The Responsibility Not to Veto Revisited under the Theory of ‘Consequential Jus Cogens’

In this article, I argue that contemporary international law imposes an obligation upon the UN Security Council permanent members to refrain from using their veto repeatedly in ways that impede the Council from acting against violations of peremptory norms. This obligation not to veto emanates from the duty to cooperate to end violations of peremptory norms as enshrined in Article 41(1) of the International Law Commission Articles on State Responsibility. For this purpose, I demonstrate that the duty to cooperate itself possesses a peremptory character under the theory of ‘consequential jus cogens’, whereby effects of jus cogens norms are themselves peremptory. In doing so, this article contributes to the ongoing debates concerning the legal nature of the effects of jus cogens norms by showing that the theory of ‘consequential jus cogens’ is an application of the generally accepted maxim accessorium sequitur principale and thus forms part of positive international law.