The role and function of the principle iura novit arbiter is contested and controversial in international arbitration. Whereas courts in civil law jurisdictions accept this principle more broadly, courts in common law jurisdictions are less willing to accept its existence in international arbitration. This chapter reviews the existing legal position in the United Kingdom (with focus on England and Wales) and argues that the broad powers of arbitral tribunals as provided for in sections 33(1)(b) and 34(2)(g) of the English Arbitration Act (1996) are better viewed as important efficiency drivers in the case management of arbitral proceedings and are less to be viewed as aspects of a “truth finding” exercise to be performed by arbitrators. Even if arbitrators find an independent line of inquiry in a case they are adjudicating, they must present this thinking to the parties, as failing to do so, would typically result in the setting aside of the award under section 68(2)(a) EAA.
The issue of the applicability of the principle iura novit curia or iura novit arbiter (to be precise) in international commercial arbitration is contested in practice. The approach in civil law and common law jurisdictions diverges, making any of the two paradigms as the model for international commercial arbitration unsuitable.