Tribunal duties and the exclusion of evidence in international arbitration: the tug-of-war of fairness and efficiency

Abstract Arbitral procedure aims to strike the right balance between fairness and efficiency in the specific and unique circumstances of the case. However, in some difficult cases, both considerations can pull in opposite directions. The exclusion of evidence provides a particularly apt example in which the dilemma arises, aggravated by the considerable evidentiary discretion vested in tribunals and the overall lack of guidance in applicable laws and rules on approaching such circumstances. This article argues that the tug-of-war between fairness and efficiency in the context of the exclusion of evidence can be resolved with the help of relevant tribunal duties, which should guide the exercise of tribunal discretion. These include the duty (i) to resolve the dispute; (ii) to observe due process; (iii) to conduct the procedure efficiently and effectively; (iv) to act with impartiality and independence; and (v) to render an award that is enforceable/not subject to set aside.