Peremptory norm

A peremptory norm (also called jus cogens)^[1] is a fundamental principle of international law that is accepted by the international community of states as a norm from which no derogation is permitted.

There is no universal agreement regarding precisely which norms are jus cogens nor how a norm reaches that status, but it is generally accepted that jus cogens bans genocide, maritime piracy, enslaving in general (i.e. slavery as well as slave trade), wars of aggression and territorial aggrandizement, and generally as well torture, and refoulement.^[2]