Common Article 1 of the Geneva Conventions and the Method of Treaty Interpretation

Abstract In its updated Commentaries on the 1949 Geneva Conventions, the International Committee of the Red Cross (ICRC) embraces the ‘external’ interpretation of Article 1 common to the four Geneva Conventions, according to which States have certain negative (complicity-type) and positive (prevention/response) obligations to ‘ensure respect’ for the Conventions by other actors. This interpretation has been gaining support since the 1960s, though the ICRC's new Commentaries have served as a catalyst for some States recently to express contrary views. This article focuses on two major methodological shortcomings in the existing literature, offering a much firmer foundation for the external obligation under common Article 1. First, it demonstrates the overwhelming support in subsequent practice for external obligations. Previous studies have failed to explain the method by which this practice is taken into account, given the existence of some inconsistent practice. This article addresses this general question of treaty interpretation, critiquing the approach of the International Law Commission that relegates majority practice to supplementary means of interpretation and proposing instead a principled approach that better fits and justifies the judicial practice here. Secondly, the article challenges two common assumptions about the travaux : first, that an original, restrictive meaning was intended, and secondly that the travaux of Additional Protocol I offer no support for external obligations. Given the ubiquity of military assistance and partnering, these findings have far-reaching consequences for the liability of States.