Customary International LawSymposium

Why customary international law matters in protecting human rights

Does customary international law really matter in protecting human rights, and if so how? This was the theme of a panel at International Law Weekend in New York on October 20, 2018. International Law Weekend is an annual conference organized by the American Branch of the International Law Association. The panel was sponsored by the American Branch’s Committee on the Formation of Customary International Law, of which I serve as chair. …



Customary international law identification as constrained law-making

A response to David Koppe There has been a resurgence of interest in recent years in how customary international law is identified, and this interest will likely intensify as a result of the International Law Commission’s current work on the subject. Somewhat ironically, this resurgence of interest comes at a time when there are increasing doubts about the continued usefulness of customary international law in addressing the world’s problems, and …



Ascertaining Customary International Law – a relatively straightforward matter?

This blog post refers to the recent findings of the International Law Commission’s (ILC) topic now entitled “Identification of Customary International Law” and addresses some issues, which still remain unsettled even in its current third report (A/CN.4/682) and which call for further considerations. Irrespective of the dispute about the proper theory of customary international law a settled methodology for ascertaining the existence of a rule of customary international law is …