Sources and the enforcement of international law: What norms do international law-enforcement bodies actually invoke?

This chapter analyses the sources of law used by international law-enforcing bodies. It discusses the practice of international and domestic bodies and juxtaposes the sources of international law norms on which such bodies rely with the list of international law sources found in Article 38 (1) of ICJ Statute. The chapter offers in this connection two interrelated surveys: a categorization of the main bodies that engage in international law enforcement, and an overview of the process of law enforcement pertaining to two particular sets of norms. These surveys underlie the contention that Article 38 does not necessarily predict well which international law norms are likely to be invoked in practice by law-enforcement bodies. The chapter concludes with a discussion of some of the explanations for the differences between the general list of sources of international law and the sources relied upon by international law-enforcement bodies.