3. Hierarchy of norms in international law

Abstract

This chapter examines the hierarchy of norms and sources in international law. Establishing a hierarchy of norms and sources allows for a community to elevate certain fundamental principles over ordinary norms, and to establish order and clarity in the relations between norms, authoritative institutions, and legal subjects. In the last half-century, a special class of general rules endowed with peremptory legal force has emerged. Known interchangeably as ‘peremptory norms’ or ‘norms of jus cogens’, these are regarded as possessing a higher status to ordinary rules of international law, and would prevail over the latter in cases of conflict. As such, whether an ordinary rule exists in treaty or customary law, or is a general principle, it is null and void if in conflict with a rule of jus cogens. The chapter also studies a related category known as rights, or, more commonly, obligations erga omnes (‘owed to all’).