The Notion of Institutional Practice in United Nations Law

This paper aims to define the notion of institutional practice and it examines the extent to which United Nations organs and Member States can rely on and are limited by it. It describes all the normative theories involved, and proposes a simplified and comprehensive framework. The core argument is that institutional practice is less relevant than it seems in the first instance and, generally, it cannot do much by itself. It requires a further element to produce normative effects, whether in the form of Member States’ practice or other means of interpretation of the constitutive instrument. After a brief introduction, the second section focuses on what constitutes institutional practice, distinguishing between the problem of the acts that constitute practice and how they are attributed to the organisation. Section iii discusses its employment by the International Law Commission, which distinguishes ‘subsequent’ institutional practice as a means of interpretation of the constitutive instrument, ‘general’ institutional practice as an element of customary law, and ‘established’ institutional practice as a rule of the organisation. Finally, Section iv provides a general overview of the normative relevance of institutional practice. The Conclusion summarizes these main findings.