The relationship between peremptory norms of general international law (jus cogens) and obligations erga omnes

Abstract

No clear test for the identification and determination of obligations erga omnes exists, such obligations are normally defined by reference to the notion of jus cogens norms. It is mostly agreed that jus cogens norms give rise to obligations erga omnes, however, not all obligations erga omnes flow from jus cogens norms. Thus pragmatically, although the use of jus cogens to identify, determine and assess obligations erga omnes might be fruitful, it is not always conclusive. This study accepts that the relationship between these two notions is a matter of considerable complexity as both of these concepts pose great difficulties and eschew an easy classification.

In light of this, the study seeks to identify the legal framework governing the identification of obligations erga omnes, particularly for norms that have not reached the status of jus cogens, or at the very least, determine erga omnes without placing reliance on whether the obligation in question arises from a norm with jus cogens status. The study is undertaken to provide some conceptual clarity as regards the relationship between jus cogens norms and obligations erga omnes, as well as to confirm or otherwise disprove the allegation that the two concepts must be conflated.