Burden of Proof in Investment Treaty Arbitration: Shifting?

Abstract

The issue of the burden of proof is deemed to be a fundamental principle required for a fair trial. Its essence is encapsulated in the so-called onus probandi principle pursuant to which the party making an allegation bears the burden of proving it. The present paper offers a brief analysis of the allocation of the burden of proof in investment treaty arbitration. The focus is primarily on the jurisprudence concerning the state of necessity in Argentina as well as the national treatment standard under Article 1102 NAFTA. Its central question is whether the onus probandi rule, under the present institutional framework for the adjudication of investment disputes, does actually offer a workable instrument towards the proper administration of justice.