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| 4 minutes read

Hired Gun or Guide to Enlightenment?

The provision of expert witness evidence can be frustrating to a tribunal where the parties take an adversarial view to cross-examination that does nothing to advance the tribunal’s understanding of the differences in opinion between experts. As a result of this, it is becoming increasingly common to see tribunals issuing procedural orders at the outset, requiring the early engagement of experts and the provision of phased joint statements before, and even during, the hearing stage. During the hearing stage, there is now greater reliance on listening to expert witness evidence from two or more experts concurrently, otherwise known as ‘hot tubbing,’ now more and more frequently, the questioning of the experts is mostly led by the tribunal directly rather than the parties’ counsel. These trends provide increased efficiency in the understanding of the expert evidence before and during the hearing, which is becoming progressively important as projects and project data become more complex, yet the average hearing durations are getting shorter.

It may seem strange therefore, that tribunals are increasingly giving expert witnesses more freedom and control in the process, but a considerable number of arbitration practitioners apparently consider that these same party-appointed experts are essentially “hired guns” or “advocates in disguise,” as recorded by 51% of the respondents in BCLP’s Annual Arbitration Survey 2021.

Is there a contradiction here? Should experts that are perceived to be biased, be given more freedom and control in the process?

While there is a noticeable trend towards it, early engagement of experts is not the norm currently, as the perceived lack of control by the parties over the independent expert process often holds back instructing experts early. In the preliminary stages of an arbitration, evidence is still in the process of being collated and the parties’ respective cases are often still being developed and understood. This being the case, parties often have a different strategic need at this stage, in the form of an expert advisor or claims consultant to help develop the claim and there is a sense that appointing an expert witness at this stage would be superfluous. There are, nonetheless, benefits of engaging experts early.

The timing of the instruction is of course important, and those instructing experts need to be mindful that if experts are instructed prior to all the evidence being available, for example, then there is the possibility that opinions may subsequently change. A good expert would identify these risks at the outset, as well as identify the information required to finalize any assessment.

An expert witness who is engaged early on, likely in an independent expert advisor capacity first, provides a direct benefit in assisting a party to understand their true position prior to pleading their case. Having this independent and objective view early in the process allows a party to make informed investment decisions in respect of how the claims should be advanced and often results in better particularized and supported claims. It also enables the experts and parties to identify the evidence required to support the claims made, resulting in a more efficient disclosure process. These factors should result in material gains in terms of time and cost overall.

It is now becoming increasingly common that procedural orders require the experts to meet early in the process to seek agreement on such matters as the scope of their instructions, the documents that they intend to rely on, the methodology to be adopted, and generally any parameters that provide consistency between the expert evidence. Of course, the experts may have legitimate and valid reasons to prefer one method of analysis over another, but if the methodology and the relevant datasets can be agreed upon, any differences between the experts are likely to arise due to substantive differences in expert opinion, as opposed to the fact that the experts had different information available to them, for example. Consequently, the tribunal can have greater confidence and clarity on what the substantive differences of opinion are and focus their attention accordingly.

Providing the experts with a forum to agree to these foundational aspects of their analysis early in the process, before their opinions become too entrenched, is likely to increase the level of agreement and further improve efficiency.   

During the hearing stage, tribunals often encourage the experts to continue to meet to seek agreement and narrow the issues between them. Tribunals are often receptive to additional joint statements at this late stage, providing the parties agree and valuable progress is being made in terms of a further agreement between the experts. This approach is often coupled with the hot tubbing of the experts. Generally, though not always, the hot-tubbing process is led by the tribunal. Often the experts are required to provide a brief presentation summarizing their opinion and explaining the reasons for any differences in opinion. The tribunal can then ask the experts questions on the material issues, as they see them. Hearing both experts in this way, at the same time, on the same issues, can be a very effective and efficient way for the tribunal to fully understand the reasons for any differences of opinion between the experts.  

In conclusion, good experts who are suitably experienced and remain independent throughout can be efficient and effective in giving the tribunal the guidance it needs, whether the procedural orders permit early engagement or not. With light guidance from the tribunal, allowing experienced experts some control over the process, consistent of course with their instructions, can help drive an efficient process. Conversely, however, less experienced experts who promote partisan views, play tactical games or who are unseasoned can frustrate a perfectly ordered process, impacting efficiency and increasing the complexity that a tribunal wishes to avoid. Thus, it is the conduct and experience of the experts, rather than the directed procedural process that has the most impact on the efficacy of the expert evidence. So, choose your experts wisely.

David Dellar is a Managing Director of Ankura based in Dubai and an internationally recognized delay expert.

Michael Stokes is a Senior Managing Director of Ankura based in London and an internationally recognized quantum expert.

This article was first published for the Jus Mundi Construction Arbitration Report.

© Copyright 2023. The views expressed herein are those of the author(s) and not necessarily the views of Ankura Consulting Group, LLC., its management, its subsidiaries, its affiliates, or its other professionals. Ankura is not a law firm and cannot provide legal advice.


emea, uk, article, construction disputes, construction & infrastructure, international arbitration

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