Jus cogens

A type of custom that cannot be avoided.



Vienna Convention (VCLT) is an important document that references jus cogens norms. They have also been supported and referenced in ICJ decisions. They are regarded to obligations erga omens i.e. owed to all. There is some controversy as to which rules of customary law are jus cogens norms. There is a short list of generally accepted jus cogens norms: you cant invade another state unless you have security council approval or are acting in self defence (prohibition on use of force); the international crimes under IL such as slavery, piracy, apartheid, torture.