[Latin: coercive law]
A rule or principle in international law that is so fundamental that it binds all states and does not allow any exceptions. Such rules (sometimes called peremptory norms) will only amount to jus cogens rules if they are recognized as such by the international community as a whole. A treaty that conflicts with an existing jus cogens rule is void, and if a new jus cogens rule emerges, any existing treaty that conflicts with it automatically becomes void. States cannot create regional customary international law that contradicts jus cogens rules. Most authorities agree that the laws prohibiting slavery, genocide, piracy, and acts of aggression or illegal use of force are jus cogens laws. Some suggest that certain human rights provisions (e.g. those prohibiting racial discrimination) also come under the category of jus cogens.