Most international arbitration proceedings require expert evidence from accountants, economists, scientists, but also from legal experts. That is particularly true when the matter at hand raises complex issues in highly specialised areas of the law (art law, derivatives law, etc.) or questions of foreign law (with globalisation, contractual disputes may for instance raise issues of Brazilian or Chinese law, i.e. legal regimes whose intricacies may not necessarily be well known from the arbitrators and the parties). When arbitral proceedings raise such issues, the parties will generally retain law professors, retired judges or other prominent lawyers to assist the tribunal.
As I have been regularly asked over the years to testify as a legal expert in the areas of competition and intellectual property law, i.e. the fields of law I teach and practice, I have often asked myself and the law firms which retained me what it takes to be an effective expert witness over issues of law. While every case is different and arbitration specialists may have different views as to what an effective expert witness is, I have come to the view that the following features are important.
First, the expert witness obviously needs to have relevant knowledge of the issues that will be presented to her. Moreover, the positions that she may have taken in the past (for instance, in law review articles, in judgments, etc.) should generally be consistent with the positions that she intends to take in her expert witness report. While one’s opinions over legal matters may vary over time and every case is different, it would not be credible for a legal expert to take positions that are diametrically opposed to those one held in the past. It is better to reject an expert witness assignment at the outset that having subsequently to conceal tensions between positions helpful to the client and positions adopted in the past. While an expert must be independent, she needs to be generally aligned with the positions held by the party that has retained her. Otherwise, the expert will either not to be true to herself or to provide a disservice to the client.
Second, while legal expert witnesses are deemed to deal with issues of law rather than issues of fact, a legal expert cannot abstract away from the facts (even if she, as a legal expert, should obviously not opine on facts). For instance, a relevant issue in most competition cases relates to market definition, which is an intensely factual matter. It would be wrong for an expert witness to take at face value the market definition suggested by the parties which retained her without taking the trouble of checking, by asking pertinent questions, whether the market in question is correctly defined from a competition law standpoint. Otherwise, she runs the risk that the entirety of her expert opinion may be vitiated because it is built on false premises. Moreover, there may be circumstances where certain facts that are presented by the parties as a basis for a claim of competition law infringement may appear inconsistent with the basic understandings of economic thinking. How is it, for instance, possible that the party in question claims that it has no market power while it has been able to increase its prices and profit margins over the years? This expert thus needs to verify with the party which has retained her whether the facts as presented to her are consistent. In a discipline like competition law, where facts are extremely important, one cannot be a serious expert witness by focusing only on an abstract legal question, except if it is possible to isolate this question from the facts of the case because it is of a theoretical nature.
Third, while a legal expert witness should be independent and not act like one of the lawyers of the party that selected her, she needs to be ready to defend the position of that party while remaining true to her principles and the law. In other words, when an expert is offered an expert assignment by one of the parties to an arbitration, she needs to enquire as to the position that the party intends her to take in her expert witness statement and make sure she is comfortable defending it. While the duty of an expert is to assist the arbitral tribunal, it would be foolish to think that an expert can be remunerated by one of the parties to suddenly take positions that are hostile to that party (considering, of course, that an expert cannot lie in her expert witness report or in her cross-examination). If an expert does not feel comfortable with the position pursued by the party wishing to retain her, she should simply decline the offer. Proceeding otherwise is dishonest and may not end up well.
Fourth, in most cases, the legal expert will not be the only expert involved. For instance, in competition or intellectual property cases, economic, technical and industry experts are also regularly invited to testify. When that is the case, it is important for the legal expert to coordinate her work, usually through the law firm acting for the party that has retained her, with the other experts in order to ensure the consistency of the positions taken. For instance, in competition cases, it does not make sense for the legal and the economic expert to operate separately and hope that their expert reports will eventually converge on issues such as market definition and dominance. When such issues are at stake, the economic report should feed the legal report. This means that these experts will have to show flexibility needed to work with others, while remaining true to their discipline and principles.
Fifth, experts need to make sure that the propositions contained in their expert report will resist cross-examination as it is a brutal process for which many eminent lawyers, such as law professors or retired judges, may not be necessarily well prepared. Once again, this means that an expert must be comfortable with the positions held by the party that retains her. While the writing of an expert report may allow the expert to conceal some possible discomfort with the positions of the party that has retained her, such discomfort will be exposed in cross-examination. Moreover, however eminent the expert is, she would be ready to go through the humbling experience of cross-examination.
Finally, and perhaps most importantly, legal experts need to take a pedagogical approach in their expert report and cross-examination as the arbitrators, however experienced they are, will often have little knowledge of the intricacies of the areas of law on which the expert will opine. Obscure expert reports full of jargon and technicalities will often be of little assistance to the arbitral tribunal. Thus, eminent lawyers retained as experts must consider that their audience will be composed of very skilled lawyers (the arbitrators), but who generally are laypeople when it comes to the area of law they have been asked to opine on.
In sum, legal experts accepting to testify on behalf of a party to an arbitral proceeding must realise that this is a serious endeavour and must do some due diligence from the outset on what is expected from her and whether the party or its lawyers’ expectations are in line with her own views and principles, and that she can meet them without moving (too far) away from her comfort zone.