This chapter addresses the role of international organisations in the formation of customary international law from a specific viewpoint: whether international organisations, which knowingly have many instruments to shape the behaviour of States, are also capable of shaping the opinio juris of States. For instance, would an international organisation such as the United Nations be able to promote, or at least influence the formation of opinio juris that is consistent with findings and recommendations of the Intergovernmental Panel on Climate Change? To develop my argument, I organise the chapter in two main parts – a study into the concept of opinio juris, and a study into the ability of international organisations to promote opinio juris with a desired content. This work concludes by playing down the possibility that international organisations are able to coordinate international processes in a manner to shape opinio juris pursuant to desired standards.
This collection of chapters provides the most comprehensive study of the theory and practice on the contribution of international organisations and non-State actors to the formation of customary international law. It offers new practical and theoretical perspectives on one of the most complex questions about the making of international law, namely the possibility that actors other than states contribute to the making of customary international law. Notwithstanding the completion by the International Law Commission of its work on the identification of customary international law, the making of customary international law remains riddled with acute practical and theoretical controversies which have been left unresolved and which continue to be intensively debated in both practice and scholarship. Making extensively reference to the case-law of international law courts and tribunals as well as the practice of treaty-monitoring bodies while also engaging with the most recent scholarly work on customary international law, this new volume provides innovative tools and guidance to legal scholars, researchers in law, law students, lecturers in law, practitioners, legal advisers, judges, arbitrators, and counsels as well as tools to address contemporary questions of international law-making.
Stories about international organisations, non-State actors, and the formation of customary international law
Sufyan Droubi and Jean d’Aspremont
This chapter shows that the dominant approach to custom-forming has remained adverse to the idea that international organizations and non-State actors contribute to the formation of customary international law. This orthodoxy promotes an image of these actors with which we, and the subsequent contributors to this volume, engage. From the perspective of the dominant approach, international organizations are often understood as having very restricted formal participation in the formation of customary international law. More generally, this traditional perspective holds that international organizations and non-State actors only have an instrumental or merely accidental participation in custom-formation. In some variants of this perspective, the role of non-State actors in custom-formation is even denied. This dominant approach offers a convenient starting point for this discussion attempted in this volume. It simultaneously provides a sounding board for reflecting anew on the possible ways in which international organizations and non-State actors can be seen as contributing to the formation of customary law. This chapter also introduces the contributions in this volume and comments on the suggestions that the process of formation of customary international law be understood beyond the static, formal rule-making framework.