7 Good-Faith Standards for Evidence

Subject(s):

Witnesses — Good faith — General principles of international law — Arbitrators — Expert evidence

This chapter examines how investment tribunals apply the principle of good faith to justify their discretion in taking evidentiary decisions. It first considers the discretion given to arbitrators to determine aspects of evidence, including its relationship to the general idea of a fair trial, before discussing the domestic rules on taking and submitting evidence in international investment arbitration as well as the international rules and requirements for evidence applied by arbitral tribunals. Three relevant cases that tackle the question of what is the threshold requirement for collection and submission of evidence in good faith are then reviewed: Methanex v United States, EDF v Romania, and Renee Rose Levy and Gremcitel v Peru. The chapter goes on to analyse the good faith requirements for experts and witnesses and concludes by explaining the gap-filling role played by the principle of good faith to uphold and expand due process in investment arbitration.