Sovereignty can generally be defined as supreme authority. Sovereignty entails hierarchy within the state, as well as external autonomy for states. In any state, sovereignty is assigned to the person, body or institution that has the ultimate authority over other people in order to establish a law or change existing laws. In political theory, sovereignty is a substantive term designating supreme legitimate authority over some polity. In international law, sovereignty is the exercise of power by a state. De jure sovereignty refers to the legal right to do so; de facto sovereignty refers to the factual ability to do so. This can become an issue of special concern upon the failure of the usual expectation that de jure and de facto sovereignty exist at the place and time of concern, and reside within the same organization.