Originally from Expert Evidence: Conflicting Assumptions and How to Handle Them in Arbitration - ASA Special Series No. 46

1.    Introduction

The topic of the 2018 ASA Annual Conference was “The Use of Experts in International Arbitration – Conflicting Assumptions and Expectations”. The purpose of the conference was to explore various aspects relating to the presentation of expert evidence and specifically address the issue of conflicting assumptions and expectations that parties may have and how an arbitral tribunal could deal with them.

My task was to deal with specific issues relating to legal experts.

As many arbitration practitioners will have experienced, parties from different cultural and legal backgrounds may indeed have different ideas of the use and purpose of legal experts in international arbitration.

This article is structured in three parts as follows:

•   Different ways of presenting the law before courts (I. below)

•   Legal expert testimony in international arbitration (II. below)

•   Recommendations (III. below)

2.      Different ways of presenting the law before courts

              Before exploring the use of legal expert testimony in international arbitration, it is useful to step back and look at how legal issues are commonly presented before courts. In essence, it seems that two different approaches or traditions exist as set out below.

              2.1.        (Foreign) law as a factual issue

In some jurisdictions the court has a duty to apply the domestic law (the lex fori) ex officio and thus a duty to decide the law itself independent of the parties’ submissions (da mihi facta, dabo tibi jus). Yet, if the law of these jurisdictions requires the court to apply foreign law to the merits, that foreign law is treated as a factual issue that the parties must prove through appropriate means.