Investment Arbitration Counsel’s Role in the Progressive Development of International Law

Abstract

Starting from the observation that international law remains largely perceived today as a state-centric product, this chapter argues that private actors and their respective counsel have a sizeable effect on the progressive development of international law. International jurisprudence—which is itself a subsidiary source of international law—is contingent on how counsel assist tribunals in reaching well-researched and well-reasoned decisions, which eventually contribute to the development of a more reliable jurisprudence constante. In the realm of investment treaty arbitration, counsel have a role to play in assisting tribunals when it comes to treaty interpretation or the identification of rules of customary international law and general principles of law. Counsel might do so in a variety of ways, including by providing arbitral tribunals with relevant evidence to interpret the specific meaning behind a treaty provision, scrutinizing relevant state practice to identify a rule of customary international law, or conducting the necessary comparative work of divining the existence of a general principle of law in a variety of legal traditions. This chapter reviews some investment treaty cases where counsel have distinguished themselves in this regard.