The Function of Jus Cogens in the Field of Unilateral Acts of States

The concept of jus cogens entered into international law through the law of treaties and today has become one of the most important and effective rules of international law. The principal and recognized function of the jus cogens is to invalidate any treaty which is in conflict with it. Some States resort to unilateral acts to achieve their goals and to avoid the limitations imposed by the  jus cogens, because given the lacuna in international law, they consider those acts to be outside the influence of the jus cogens. In recent years, we have seen the functional development of the jus cogens in areas other than the law of treaties. This article, examines the function of jus cogens in the field of unilateral acts of States, to determine if unilateral acts of States, where they conflict with a peremptory norm, produce any legal consequences, and if the jus cogens has any impact on such acts, is its function in the field of unilateral acts similar to that of the law of treaties or does it has a different function.