendu dans l’arbitrage international’, in Etudes de droit international en l’honneur de Pierre Lalive (1993) 607, 614 (Fr.); Axel Baum, ‘Reconciling Anglo-Saxon and Civil Law Procedure: The Path to a Procedural Lex Arbitrationis’, in R. Briner et al. (eds.), Recht der Internationalen Wirtschaft und Streiterledigung im 21. Jahrhundert: Liber Amicorum Karl-Heinz Böckstiegel [Law of International Business and Dispute Settlement in the 21st Century: Liber Amicorum: Karl-Heinz Böckstiegel] 21, 27 (Carl Heymanns Verlag, 2001)).

5  In comparative analysis of national legal systems, I use the term ‘adjudicatory decision-maker’, ‘adjudicator’ or ‘decision-maker’ to cover not only arbitral tribunals, but also juries, which are used most routinely in common law systems, but are also involved in certain criminal proceedings in some civil law systems. This chapter does not address ‘expert determinations’, which is not a form of arbitration. See Gary B. Born, International Arbitration: Law and Practice (Kluwer, 2012) 219.

6  See Mark Kantor, ‘A Code of Conduct of Party-Appointed Experts in International Arbitration—Can One Be Found?’ 849 PLI/Lit 191, 216 (2011).

7  ‘Moonlighting’ is a metaphor for a secondary job, which is usually performed in the late hours after completing a day’s work in a primary occupation.

8  There are, of course, so-called ‘professional experts’, meaning a person who spends all or most of their time serving as a witness or who testifies in large numbers of cases. Despite the terminology, so-called professional experts are not ‘professionals’ under sociological definitions of ‘professions’. See also Magli Sarfatti Larson, The Rise of Professionalism: A Sociological Analysis (1977) 55; Herbert M. Kirtzer, ‘The Professions Are Dead, Long Live the Professions: Legal Practice in a Post-professional World’, 33 L. & Soc’y Rev. 713, 716–8 (1999) (describing three definitions of the term ‘profession’).

10  See 4.64–4.65.

11  The extent and frequency of use of experts inevitably varies among different categories of cases, even within a single legal system. Inter-systemic empirical research is not available and would be difficult to conduct given the numerous independent variables. All available information, however, indicates that they are used in the vast majority of cases. In the United States, where there has been extensive empirical research, data suggests that expert testimony is pervasive. For example, a (not dated) sample of 529 civil trials in California in 1985 and 1986 revealed that expert testimony was used in 86% of cases, with an average of 3.3 experts per trial. See Samuel R. Gross, ‘Expert Evidence’, 1991 Wis. L. Rev. 1113, 1118–20 (1991).

12  As one famous US trial judge once lamented: ‘An expert can be found to testify to the truth of almost any factual theory, no matter how frivolous… [and] be used to obfuscate what would otherwise be a simple case.’ Jack B. Weinstein, ‘Improving Expert Testimony’, 20 U. Rich. L. Rev. 473, 482 (1986).

13  Joseph Sanders, ‘Expert Witness Ethics’, 76 Fordham L. Rev. 1539, 1539 (2007).

14  Although considered interchangeable, this chapter generally uses the term ‘party-selected expert’ both because it is more precise in that parties do not actually ‘appoint’ experts, but instead ‘retain’ or ‘select’ them. This nomenclature also avoids potential confusion with ‘party-appointed arbitrators’.

15  Robert W. Wachter, ‘Ethical Standards in International Arbitration: Considering Solutions to Level the Playing Field’, 24 Geo. J. Legal Ethics 1143, Tbl. 1, n. 97 (2011) (citing Regulation 31.22(l)(a) of the Uniform Civil Procedure Rules 2005 (NSW) (Austl.)).

16  See, e.g., Model Rules of Prof’l Conduct, R. 3.4(b) cmt. 3. (US). While US rules are probably the most flexible in terms of what they permit, even those rules prohibit compensation on a direct contingency fee basis (fees whose payment depends on the outcome of the case). This prohibition, however, only applies to attorneys making such payments, not the expert receiving it. The rule also prohibits lawyers from falsifying evidence or assisting a witness in false testimony. Some scholars argue that this rule should be interpreted as precluding attorneys from presenting expert testimony that is not scientifically valid, and as forbidding the lawyer to coax opinions from the expert that are beyond the realm of the expert’s specialized knowledge. On the other hand, it is possible, even if subject to strenuous objection, for experts to charge non-refundable retainers. See Steven Lubet, ‘The Rush to Remedies: Some Conceptual Questions About Nonrefundable Retainers’, 73 N.C. L. Rev. 271 (1994) (arguing that non-refundable retainers are ethically permissible); Lester Brickman and Lawrence A. Cunningham, ‘Nonrefundable Retainers Revisited’, 72 N.C. L. Rev. 1 (1993) (arguing in favour of a ban on non-refundable retainers). Most common law countries prohibit contingency fees altogether. See, e.g., SRA Code of Conduct 2011, arts. IB 1.27, OP 1.3 (UK); Legal Profession Act 2004 (NSW) s 325 (Austl.) (Although contingent fees are permitted for expert witnesses. See Regulation 31.22(l)(a) of the Uniform Civil Procedure Rules 2005 (NSW) (Austl.)); Janet Walker, ‘General Report’, in Marcel Storme et al., Dmitry Maleshin (ed.) Civil Procedure in Cross-Cultural Dialogue: Eurasia Context (2012), <http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2280682&download=yes>, 413, 439, 440, 452 (contingency fees prohibited in the Netherlands, Belgium, and Sweden). However, some jurisdictions are becoming more liberal in this respect. For example, Italy and Ontario recently removed their prohibitions on contingency fees. See Law no. 248/2006 (It.) (cited in Chiara Besso, ‘Italian National Report: The Italian litigation system: a civil law system with a touch of common law’, in Storme et al., Civil Procedure in Cross-Cultural Dialogue 269, 274; Janet Walker, ‘General Report’, in Storme et al., Civil Procedure in Cross-Cultural Dialogue 413, 436. In Germany, court-appointed expert witness fees are provided on an hourly rate set in the Expert Witness Compensation Act, but party-appointed fees and expert fees in arbitrations may be freely negotiated. See Volker Triebel and Heiko Plassmeier, ‘The Use of Experts in Litigation and Arbitration in Germany’, in D. Mark Cato, The Expert in Litigation and Arbitration (1999) 155, 160, ¶ 017. In France, expert fees are set by the court. See Robert Goldspink, ‘The Expert Witness in International Litigation’, Cato, The Expert in Litigation and Arbitration 141, 147, ¶ 052. Similarly, in Hong Kong, expert fees are a flat rate set by law. See District Court Civil Procedure (Fees) Rules, no. L.N. 17, (2009) (H.K.), <http://www.wipo.int/wipolex/en/text.jsp?file_id=187085>.

17  See Steven Lubet, ‘Expert Witnesses: Ethics and Professionalism’, 12 Geo. J. Legal Ethics 465, 469 (1999).

18  The Swiss Supreme Court has ruled that parties have a right to the appointment of an expert by the arbitral tribunal under certain conditions and that denial of the right is grounds for annulment. See Decision 4P.320/1994 of 6 September 1996; Decision 102 Ia 493, unpublished n. 8; Decision 4P.23/1991 of 25 May 1992 n. 5b. The right is so fundamental that the state may even provide experts in criminal cases. See Ake v Oklahoma, 470 US 68, 83 (1985). In the United States, courts have taken different views on the necessity of arbitrators. Compare Hesfibel Fiber Optik v Four S Group, 315 F. Supp.2d 1365 (D. Fla. 2004) (upholding arbitrator refusal to permit expert to testify), with Bordonaro v Merrill Lynch, Pierce, Fenner & Smith, 805 N.E.2d 1138 (Ohio App. 2004); Olan v Allstate Ins. Co., 622 N.Y.S.2d 33 (App. Div. 1995) (vacating award because of arbitrator’s refusal to allow expert testimony).

19  See Blake Fleetwood, ‘From the people who brought you the twinkie defense; the rise of the expert witness industry’, Wash. Monthly, 1 June 1987, <http://www.highbeam.com/doc/1G1-5010447.html>. For those not familiar, a ‘Twinkie’ is a popular, trademarked commercial American snack food renowned for its high sugar content and astoundingly long shelf-life, which is presumed to be attributable to excessive preservatives and other chemicals.

20  Some of the most controversial uses of experts in the United States have arisen in this context, as prosecutors have sought to build cases on some forms of expert testimony that have been determined to be inherently unreliable, such as experts who purport to be able to predict the future dangerousness of sexual offenders.

21  Many US courts have flat-out rejected as unreasonable complaints concerning highly technical subject matter filed by attorneys without consulting an expert. See Dennis R. Suplee et al., The Expert Witness: Law and Practice (The Pennsylvania Bar Institute, 1999) 17–18; see also Shelly Brinker, ‘Opening the Door to the Indeterminate Plaintiff: An Analysis of the Causation Barriers Facing Environmental Toxic Tort Plaintiffs’, 46 UCLA L. Rev. 1289 (1999); Tahirih V. Lee, ‘Court-Appointed Experts and Judicial Reluctance: A Proposal to Amend Rule 706 of the Federal Rules of Evidence’, 6 Yale L. & Pol’y Rev. 480, 488–92 (1988). Arguably, some investment arbitrations resemble mass toxic tort claims, though in reverse, with alleged environmental harms or risks to health and safety operating as defences against investor claims of improper state conduct. See, e.g., Compañiá del Desarrollo de Santa Elena, S.A. v Costa Rica, ICSID Case No. ARB/96/1, (2000) 15:1 ICSID Review FILJ, ¶ 72; Sebastian Perry, ‘US Limestone Investor Sues Oman’, Global Arb. Rev. (13 Dec. 2011); Andrew Newcombe, ‘The Boundaries of Regulatory Expropriation in International Law’, 4 Transnat’l Disp. Mgmt. (July 2007); David A. Gantz, ‘Reconciling Environmental Protection and Investor Rights Under Chapter 11 of NAFTA’, 31 Envtl. L. Rep. 10646 (2001); J. Martin Wagner, ‘International Investment, Expropriation and Environmental Protection’, 29 Golden Gate U. L. Rev. 465 (1999); Julie A. Soloway, ‘Environmental Regulation as Expropriation’, 33 Can. Bus. L.J. 92 (1999).

22  This view has been echoed by other authorities. See Kirk v Raymark Indus. Inc., 61 F.3d 147, 164 (3d Cir. 1995) (‘In theory, despite the fact that one party retained and paid for the services of an expert witness, expert witnesses are supposed to testify impartially in the sphere of their expertise.’).

23  For an extended discussion of how abstract, value-laden terms can ‘lose their meaning and fail to provide meaningful guidance’, see paras 8.72–8.73.

24  See Carol Pogash, ‘Myth of the “Twinkie defense”: The verdict in the Dan White case wasn’t based on his ingestion of junk food’, San Francisco Gate, 23 Nov. 2003, <http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/11/23/INGRE343501.DTL>; Blake Fleetwood, ‘From the people who brought you the twinkie defense; the rise of the expert witness industry’, Wash. Monthly, 1 June 1987, <http://findarticles.com/p/articles/mi_m1316/is_v19/ai_5010447/>. The so-called ‘twinkie defence’ is a derisive term for the theory, advanced through experts, that the accused in a high profile political assassination was not responsible for his actions because he was depressed from eating too much junk food. Actually, this reference is a myth. The defence argued that junk food was a symptom of depression, not the cause.

25  Christian Borris, ‘The Reconciliation of Conflicts Between Common Law and Civil Law Principles in the Arbitration Process’, in Stefan N. Frommel and Barry A.K. Rider (eds.), Conflicting Legal Cultures in Commercial Arbitration: Old Issues and New Trends (1999) 147, 161; Marijke Malsch and Ian Freckelton, ‘Expert Bias and Partisanship: A Comparison Between Australia and the Netherlands’, 11 Psychol. Pub. Pol’y & L. 42, 46–47 (2005); Murat Ozsunay, ‘Turkish National Report’, in Storme et al, Civil Procedure in Cross-Cultural Dialogue 323.

26  See Goldspink, ‘The Expert Witness in International Litigation’, 141, 141–5; David Leonard, ‘The Expert in Hong Kong and Mainland China’, in Cato, The Expert in Litigation and Arbitration 321, 328.

27  See Aldo Berlinguer and Vincenzo Vigoriti, ‘The Expert Witness in Italian Litigation and Arbitration’ (A.D.R. Colvin trans.), in Cato, The Expert in Litigation and Arbitration 185, 187.

28  See Sven Timmerbeil, ‘The Role of Expert Witnesses in German and U.S. Civil Litigation’, 9 Ann. Surv. Int’l & Comp. L. 163, 173–74 (2003).

29  See Timmerbeil, ‘The Role of Expert Witnesses in German and U.S. Civil Litigation’, 174 (citing German Civil Procedure Code (ZPO) §§4245).

30  Teresa Arruda Alvim Wambier, ‘Brazilian National Report: Brazilian civil procedure: between common law and civil law?’ in Storme et al., Civil Procedure in Cross-Cultural Dialogue 253, 262, <http://ssrn.com/abstract=2280682>.

31  See Samuel R. Gross, ‘Expert Evidence’, 1991 Wis. L. Rev. 1113, 1188 (1991).

32  See Gross, ‘Expert Evidence’, 1181; E. Donald Elliott, ‘Toward Incentive-Based Procedure: Three Approaches for Regulating Scientific Evidence’, 69 B.U. L. Rev. 487, 493 (1989).

33  Empirical research in which participants were given one of three different versions of a trial transcript (without expert testimony, with plaintiff expert testimony only, and one containing a ‘battle’ between experts) showed that jurors unaided by expert testimony awarded significantly less, and that jurors tended to match the values suggested by experts, and, in the case of a battle of experts, jurors tended not to compromise between expert values (instead, jurors preferred one over the other). See Allan Raitz et al., ‘Determining Damages: The Influence of Expert Testimony on Jurors’ Decision Making’, 14 Law & Hum. Behav. 385 (1990).

34  While arbitrators are more sophisticated than jurors, as analysed in more detail in Chapter 7, arbitrators, like judges, are subject to other cognitive biases, such as anchoring, framing, hindsight bias, the representativeness heuristic, and egocentric biases. See paras 8.08–8.09.

35  While there had been some support at common law for a notion that judges had the power to appoint expert witnesses, Federal Rule of Evidence 706 sought more directly to respond to concerns about expert-shopping, expert venality, and the reluctance of many reputable experts to involve themselves in litigation. See Fed. R. Evid. 706 advisory committee’s note. See also Lee, ‘Court-Appointed Experts and Judicial Reluctance’, 480. For an older source that predates the reform, see John M. Sink, ‘The Unused Power of a Federal Judge to Call His Own Expert Witnesses’, 29 S. Cal L. Rev. 195 (1956).

36  Karen Butler Reisinger, Note, ‘Court-Appointed Expert Panels: A Comparison of Two Models’, 32 Ind. L. Rev. 225, 234 (1998).

37  See, e.g., Bert Black et al., ‘Science and the Law in the Wake of Daubert: A New Search for Scientific Knowledge’, 72 Tex. L. Rev. 715, 795–6 (1994); Joe S. Cecil and Thomas E. Willging, ‘Accepting Daubert’s Invitation: Defining a Role for Court-Appointed Experts in Assessing Scientific Validity’, 43 Emory L.J. 995 (1994).

38  ‘A survey of federal judges revealed that 81% had never appointed an expert under FRE 706, and only 8% had appointed a court expert more than one time.’ See Timmerbeil, ‘The Role of Expert Witnesses in German and U.S. Civil Litigation’ 168.

39  Federal Rule of Evidence 706 provides several checks on expert testimony, including requiring that the expert testify at trial, that the expert inform the parties of any findings, that the parties have an opportunity to depose and cross-examine the expert, and that the court delineates the duties of the expert in written form made available to the parties. Moreover, the court’s appointment decision is reviewable on appeal.

40  In another survey, 37% of state court judges (judges who preside at courts in the legal systems of the individual states) surveyed indicated that they believed that court-appointed experts could save both the courts and litigants time and money. See Stephanie Domitrovich et al., ‘State Trial Judge Use of Court Appointed Experts: Survey Results and Comparisons’, 50 Jurimetrics J. 371, 388–9 (2010). Despite this belief, judges are reluctant to appoint experts because of the cost, concerns about procedural fairness, and bias potential from court-appointed experts.

41  Joe S. Cecil and Thomas E. Willging, ‘Court-Appointed Experts,’ in 33-SE 2 Reference Manual on Scientific Evidence, 2nd edn., § VII (Fed. Judicial Ctr., 2000). See also Joe S. Cecil and Thomas E. Willging, ‘Accepting Daubert’s Invitation: Defining a Role for Court-Appointed Experts in Assessing Scientific Validity’, 43 Emory L.J. 995, 1019 (1994); Douglas H. Ginsburg, ‘Appellate Courts and Independent Experts’, 60 Case W. Res. L. Rev. 303, 304 (2010) (judge/author arguing that it would be ‘a mistake for the federal courts of appeals to retain or consult experts’ because, among other things, the practice is ‘inconsistent with the adversary system’).

42  Kenneth S. Broun, ‘Proposals for improvement of the practice relating to expert testimony’, 1 McCormick on Evidence, 6th edn., § 17 (2006).

43  The Standards themselves are available at <http://www.abanow.org/2011/07/2011am101b/> (announcing passage of resolution adopting Standards).

44  See Memorandum, 2011 Annual Meeting of the American Bar Association and Meeting of the House of Delegates, 2 Sept. 2011, 19. (On behalf of the Section of Litigation, Lawrence J. Fox of Pennsylvania withdrew Resolution 101B adopting the Standards of Conduct for Experts Retained by Lawyers, dated August 2011.)

45  See Mark Hansen, ‘Three Strikes: Litigation Section Drops Proposal for Guidelines on Dealing with Expert Witnesses’, ABA J., 1 Nov. 2012, <http://www.abajournal.com/mobile/mag_article/three_strikes_ litigation_section_drops_proposal_for_guidelines_on_experts>.

46  ABA authority over the legal profession is indirect because its power is limited to promulgating Model Rules, which are then either adopted or not (or, as is most often the case, adopted with amendments) by states, which then make the rules binding on attorneys licensed in those states. For an overview of the ABA’s function in promulgating the Model Rules, see Am. Bar Assoc., Constitution and Bylaws, art. 11 (2011–12); Quintin Johnstone, ‘Bar Associations: Policies and Performance’, 15 Yale L. & Pol’y Rev. 193, 228 (1996).

47  ABA Standards of Conduct for Experts Retained by Lawyers, intro. (Aug. 2011).

48  An attorney often acts as a client’s agent in selecting expert witnesses and facilitating their retention on behalf of the client. Attorneys are not, however, permitted to retain and compensate experts directly in most US jurisdictions, except for general expenses and compensation permitted by law. See Model Rules of Prof’l Conduct, R. 3.4(b) cmt. 3; David L. Faigman et al., Modern Scientific Evidence: The Law and Science of Expert Testimony (West, 2009–10) § 3:13; Lawrence J. Fox and Bruce Green, ‘Ethical Issues in Dealing with Experts’, in Wendy Gerwick Couture and Allyson W. Haynes (eds.), Litigators on Experts: Strategies for Managing Expert Witnesses from Retention through Trial (2010) 126, 127–8, 134–5.

49  Karen L.K. Miller, ‘Zip to Nil?: A Comparison of American and English Lawyers’ Standards of Professional Conduct’, 32 ALI-ABA 199, 199–223, 204 (1995).

50  See The Right Honourable the Lord Woolf, Access To Justice (1995) ch. 23, ¶ 10, available at <http://www.dca.gov.uk/civil/interim/chap23.htm> (quoting journal Counsel for November/December 1994). See also The Right Honourable the Lord Woolf, Master of the Rolls, Access to Justice: Final Report to the Lord Chancellor on the Civil Justice System in England and Wales (1996), <http:/www.dca.gov.uk/civil/final/index.htm>.

51  See Civil Procedure Rules, rule 35.3 (2005) (Eng.), <http://www.justice.gov.uk/courts/procedure-rules/civil/rules/part35> (providing that ‘the duty of an expert [is] to help the court on the matters within their expertise’ and that ‘[t]his duty overrides any obligation to the person from whom experts have received instructions or by whom they are paid’).

52  Compare John Peysner and Mary Seneviratne, Dep’t for Constitutional Affairs, The Management of Civil Cases: The Courts and Post-Woolf Landscape (2005), <http://www.dca.gov.uk/research/2005/9_2005_full.pdf> (reporting a significant reduction in the ‘hired gun’ approach to expert witnessing), with M. Herman, ‘Success of Woolf reforms limited, research claims’, Times Online, 26 July 2006 (claiming Woolf reform has failed in its objective to make litigation less complex and more accommodating, with shorter, more predictable timescales and more affordable costs for those with limited financial means). For further discussion of the utility of oaths as applied to expert witnesses, see paras 4.71–4.81.

53  For example, the Federal Court of Australia has issued guidelines to attorneys who propose retaining an expert to prepare a report or give evidence in a proceeding: ‘1. General Duty to the Court: 1.1 An expert has an overriding duty to assist the court on matters relevant to the expert’s area of expertise. 1.2 An expert witness is not an advocate for a party even when giving testimony that is necessarily evaluative rather than inferential. 1.3 An expert witness’s paramount duty is to the court and not to the person retaining the expert.’ See Fed. Ct. of Austl., Guidelines for Expert Witnesses in Proceedings in the Federal Court of Australia (2007), <http://www.fedcourt.gov.au/law-and-practice/practice-documents/practice-notes/cm7>.

54  Mariam J. Masid, ‘Hydrology and the Courts: The Role of Expert Witnesses—A Study on Potential Reforms’, 11 U. Denv. Water L. Rev. 1, 9–10 (2007).

55  See Federal Courts Rules, SOR/98-106, R. 52.2, Form 52.2, sched. (2010) (Can.), <http://canlii.ca/t/l9vm>; ‘Rules Amending the Federal Courts Rules (Expert Witnesses)’, 143 Can. Gazette (17 Oct. 2009), <http://www.gazette.gc.ca/rp-pr/p1/2009/2009-10-17/html/reg1-eng.html>.

56  See, e.g., Doug Jones, ‘Party Appointed Experts: Can They be Usefully Independent?’ 8(1) Transnat’l Disp Mgmt. 1, 10–11 (2011); Yuka Fukunaga, ‘Chapter 5: Experts in WTO and Investment Litigation’, in Jorge A. Huerta-Goldman, Antoine Romanetti, et al. (eds.), 43 WTO Litigation, Investment Arbitration, and Commercial Arbitration, Global Trade Law Series (Kluwer, 2013) 135, 158; Harris Bor, ‘Chapter 24: Expert Evidence’, in Julian D.M. Lew, Harris Bor, et al. (eds.), Arbitration in England, with chapters on Scotland and Ireland (Kluwer, 2013) 503, 508–09; Jeff Waincymer, Procedure and Evidence in International Arbitration (Kluwer, 2012) 967–72, § 12.14.11–14; Born, International Arbitration 170; Antonio Hierro, ‘Reducing Time and Costs in ICC International Arbitration Excess Time and Costs of Arbitration: An Incurable Disease?’ 2012 Spain Arb. Rev. 37, 45 (2012); Caroline E. Foster, Science and the Precautionary Principle in International Courts and Tribunals: Expert Evidence, Burden of Proof and Finality (Cambridge University Press, 2011) 123–25; David Sonenshein and Charles Fitzpatrick, ‘The Problem of Partisan Experts and the Potential for Reform Through Concurrent Evidence’, 32 Rev. Litig. 1, 55–62 (2013); Elizabeth Reifert, Comment, ‘Getting into the Hot Tub: How the United States Could Benefit from Australia’s Concept of “Hot Tubbing” Expert Witnesses’, 89 U. Det. Mercy L. Rev. 103 (2011); Frances P. Kao et al., ‘Into the Hot Tub … A Practical Guide to Alternative Expert Witness Procedures in International Arbitration’, 44 Int’l Law. 1035 (2010); Adam Liptak, ‘In US, Expert Witnesses Are Partisan’, N.Y. Times, 11 Aug. 2008, <http://www.nytimes.com/2008/08/12/us/12experts.html?pagewanted=all8_r=0>; Lisa C. Wood, ‘Experts Only: Out of the Hot Tub and into the Joint Conference’, 22-Fall Antitrust 89 (2007).

57  See Patricia D. Galloway, ‘Using Experts Effectively & Efficiently in Arbitration’, 67-OCT Disp. Resol. J. 26, 33 (2012); Kao et al., ‘Into the Hot Tub … A Practical Guide to Alternative Expert Witness Procedures in International Arbitration’, 1037.

58  See., e.g., Galloway, ‘Using Experts Effectively & Efficiently in Arbitration’ 245 n. 295 (‘The hot tub might place undue emphasis on the general appeal of an expert, rather than the solidity of the positions he or she is endorsing.’); Mark Kantor, Valuation for Arbitration (2008) 300–1; Wood, ‘Experts Only: Out of the Hot Tub and into the Joint Conference’.

59  Wolfgang Peter, ‘Witness Conferencing Revisited’, in S. Bond (ed.), Arbitral Procedure at the Dawn of the New Millenium, Reports of the International Colloquium of CEPANI (2004) 156 et seq.

60  See, e.g., Seven Network Ltd. v News Ltd. [2007] FCA 1062, on appeal [2009] FCAFC 166 (Austl.).

61  See Federal Court Rules, Select Legislative Instrument 2011 No. 134, § 23.15 (2011) (Austl.), <http://www.comlaw.gov.au/Details/F2011L01551/Html/Text#_Toc297989801> Supreme Court New South Wales, Practice Note SC Gen 11: Supreme Court—Joint Conferences of Expert Witnesses (17 Aug. 2005), <http://www.lawlink.nsw.gov.au/practice_notes/nswsc_pc.nsf/a15f50afb1aa22a9ca2570ed000a2b08/991e2f2f3bcd8289ca2572ed000cec4b>.

62  Wood, ‘Experts Only: Out of the Hot Tub and into the Joint Conference’.

63  The IBA Rules on the Taking of Evidence in International Commercial Arbitration (2010), Article 5.4, specifically recommends joint conferencing where experts have submitted reports on ‘the same or related issues’.

64  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 79.

65  Malsch and Freckelton, ‘Expert Bias and Partisanship’, 45.

66  See, e.g., Rupert Jackson, ‘Review of Civil Litigation Costs: Final Report’, The Stationary Office, ch. 38 s 3, 379–84 (2009), <http://www.judiciary.gov.uk/NR/rdonlyres/8EB9F3F3-9C4A-4139-8A93-56F09672EB6A/0/jacksonfinalreport140110.pdf> (analysing in detail the effects of the Woolf Reforms in England and Wales, criticizing their effectiveness concerning experts, and posing suggestions for improvement); Doug Jones, ‘Party Appointed Expert Witnesses in International Arbitration: A Protocol at Last’, 24 Arb. Int’l 137, 154 (2008) (discussing the rejection of Woolf Report suggestions for appointment of a single expert in Australia and international arbitration); John Hansen, Lecture, ‘Courts Administration, the Judiciary and the Efficient Delivery of Justice: A Personal View’, 11 Otago L. Rev. 351, 371 (2005–08) (criticizing that Woolf Reforms do not go far enough and that more fundamental changes are necessary to improve access to justice in New Zealand); NSW Law Reform Commission, Report 109: Expert Witnesses (June 2005) (criticizing the Woolf Report’s suggestions concerning disclosure of all communications between the parties and experts and determining that the policy reasons for maintaining client legal privilege over such communications outweighed the potential benefits of disclosure); Gary Edmond, ‘After Objectivity: Expert Evidence and Procedural Reform’, 25 Sydney L. Rev. 131 (2003) (deconstructing basic premises of Woolf-esque reforms in England and Australia and challenging that reforms threaten to surreptitiously raise admissibility standards, contribute to the transformation of the judicial role, privilege repeat litigants, and increase the vulnerability of the judiciary to exogenous criticism).

67  Recent ‘discoveries’ about the humanness of judges, and by extension arbitrators, is taken up later in Chapter 7.

68  See Christopher Tarver Robertson, ‘Blind Expertise’, 85 N.Y.U. L. Rev. 174, 185–86 (2010) (illustrating how anchoring may affect expert witnesses).

69  Robertson, ‘Blind Expertise’, 185–6 (reporting on the outcome of empirical research).

70  Ellen E. Deason, ‘Court-Appointed Expert Witnesses: Scientific Positivism Meets Bias and Deference’, 77 Or. L. Rev. 59, 101–2 (1998). One potential mechanism for reducing this type of error is to appoint multiple experts. See E. Donald Elliott, ‘Toward Incentive-Based Procedure: Three Approaches for Regulating Scientific Evidence’, 69 B.U. L. Rev. 487, 504 (1989).

71  Stephen Jay Gould, The Mismeasure of Man (1981) 21–2.

72  In contrast, fact witnesses testify regarding their perception of the observable facts. Often, they are either precluded from giving opinions regarding the interpretation of such facts or any such opinions are discounted by the factfinder.

73  ‘[A]scriptions such as impartial, neutral or objective are not productive ways to think about expertise and expert knowledge, especially in relation to legal procedural reform.’ Gary Edmond, ‘After Objectivity: Expert Evidence and Procedural Reform’, 133.

74  Even in the so-called hard sciences, scientific inquiries speak in terms of ‘theories’ not ‘facts’. A theory is a body of consistent scientific knowledge that has not yet been disproved by experiment. In experimental sciences, a theory can never be ‘proved’, it can only be ‘disproved’ by experiment. Gravity, for example, is a theory, not a fact, despite its almost universal acceptance. See Matthew Cutchen, ‘Selman v Cobb County School District: The Evolution of Establishment Clause Jurisprudence’, 7 Rutgers J. L. & Religion 9, 40–1 (2006); Stephen Jay Gould, ‘Darwinism Defined: The Difference Between Fact and Theory’, 8 Discover 64, 64 (Jan. 1987) (‘Facts are the world’s data; theories are explanations proposed to interpret and coordinate facts.’).

75  One study found that only 3% of judges and juries decided cases inconsistent with the opinions of experts. Joe S. Cecil and Thomas E. Willging, ‘Court-Appointed Experts’, in Reference Manual on Scientific Evidence (New York, 2000) 528, 553. See also Gerald Walpin, ‘America’s Adversarial and Jury Systems: More Likely to Do Justice’, 26 Harv. J.L. & Pub. Pol’y 175, 182 (2003) (commenting that use of a single expert can obscure any divergent views from the court).

76  It is perhaps for these reasons that international tribunals rarely rely on a single court-appointed expert. The power to appoint experts at its own initiative was used only once each by the Permanent Court of International Justice (see Case Concerning the Factory at Chorzów (Germany v Poland), Claim for Indemnity—Merits (1928) PCIJ Series A, No. 13, para. 8; Order of 13 Sept. 1928, PCIJ Series A, No. 17) and the International Court of Justice (see Corfu Channel case (United Kingdom v Albania), Order of 17 Dec. 1948, ICJ Rep. 1947–1948.

77  Gary Edmond, ‘After Objectivity: Expert Evidence and Procedural Reform’, (arguing that procedural reforms are based on ‘simplistic images of objectivity’ and that expert evidence reforms threaten to raise admissibility standards, privilege repeat litigants, and transform the judicial role).

78  See Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 172. By contrast, in an adversarial system, party-selected experts have an incentive to identify and expose the errors of an opposing expert, as well as the knowledge, skills, and professional credibility to do so—sometimes to the detriment of both parties. See Brian L. Cutler and Steven D. Penrod, Mistaken Identification: The Eyewitness, Psychology, and the Law (Cambridge University Press, 1995); Lora M. Levett and Margaret Bull Kovera, ‘The Effectiveness of Opposing Expert Witnesses for Educating Jurors about Unreliable Expert Evidence’, 23 Law & Hum. Behav. 363, 363 (2008) (‘The presence of opposing expert testimony caused jurors to be sceptical of all expert testimony rather than sensitizing them to flaws in the other expert’s testimony.’); Jennifer L. Devenport and Brian L. Cutler, ‘Impact of defense-only and opposing eyewitness experts on juror judgments’, 28 Law & Hum. Behav. 569 (2004) (‘Expert testimony did not significantly influence juror judgments, but the opposing expert testimony diminished the credibility of the defence expert in the eyes of the jurors.’).

79  D. Mark Cato, ‘Interlocutory and Hearing Problems and the Expert Witness’, in The Expert in Litigation and Arbitration (1999) 587, 631–4 (discussing computer software copyright infringement case where tribunal-appointed expert drastically simplified lengthy reports of party-appointed experts). See also Michael P. Reynolds, The Expert Witness in Construction Disputes (2002) 111 (citing Abbey National Mortgages and Others v Key Surveyors Nationwide and Others [1996] 1 WLR 1534; tribunal used same logic as computer software case in Cato, but in construction case).

80  Fed. R. Evid. 706 advisory committee’s note.

81  Robertson, ‘Blind Expertise’, 199.

82  See Sven Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 166 (2003) (‘In the end, the fact finder has to decide which ‘story’, or testimony, is more plausible.’); Eric Ilhyun Lee, ‘Expert Evidence in the Republic of Korea and Under the US Federal Rules of Evidence: A Comparative Study’, 19 Loy. L.A. Int’l & Comp. L.J. 585, 617 (1997) (‘Like a US jury, a Korean court is free to reject expert testimony and may render a decision contrary to the expert’s opinion.’); Robert F. Taylor, ‘A Comparative Study of Expert Testimony in France and the United States: Philosophical Underpinnings, History, Practice, and Procedure’, 31 Tex. Int’l L.J. 181, 202–3 (1996).

83  Robertson, ‘Blind Expertise’, 198–9; Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 180 (2003) (‘Too much depends on the court expert, and in many cases, it is not the judge but the court expert who decides the case.’).

84  See Ruth Fenton, ‘A Civil Matter for A Common Expert: How Should Parties and Tribunals Use Experts in International Commercial Arbitration?’ 6 Pepp. Disp. Resol. L.J. 279, 281 (2006) (discussing use of party-appointed experts in the Netherlands); Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 177–81 (2003) (describing use of party-appointed experts in Germany); Goldspink, ‘The Expert Witness in International Litigation’, 141 (discussing party-appointed experts in Germany).

85  See Malsch and Freckelton, ‘Expert Bias and Partisanship’ (research has shown that defence lawyers in the Netherlands do not often make use of the few opportunities they have to request an ‘own’ expert); Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 177–8; Goldspink, ‘The Expert Witness in International Litigation’, 144; Lee, ‘Court-Appointed Experts and Judicial Reluctance’, 492–4.

86  Malsch and Freckelton, ‘Expert Bias and Partisanship’, 47; Lee, ‘Court-Appointed Experts and Judicial Reluctance’, 492–4.

87  See Timmerbeil, ‘The Role of Expert Witnesses in German and US Civil Litigation’, 177–78 (2003).

88  This is particularly true for investor-state arbitration. See Christopher Shreuer, ‘The Relevance of Public International Law in International Commercial Arbitration: Investment Disputes’, <http://www.univie.ac.at/intlaw/pdf/csunpublpaper_1.pdf> (unpublished manuscript).

89  Even the procedures of investor-state arbitrations which generally arise from treaty terms tend to be more flexible than those of public international courts. See Donald Francis Donovan, ‘The Relevance (or Lack Thereof) of the Notion of “Mandatory Rules of Law” to Investment Treaty Arbitration’, 18 Am. Rev. Int’l Arb. 205 (2007); Susan D. Franck, ‘The Legitimacy Crisis in Investment Treaty Arbitration: Privatizing Public International Law Through Inconsistent Decisions’, 73 Fordham L. Rev. 1521, 1536–37 (2005) (describing the comparative lack of remedies in public international law versus international investment arbitration).

90  See, e.g., International Court of Justice, Rules of Court, arts. 51, 67 (adopted 14 Apr. 1978, entered into force 1 Jul.1978) (ICJ Rules) (outlining procedure for the tribunal to appoint experts); Iran–United States Claims Tribunal Final Rules of Procedure, 3 May 1983, 1 Iran–US CTR 57, art. 27 (same); North American Free Trade Agreement (signed 17 Dec. 1992, entered into force 1 Jan. 1994) 32 ILM 289, 605, art. 2014 (same); European Union, Rules of Procedure of the Court of Justice (signed 25 Sept. 2012, entered into force 1 Nov. 2012) OJ L 265, arts. 64, 70 (same); World Trade Organization, Understanding on Rules and Procedures Governing the Settlement of Disputes, art. 13, App. 4 and explanation to app. 4 (1994), <https://www.wto.org/english/docs_e/legal_e/28-dsu_e.htm> (same).

91  See, e.g., The Corfu Channel case (United Kingdom v Albania) Order of 17 December 1948, ICJ Rep. 1947–1948 124; Judgment of 9 April 1949, ICJ Rep. 1949 (ICJ case); European Communities—Measures Concerning Meat and Meat Products (Hormones), Complaint by Canada (WT/DS48), Complaint by the United States (WT/DS26) (cited in Foster, Science and the Precautionary Principle in International Courts and Tribunals 113) (WTO case). The two-phase WTO procedures for expert evidence (discussed in this section) have allowed tribunal-appointed experts and party-selected experts to indirectly discuss evidence. See, e.g., Canada—Continued Suspension of Obligations in the EC—Hormones Dispute, Complaint by the EC (WT/DS321); Report of the Panel, Report of the Appellate Body, adopted 14 Nov. 2008, paras 252–7, 1056–7 (WTO case).

92  See ICJ Statute, art, 34(2); ICJ Rules, art. 69(4). See e.g., WHO, Effects of Nuclear War on Health and Health Services, 2nd edn. (1987), cited in Legality of the Use by a State of Nuclear Weapons in Armed Conflict (Advisory Opinion), 8 July 1996, ICJ Rep. 1996 66, 78.

93  See, e.g., European Communities—Measures Concerning Meat and Meat Products (Hormones), Complaint by Canada (WT/DS48), para. 6.7, Complaint by the United States (WT/DS26), para. 6.8 (consulting secretariats of the Convention on Biological Diversity, the Codex Alimentarius Commission, the Food and Agriculture Organization of the United Nations, the International Plant Protection Convention, theWorld Organisation for Animal Health, the United Nations Environment Programme, and the WHO) (cited in Foster, Science and the Precautionary Principle in International Courts and Tribunals 103); Canada—Continued Suspension of Obligations in the EC—Hormones Dispute, Annex E (consulting the Codex Alimentarius Commission, the Joint Expert Committee on Food Additives of the Food and Agriculture Organization and the WHO, and the International Agency for Research on Cancer).

94  See, e.g., Case concerning Pulp Mills on the River Uruguay (Argentina v Uruguay), Public sitting held on Monday 28 September 2009, CR 2009/20 (trans.), paras 31–32 (Argentina arguing that one of the experts consulted by a so-called neutral international organization was not ‘independent’).

95  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 88–44 (discussing the use and limitations of experts as advocates before international courts and tribunals).

96  Case concerning the Gabcıkovo-Nagymaros Project (Hungary/Slovakia), Judgment of 25 Sept. 1997 ICJ Rep. 1997.

97  Verbatim Record, 25 Mar. 1997, 10.00am, 39 (cited in Foster, Science and the Precautionary Principle in International Courts and Tribunals 89).

98  Case concerning Pulp Mills on the River Uruguay (Argentina v Uruguay), Request for the Indication of Provisional Measures, Order of 13 July 2006 ICJ Rep. 2006.

99  Verbatim Record, 22 Sept. 2009 (trans.) 2 (cited in Foster, Science and the Precautionary Principle in International Courts and Tribunals 89).

100  See ICJ Rules, art. 64.

101  See Pulp Mills, Separate Opinion of Judge Greenwood, para. 27; Foster, Science and the Precautionary Principle in International Courts and Tribunals 90–41.

102  See Pulp Mills, Separate Opinion of Judge Greenwood, para. 28.

103  See generally, Foster, Science and the Precautionary Principle in International Courts and Tribunals 125–49; Ruth Fenton, ‘A Civil Matter for A Common Expert: How Should Parties and Tribunals Use Experts in International Commercial Arbitration?’ 6 Pepp. Disp. Resol. L.J. 279, 283-85 (2006).

104  See Joost Pauwelyn, ‘The Use of Experts in WTO Dispute Settlement’, 51 Int’l & Comp. L.Q. 325, 345 (2002).

105  See Statute of the International Court of Justice, arts. 30, 50 (1945) (ICJ Statute); ICJ Rules, arts. 9, 67; United Nations Convention on the Law of the Sea, art. 289 (1982) (UNCLOS).

106  See Fenton, ‘A Civil Matter for A Common Expert’ 283.

107  Pauwelyn, ‘The Use of Experts in WTO Dispute Settlement’ 345.

108  Dana H. Freyer, ‘Assessing Expert Evidence’, in Lawrence W. Newman and Richard D. Hill (eds.), The Leading Arbitrators’ Guide to International Arbitration, 2nd edn. (2008) 429, 436.

109  See, e.g., Permanent Court of Arbitration, Optional Rules for Arbitration of Disputes Relating to Natural Resources and/or the Environment, art. 8(3) (2012) (‘For the purpose of assisting the parties and the appointing authority the Secretary-General will make available a list of persons considered to have expertise in the subject-matters of the dispute at hand for which these Rules have been designed.’); UNCLOS, annex VIII (outlining procedure for assembling special arbitral panels consisting of scientific experts chosen from a permanent list).

110  See UNCLOS, annex VIII, art. 2; Christopher C. Joyner, ‘Compliance and Enforcement in New International Fisheries Law’, 12 Temp. Int’l & Comp. L.J. 271, 297 (1998).

111  See Andrew W. Jurs, ‘Balancing Legal Process with Scientific Expertise: Expert Witness Methodology in Five Nations and Suggestions for Reform of Post-Daubert U.S. Reliability Determinations’, 95 Marq. L. Rev. 1329, 1389–90 (2012) (describing use of expert lists in Germany); Jean de Hautecloque, ‘French Judicial Expertise Procedure and International Arbitration’, 4 J. Int’l Arb. 77, 79 (1987) (same in France).

112  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 127.

113  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 114–43; Theofanis Christoforou, ‘Settlement of Science-Based Trade Disputes in the WTO: A Critical Review of the Developing Case Law in the Face of Scientific Uncertainty’, 8 N.Y.U. Envtl. L.J. 622, 631–32 (2000). See also WTO Dispute Panel Report on EC Measures Concerning Meat and Meat Products (Hormones), 18 Aug. 1997, WT/DS26/R/USA, paras 6.5–6.9; WTO Dispute Panel Report on United States—Import Prohibition of Certain Shrimp and Shrimp Products, 15 May 1998, WT/DS58/R, paras 5.8–5.9.

114  The procedure outlined here has evolved largely due to party request and experience, as the WTO rules concerning expert review are extremely broad and flexible. See WTO, Understanding on Rules and Procedures Governing the Settlement of Disputes, art. 13, App. 4 and explanation to app. 4 (1994), <https://www.wto.org/english/docs_e/legal_e/28-dsu_e.htm>.

115  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 119–40.

116  See Mirjan Damaska, ‘The Uncertain Fate of Evidentiary Transplants: Anglo-American and Continental Experiments’, 45 Am. J. Comp. L. 839, 839 (1997) (noting that ‘[i]nspiration for procedural reform is increasingly sought in the legal thesaurus of foreign countries’). Comparativists have refined the idea of legal transplants to be more precise. In this vein, there are both ‘direct’ and ‘indirect’ transplants, as well as ‘cross-pollenizations’, meaning ‘horizontal’ relations between national courts interacting across borders. See Anne-Marie Slaughter, ‘Judicial Globalization’, 40 Va. J. Int’l L. 1103, 1112 (2000); John Bell, ‘Mechanisms for Cross-Fertilisation of Administrative Law in Europe’, in Jack Beatson and Takis Tridimas (eds.), New Directions in European Public Law (1998) 147.

117  See Daniel Berkowitz, Katharina Pistor, and Jean-Francois Richard, ‘The Transplant Effect’, 51 Am. J. Comp. L. 163, 179–81 (2003) (rejecting the theory that colonial origin matters in success of legal institutions and arguing that legal systems are more receptive to transplanted legal norms when the transplant makes a significant adaptation of the foreign formal legal order to initial conditions and is familiar with the borrowing legal system); Jonathan M. Miller, ‘A Typology of Legal Transplants: Using Sociology, Legal History and Argentine Examples to Explain the Transplant Process’, 51 Am. J. Comp. L. 839 (2003) (discussing the successes and failures of legal transplants based on the role of the donor country in the transplant and a model of four typologies: cost-savings, external compulsion, material and political gains for entrepreneurial legal importers, and capacity to increase institutional legitimacy through the prestige of a foreign transplant). ‘Procedural ecology’ is a term borrowed from Mirjan Damaska’s encyclopaedic array of artful metaphors. Damaska, ‘The Uncertain Fate of Evidentiary Transplants’ 840.

118  See George C. Harris, ‘Testimony for Sale—The Law and Ethics of Snitches and Experts’, 28 Pepp. L. Rev. 1, 3 (2000). See also Edward K. Cheng, ‘Same Old, Same Old: Scientific Evidence Past and Present’, 104 Mich. L. Rev. 1387, 1392 (2006).

119  See Cheng, ‘Same Old, Same Old: Scientific Evidence Past and Present’, 1392 (‘That the problems surrounding adversarial experts have stayed with us for over two hundred years should be entirely unremarkable. The methods of presenting expert knowledge are fundamentally the same today as they were in 1783, and the system’s structure breeds these pathologies. If anything, the system’s attributes have gotten worse.’).

120  Robertson, ‘Blind Expertise’, 178 (describing the limited use of court-appointed experts in the US system). See also, Miller, ‘A Typology of Legal Transplants: Using Sociology, Legal History and Argentine Examples to Explain the Transplant Process’, (discussing the success or failure to accept foreign legal institutions, generally); Berkowitz, Pistor, and Richard, ‘The Transplant Effect’, 179–81 (norms must adapt to the receiving country and mesh on a cultural conceptual level).

121  For instance, Professor Langbein proposed radical reforms for US litigation based on the so-called ‘German advantage’. The proposal spawned an avalanche of responses explaining why the US could not adopt these proposed reforms. See, e.g., Bradley Bryan, ‘Justice and Advantage in Civil Procedure: Langbein’s Conception of Comparative Law and Procedural Justice in Question’, 11 Tulsa J. Comp. & Int’l L. 521 (2004) (favourably comparing the German method of civil procedure to the US method through the lenses of the Langbein and Allen articles); Michael Bohlander, ‘The German Advantage Revisited: An Inside View of German Civil Procedure in the Nineties’, 13 Tul. Eur. & Civ. L.F. 25 (1998) (comparing Langbein’s and Allen’s arguments in addition to providing his own insight into the German system); Gregory F. Hauser, ‘Representing Clients from Civil Law Legal Systems in US Litigation: Understanding How Clients from Civil Law Nations View Civil Litigation and Helping Them Understand US Lawsuits’, 17-AUT Int’l L. Practicum 129, 132–3 (2004) (outlining systemic differences between civil and common law litigation); John C. Reitz, ‘Why We Probably Cannot Adopt The German Advantage in Civil Procedure’, 75 Iowa L. Rev. 987 (1990) (criticizing ‘The German Advantage’); Ronald J. Allen Kurt, ‘The German Advantage in Civil Procedure: A Plea for More Details and Fewer Generalities in Comparative Scholarship’, 82 Nw. U. L. Rev. 705 (1988) (concluding that Professor Langbein’s proposals for German law in the US only work at a level of abstraction); John H. Langbein, ‘The German Advantage in Civil Procedure’, 52 U. Chi. L. Rev. 823 (1985).

122  See Serge Lazareff, ‘International Arbitration: Towards a Common Procedural Approach’, in Stefan N. Frommel and Barry A.K. Rider (eds.), Conflicting Legal Cultures in Commercial Arbitration (1999) 31, 31 (noting an increasing awareness among both arbitrators and practitioners of ‘an emerging “harmonised procedural pattern” in international arbitration’); Alan Scott Rau and Edward F. Sherman, ‘Tradition and Innovation in International Arbitration Procedure’, 30 Tex. Int’l L.J. 89, 90–5 (1995); Marianne Roth, ‘False Testimony in International Commercial Arbitration: A Comparative View’, 7 N.Y. Int’l L. Rev. 147, 152 (1994) (‘The trend in international commercial arbitration is to follow a procedure which combines the most desirable features of common and civil law practices.’); Andreas F. Lowenfeld, ‘The Two-Way Mirror: International Arbitration as Comparative Procedure’, 7 Mich. Y.B. Int’l Legal Stud. 163, 163 (1985).

123  See IBA Rules on the Taking of Evidence in International Arbitration (2010), <http://www.ibanet.org/Publications/publications_IBA_guides_and_free_materials.aspx#takingevidence> [IBA Evidence Rules (2010)]; Pedro J. Martinez-Fraga, ‘Good Faith, Bad Faith, but Not Losing Faith: A Commentary on the 2010 IBA Rules on the Taking of Evidence in International Arbitration’, 43 Geo. J. Int’l L. 387, 430–1 (2012) (outlining major advantages and shortcomings of the 2010 IBA Evidence Rules).

124  See Mark Kantor, ‘A Code of Conduct of Party-Appointed Experts in International Arbitration—Can One Be Found?’ 849 PLI/Lit 191, 199–200 (2011). The Milan Chamber rules of international arbitration appear to be the only rules that impose obligations on expert witnesses, but somewhat unhelpfully, they simply state that experts must be ‘neutral’ in the same manner as arbitrators. The Code of Ethics of the Camera Arbitrable of Milan provides in Article 1.2: ‘This Code of Ethics shall apply by analogy to expert witnesses to the arbitral body appointed in the arbitral proceedings administered by the Chamber of Arbitration.’ As explained in more detail later, this provision apparently pertains only to experts who are appointed by the tribunal. See paras 4.61–4.70. Another exception is ICSID Arbitration Rule 35(3), which requires that experts ‘solemnly declare upon [their] honour and conscience that [their] statement[s] will be in accordance with [their] sincere belief[s]’. This requirement applies equally to tribunal- and party-appointed arbitrators.

125  The most thorough examination of the issue to date is by Mark Kantor in his article, ‘A Code of Conduct of Party-Appointed Experts in International Arbitration—Can One Be Found?’. See also Ruth Fenton, ‘A Civil Matter for a Common Expert’. For general discussions on the use of experts in international arbitration, see Pierre A. Karrer, ‘The Civil Law and Common Law Divide: An International Arbitrator Tells It Like He Sees It’, 63-APR Disp. Resol. J. 72 (2006).

126  See Gary B. Born, International Commercial Arbitration (2009) 1861.

127  Born, International Commercial Arbitration 1861.

128  Born, International Commercial Arbitration 1861.

129  IBA Evidence Rules, art. 5(1).

130  IBA Evidence Rules, art. 6(5).

131  See IBA Evidence Rules, arts. 5(4), 8. See also Fabian von Schlabrendorff, ‘Ethical Standards for Arbitrators, Hybrid Proceedings, Rules of Transnational Law: Are We Moving Towards a Uniform Law of International Arbitration?’ 2009 Annals Fac. L. Belgrade Int’l Ed. 90, 103 (2009) (explaining the purpose of the IBA Rules as procedural options for parties and tribunals).

132  See IBA Evidence Rules, Foreword.

133  See, e.g., SIAC Arbitration Rules, arts. 22, 23 (2013); CIETAC Arbitration Rules, art. 42 (2012); ICC Rules of Arbitration, art. 25 (2012); UNCITRAL Arbitration Rules, art. 29 (2010); AAA International Arbitration Rules, art. 22 (2010); JCAA Commercial Arbitration Rules, R. 38 (2008); ICSID Rules of Procedure for Arbitration Proceedings, R. 34–36 (2006); WIPO Arbitration Rules, arts. 54, 55 (2002); LCIA Arbitration Rules, arts. 20, 21 (1998).

134  See CIArb, Practice Guideline 10: Guidelines on the use of Tribunal-Appointed Experts, Legal Advisers and Assessors (2011), <http://www.ciarb.org/information-and-resources/Practice%20Guideline%2010%20June2011.pdf>; CIArb, Protocol for the Use of Party-Appointed Experts in International Arbitration (2007), <http://www.ciarb.org/information-and-resources/The%20use%20of%20party-appointed%20experts.pdf>.

135  See CIETAC Arbitration Rules, art. 42(3) (2012); Justin D’Agostino, ‘Key changes to the CIETAC Arbitration Rules’, Kluwer Arb. Blog, 11 Apr. 2012, <http://kluwerarbitrationblog.com/blog/2012/04/11/key-changes-to-the-cietac-arbitration-rules/>.

136  See ICC Rules for Expertise (2003).

137  See Nils Schmidt-Ahrendts, ‘Expert Teaming—Bridging the Divide between Party-Appointed and Tribunal-Appointed Experts’, 43 Victoria U. Wellington L. Rev. 653 (2012); Klaus Sachs and Nils Schmidt-Ahrendts, ‘Protocol on Expert Teaming: A New Approach to Expert Evidence’, in Albert Jan van den Berg (ed.), Arbitration Advocacy in Changing Times (15 ICCA Congress Series, 2010, Kluwer 2011) 135, 145; J. Martin Hunter, ‘“Experts” in International Arbitration’, Kluwer Arb. Blog, 7 Feb. 2011, <http://kluwerarbitrationblog.com/blog/2011/02/07/experts-in-international-arbitration/>.

138  See Sachs and Schmidt-Ahrendts, ‘Protocol on Expert Teaming’, 145; J. Martin Hunter, ‘“Experts” in International Arbitration’, Kluwer Arb. Blog, 7 Feb. 2011, <http://kluwerarbitrationblog.com/blog/2011/02/07/experts-in-international-arbitration/>.

139  See Foster, Science and the Precautionary Principle in International Courts and Tribunals 114.

140  See, e.g., Caratube Int’l Oil Co. LLP v Kazakhstan, ICSID Case No. ARB/08/12, Award (5 Jun. 2012), para. 72; Libananco Holdings Co. Ltd. v Turkey, ICSID Case No. ARB/06/8, Award (2 Sep. 2011), para. 50 (using witness conferencing under IBA rules and CIArb rules). See also Foster, Science and the Precautionary Principle in International Courts and Tribunals 123–44 (‘[I]n 2009 [expert conferencing] was described as the normal method for examining experts [in international arbitral proceedings] and greater use of the same procedure for taking evidence from non-expert witnesses of fact was being encouraged.’); Michael Hwang, ‘Witness Conferencing and Party Autonomy’, 7(1) Transnat’l Disp. Mgmt. 19 (2010), <http://www.transnational-dispute-management.com.ezaccess.libraries.psu.edu/search/browse.asp?v0_0=%22Witness+Conferencing+and+Party+Autonomy%228v1_0=pdf_text8v2_0=50>.

141  ‘The process of selecting, educating and paying a party-appointed expert creates an environment that inherently puts pressure on the expert’s independence.’ Kantor, ‘A Code of Conduct of Party-Appointed Experts in International Arbitration—Can One Be Found?’ See also George C. Harris, ‘Testimony for Sale – The Law and Ethics of Snitches and Experts’, 28 Pepp. L. Rev. 1, 3 (2000) (‘Despite the obvious incentives for perjury and tailored testimony, [the] justice system accepts payments to [expert] witnesses… as justifiable and necessary.’).

142  IBA Evidence Rules, art. 5.2(a) (2010).

143  IBA Evidence Rules, art. 6.3. Notably, the IBA Rules also provide that the expert report any non-compliance by a Party with an appropriate request and its effects on determination of an issue, presumably so that the tribunal cannot only take non-compliance into account in assessing the issue, but potentially also when assessing costs or other sanctions for non-compliance. For further discussion of this issue with regard to the sanction power of tribunals, see Chapter 6.

144  IBA Evidence Rules, arts. 5.2(c) (party-appointed experts) and 6.2 (tribunal-appointed experts).

145  The inherent ambiguity of ‘independence’ as applied to experts is discussed in the next section. This ambiguity is particularly troubling since a tribunal-appointed expert may decide, even in good faith, that previous repeat appointments by a law firm would not interfere with an ability to render independent expert evidence in a new case. That assessment, however, might not be readily acceptable to an opposing party (or the tribunal) were it disclosed in advance.

146  See, e.g., Robertson, ‘Blind Expertise’, 190–4; Daylian M. Cain et al., ‘The Dirt on Coming Clean: Perverse Effects of Disclosing Conflicts of Interest’, 34 J. Legal Stud. 1 (2005).

148  Robertson, ‘Blind Expertise’, 190.

149  See IBA Evidence Rules, art. 5 (2)(c) (party-selected experts) and art. 6(2) (tribunal-appointed experts).

150  See Chartered Institute of Arbitrators, Protocol for the Use of Party-Appointed Expert Witnesses in International Arbitration, art. 4(1).

151  See, e.g., London Ct. of Int’l Arb. Arbitral Rules, art. 5.2 (‘All arbitrators conducting an arbitration under these Rules shall be and remain at all times impartial and independent of the parties; and none shall act in the arbitration as advocates for any party.’).

152  As described in earlier chapters, historically, the normal US domestic practice was to have highly partisan party-appointed arbitrators, who met and communicated regularly with the parties and counsel who appointed them. See, e.g., Sunkist Soft Drinks, Inc. v Sunkist Growers, Inc., 10 F.3d 753, 759 (11th Cir. 1993) (finding no prejudicial misconduct despite finding that party-arbitrator met with representatives and witnesses of appointing party before arbitration to plan strategy).

153  See, e.g., Rios v Tri-State Ins. Co., 714 So. 2d 547, 549 (Fla. Dist. Ct. App. 1998) (allowing unilateral contingent fee arrangement between party and party-appointed appraiser/arbitrator when the arbitration contract stated ‘[e]ach appraiser shall be paid by the party selecting that appraiser’); Hozlock v Donegal Companies/Donegal Mut. Ins. Co., 745 A.2d 1261, 1262 (Pa. Super. Ct. 2000) (same). See also AAA/ABA, Code of Ethics for Arbitrators in Comm’l Disps., Cannon III(B)(3) (2004), <http://www.adr.org/si.asp?id=4582> (‘[E]ach party-appointed arbitrator may consult with the party who appointed the arbitrator concerning arrangements for any compensation to be paid to the party-appointed arbitrator. Submission of routine written requests for payment of compensation and expenses in accordance with such arrangements and written communications pertaining solely to such requests need not be sent to the other party.’).

154  See Sphere Drake Ins. Ltd. v All Am. Life Ins. Co., 307 F.3d 617, 620 (7th Cir. 2002) (‘[I]n the main party-appointed arbitrators are supposed to be advocates.’); United Transp. Union v Gateway W. Ry. Co., 284 F.3d 710, 711 (7th Cir. 2002) (‘[T]he party members of the panel are expected to vote in accordance with their principals’ wishes[.]’).

155  See AAA/ABA, Code of Ethics for Arbitrators in Comm’l Disps., Canon III.B (2004).

156  For example, when scholars talk about independence in relation to expert witnesses, they say that an expert has an obligation ‘to approach every question with independence and objectivity’. Steven Lubet, ‘Expert Witnesses: Ethics and Professionalism’, 12 Geo. J. Legal Ethics 465, 467 (1999).

157  The term ‘independent’ is used when there are ‘relationships between an arbitrator and one of the parties, or with somebody closely connected with one of the parties’. IBA, Rules of Ethics for Int’l Arbitrators, art. 3.1 (1987). The ‘relationships’ that might interfere with an arbitrators ‘independence’ include if an arbitrator were paid by only one party, or engaged in ex parte communications with a party regarding their case strategy.

158  See Murat Ozsunay, ‘Turkish National Report’, in Storme et al, Civil Procedure in Cross-Cultural Dialogue 316, 323 (citing Turkish Code of Civil Procedure, No. 6100, Official Gazette 04.02.2011, No. 27836 (2011); Turkish Code of Criminal Procedure, No. 5271, Official Gazette: 17.12.2004, No. 25673 (2004)).

159  Kantor, ‘A Code of Conduct of Party-Appointed Experts in International Arbitration—Can One Be Found?’ 201 (‘The format of the oath or affirmation often administered in US domestic arbitrations (“Do you swear to tell the truth, the whole truth and nothing but the truth”) arguably establishes a complete range of ethical duties for all witnesses, enforceable by the prospect of a criminal or civil perjury claim when breached.’).

160  Many countries, such as Sweden, do not permit arbitrators to swear witnesses. See W. Laurence Craig et al., International Chamber of Commerce Arbitration, 2nd edn., (1990) § 25.01.

161  In this respect, expert opinions are often determined to be not credible. The problems are that there is no sanction (other than reputation) for rendering an opinion that is not credible and it is costly for the decision-maker to determine that an expert opinion is not credible.

162  Of course, in testifying, experts also may make statements of fact, which can be true or false. Moreover, an opinion rendered in a proceeding that was not sincere and was contrary to an expert’s actual belief at the time of testimony would come close to false opinion, but such subjective proof is usually difficult to come by.

164  See A. J. van den Berg (ed.), International Commercial Arbitration: Important Contemporary Questions (2003) 283–84 (discussing perjury laws and their application to arbitration proceedings in England, Switzerland, Austria, and the United States); Roth, ‘False Testimony in International Commercial Arbitration’, 149–50. This apparent tolerance is most likely linked to the notion that in many civil law systems, oral witness testimony is not a primary source of evidence. In fact, many systems effectively presume disingenuous testimony from parties or persons with a potential interest in the outcome and thus preclude them from testifying altogether. See Damaska, ‘The Uncertain Fate of Evidentiary Transplants’, 842–43 (‘In most continental jurisdictions, a litigant’s statement is not a recognized means of proof of his allegations. In others, judges are expected to order formal interrogations of a party only as a means of last resort—if other evidence appears insufficient.’).

165  See Roth, ‘False Testimony in International Commercial Arbitration’ 156–9 (English laws against perjury do not extend to international arbitration, but Swiss laws do).

166  See Gulf Petro Trading Co. v Nigerian Nat. Petroleum Corp., 512 F.3d 742 (5th Cir. 2008).

167  See Richard M. Mosk, ‘Attorney Ethics in International Arbitration’, 5 Berkeley J. Int’l L. Publicist 32, 33 (2010).

168  Sanders, ‘Expert Witness Ethics’, 1541.

169  Sanders, ‘Expert Witness Ethics’, 1541.

170  In addition to being difficult to prosecute for perjury, expert witnesses generally enjoy immunity for their testimony and submissions in court. See Andrew Jurs, ‘The Rationale for Expert Witness Immunity or Liability Exposure and Case Law Since Briscoe: Reasserting Immunity Protection for Friendly Expert Witnesses’, 38 U. Mem. L. Rev. 49, 51–2 (2007). See also Randall K. Hanson, ‘Witness Immunity Under Attack: Disarming “Hired Guns”’, 31 Wake Forest L. Rev. 497, 497–8 (1996). There are a few potential exceptions when expert testimony involves the collateral exercise of expert duties other than that of the witness, which may be subject to general malpractice standards. There have also been some cases in which a party’s own expert has been held liable for malpractice for changing testimony. See, e.g., Michael T. Nelson, ‘Pace v Swerdlow: Can Expert Witnesses Face Liability for Changing Their Minds? The Tenth Circuit Weighs in on the Element of Proximate Cause in A Claim of Expert Negligence’, 86 Denv. U. L. Rev. 1199 (2009).

171  See John Macdonell, ‘Galileo’, in Historical Trials (1927) 109, 117–8 (reproducing in respect to the first trial of Galileo the Assessor’s testimony that Galileo’s central premises were not believable, but actually heretical). It is noteworthy that no one involved in Galileo’s trial disputed the truth of the geocentric theory in court, not even Galileo. At the time, the geocentric theory was considered a fact, and belief had nothing to do with it. For instance, a letter written by Bellarmine was cited by Galileo in his own defence against the specific injunction during the trial as key evidence. The letter stated, inter alia: ‘Only the declaration made by the Holy Father and published by the Sacred Congregation of the Index has been revealed to [Galileo], which states that the doctrine of Copernicus, that the earth moves around the sun and that the sun is stationary in the center of the universe and does not move east to west, is contrary to the Holy Scripture and therefore cannot be defended or held.’ Richard J. Blackwell, Behind the Scenes at Galileo’s Trial (2006) 9, 3–27. See also Foster, Science and the Precautionary Principle in International Courts and Tribunals 10 (discussing how science is socially and legally constructed and that all scientific assertions may be discarded).

172  See 18 USC.A. §§ 1621, 1623. See also US Dept. of Justice, United States Attorneys’ Manual: Title 9: Criminal Resource Manual (1997), 1744–8, <http://www.justice.gov/usao/eousa/foia_reading_room/usam/title9/69mcrm.htm#9-69.200>.

173  This excellent example comes from some of the top thinkers in this field in the US. As Joseph Sanders explains: ‘Even correct beliefs without appropriate justification are not knowledge. The gambler’s fallacy provides an example. When playing roulette, the gambler observes that his favourite number has not come up for a very long time. He believes it is “due” and bets on it. He wins. He was right in his belief about the number coming up, but for the wrong reasons. [The gambler]… may say: “I just knew it would win.” But [he] didn’t really know. [He] was convinced and [he] turned out to be right. That is all.’ Sanders, ‘Expert Witness Ethics’ 1541 (internal citations omitted) (citing and quoting Michael Williams, Problems of Knowledge: A Critical Introduction to Epistemology (2001) 16–9).

174  The standard is named for the case in which the test was announced: Daubert v Merrell Dow Pharm., 509 US 579 (1993).

175  The analogy of a panda’s mock ‘thumb’ to civil procedure innovations was introduced by E. Donald Elliott, ‘Managerial Judging and the Evolution of Procedure’, 53 U. Chi. L. Rev. 306, 307 (1986) (citing Stephen Jay Gould, The Panda’s Thumb: More Reflections in Natural History (1980) 21–24 for the metaphor).

176  Although Elliott made this observation about innovations in US judicial procedures, it is especially pertinent with respect to recent procedural innovations regarding expert witnesses in international arbitration.

177  See Email from Tore Wiwen-Nilsson (7 Feb. 2006) (on file with author); CME Czech Republic B.V. v The Czech Republic, UNCITRAL (The Netherlands/Czech Republic BIT) (13 Sept. 2001) (dissenting opinion of the Arbitrator JUDr Jaroslav Hándl against the Partial Arbitration Award), <http://italaw.com/alphabetical_list_content.htm> (‘[T]he witnesses should be heard as witnesses of the facts … [T]his principle was not observed [by the arbitrator] who permitted to the witnesses nominated by the Claimant to present their opinions to individual legal questions, e.g., as a witness was heard the attorney at law of the Claimant, who presented his legal opinions.’).

178  One exception is when foreign law applies. For example, in the United States, under Federal Rule of Civil Procedure 44.1, foreign law is introduced through expert testimony. See also Suzannah Linton and Dr Firew Kebede Tiba, ‘The International Judge in an Age of Multiple International Courts and Tribunals’, 9 Chi. J. Int’l L. 407, 424 (2009) (advocating the use of legal experts in international proceedings).

179  See J-G Castel, ‘Proof of Foreign Law’, 22 U. Toronto L.J. 33, 36–7 (1972).

180  See Christoph Schreuer, The ICSID Convention: A Commentary (2001) 661; Société Ouest-Africaine des Bétons Industriels (SOABI) v La République du Sénégal, ICSID Case No. ARB/82/1, Award, ¶ 9.17 (25 Feb. 1988), 2 ICSID Reports 368–9 (1988).

181  Société Ouest-Africaine des Bétons Industriels (SOABI) v La République du Sénégal, ¶ 9.16.

182  For an analysis of this development in judicial contexts, see Sanders, ‘Expert Witness Ethics’, 1580 (remarking on the failure of the Court Appointed Scientific Expert (CASE) programme in the US).

184  Thomas D. Lyon, ‘Child Witnesses and the Oath: Empirical Evidence’, 73 S. Cal. L. Rev. 1017, 1064 (2000). See also Hugo Munsterberg, On the Witness Stand: Essays on Psychology and Crime (1912) 48. Hugo notes that early in this century Munsterberg offered strong, but mixed opinions on the value of oaths. On the one hand, Munsterberg opined that an oath ‘can and will remove to a high degree the intention to hide the truth’, but on the other hand, noting that witnesses can be inaccurate for reasons other than dishonesty, ‘it may be an open question to what degree [the oath] can increase the objective truthfulness’.

185  Varda Liberman et al., ‘The Name of the Game: Predictive Power of Reputations versus Situational Labels in Determining Prisoner’s Dilemma Game Moves’, 30 Pers. & Soc. Psychol. Bull 1175 (2004).

186  Douglas Kenrick et al., Social Psychology: Goals in Interaction, 5th edn., (2010) 451.

187  John M. Darley and C. Daniel Batson, ‘“From Jerusalem to Jericho”: A Study of Situational and Dispositional Variables in Helping Behavior’, 27 J. Pers. & Soc. Psychol. 100 (1973). For these references, I am truly grateful for guidance from one of the leading experts on experts—Professor Michael Saks.

188  See Federal Courts Rules, SOR/98-106, R. 52.2, Form 52.2, sched. (2013) (Can.), <http://canlii.ca/en/ca/laws/regu/sor-98-106/latest/sor-98-106.html#history>; Rules Amending the Federal Courts Rules (Expert Witnesses), 143 Can. Gazette (17 Oct. 2009), <http://www.gazette.gc.ca/rp-pr/p1/2009/2009-10-17/html/reg1-eng.html>; Uniform Civil Procedure Rules 2005, R. 31.23 (NSW), <http://www.legislation.nsw.gov.au/viewtop/inforce/subordleg+418+2005+FIRST+0+N/>: ‘(3) Unless the court otherwise orders, an expert’s report may not be admitted in evidence unless the report contains an acknowledgment by the expert witness by whom it was prepared that he or she has read the code of conduct and agrees to be bound by it. (4) Unless the court otherwise orders, oral evidence may not be received from an expert witness unless the court is satisfied that the expert witness has acknowledged, whether in an expert’s report prepared in relation to the proceedings or otherwise in relation to the proceedings, that he or she has read the code of conduct and agrees to be bound by it.’

189  See Hilmar Raeschke-Kessler, ‘Witness Conferencing’, in The Leading Arbitrators’ Guide to International Arbitration, 2nd edn. (2008) 418–19.

190  See Jeff Waincymer, Procedure and Evidence in International Arbitration (Kluwer, 2012) 968–69, § 12.14.11; Wolfgang Peter, ‘Witness “Conferencing”’, 18 Arb. Int’l 47 (2002) (‘As a matter of fact, it is very difficult for a witness under the gaze of their counterparts to persist in a clearly inaccurate version of the facts. It is also very difficult to stick to a well-prepared but highly subjective line of factual presentation.’).

191  See Born, International Arbitration 170 (‘[W]itness-conferencing seldom genuinely saves time. On the contrary, witness-conferencing can take more time, because it is often best used in addition to, rather than instead of, traditional cross-examination. This enables cross-examination to identify key areas of disagreement, which can then be focused in a witness conference.’); see also J. Martin Hunter, ‘Expert Conferencing and New Methods’, in Albert Jan van den Berg (ed.), International Arbitration 2006: Back to Basics? (13 ICCA Congress Series 2006, Kluwer, 2007); Doug Jones, ‘Party Appointed Experts: Can They be Usefully Independent?’ 8(1) Transnat’l Disp. Mgmt. 1, 10–11 (2011); Yuka Fukunaga, ‘Chapter 5: Experts in WTO and Investment Litigation’, in Jorge A. Huerta-Goldman, Antoine Romanetti et al. (eds.), 43 WTO Litigation, Investment Arbitration, and Commercial Arbitration, Global Trade Law Series (Kluwer, 2013) 135, 158; Harris Bor, ‘Chapter 24: Expert Evidence’, in Julian D.M. Lew, Harris Bor, et al. (eds.), Arbitration in England, with chapters on Scotland and Ireland (Kluwer, 2013) 503, 508–09.

192  Antonio Hierro, ‘Reducing Time and Costs in ICC International Arbitration Excess Time and Costs of Arbitration: An Incurable Disease?’ 2012 Spain Arb. Rev. 37, 45 (2012) (arguing witness-conferencing works best when experts come from similar cultures and backgrounds and are not too directly involved as part of the ‘team’ for the case).