Jus Cogens Erga Omnes Revisited: Deconstructing the Normative Hierarchy of Peremptory Norms Under Contemporary Customary International Law

Abstract

The conceptual architecture underpinning jus cogens norms has long been predicated upon a presumed hierarchical supremacy within the international legal order, yet recent state practice and adjudicative developments before the International Court of Justice and ad hoc arbitral tribunals have exposed foundational tensions in this orthodoxy. This article critically interrogates the doctrinal premises upon which peremptory norm status is conferred, examining the evidentiary threshold for norm identification, the contested relationship between jus cogens and erga omnes obligations, and the procedural consequences of norm derogation for treaty invalidity under the Vienna Convention on the Law of Treaties. Employing a systematic doctrinal analysis augmented by jurisprudential mapping across multilateral treaty regimes, this study argues that the prevailing normative hierarchy constitutes an undertheorized construct requiring structural reconceptualization to reflect evolving multilateral consensus and the fragmentation of international legal authority.