The Obligation to Cooperate to Protect Against Serious Breaches of the European and American Conventions on Human Rights

This paper discusses the obligation of States to co-operate as a duty that stems from two different areas of international law. First, States are obliged to co-operate under the law of State responsibility, the aim of co-operation within this framework being to bring to an end serious breaches of peremptory norms. The second area is interna-tional human rights law and, in particular, the European (ECHR) and the American Conventions on Human Rights (ACHR), as these instruments have been interpreted by the respective regional human rights courts to encompass a procedural obligation for States to co-operate with a view to protect human rights. The paper asks whether the obligation to cooperate, as constructed by the two regional human rights courts, has any overlap with the obligation to cooperate under the law of State responsibility, and,if yes, whether it can and does cross-fertilise the interpretation of the latter. The analy-sis of the relevant case law provides two affirmative answers. First, there is common space between the obligations to cooperate under the law of State responsibility, the ECHR, and the ACHR. Second, analysis also identifies certain features in the relevant human rights case law that enrich the obligation to co-operate under the law of State responsibility. These features are the effectiveness in the protection of the most fundamental norms and interpretation of the duty to cooperate through systemic integration. Systemic integration is necessary to concretise the conduct States are expected to develop as the obligation to cooperate refers to a rather open list of relevant rules of international law applicable to that State.