Jus Cogens : An exception to State Immunity ?

In accordance with the hierarchy of norms in International Law, Jus Cogens are peremptory norms which trump any other norms. They are norms from which no derogation is allowed. However, a problem arises when Jus Cogens is faced with State Immunity, a custom of International Law which protects states from prosecution by foreign states. Indeed, this becomes an issue when a state violates a peremptory norm which it is not allowed to do but because of State Immunity, no foreign state can hold that state accountable for this violation because it enjoys immunity against jurisdiction by foreign states. Since no derogation is allowed from Jus Cogens, the logical solution should be that the jurisdictional immunity of States be waived when they violate Jus Cogens norms. Thus, making Jus Cogens an exception to the immunity of States. This thesis aims at seeing if in practice, Jus Cogens is accepted or not as an exception to State Immunity by scholars, judges and states in general.