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.
The frontispiece of Thomas Hobbes' Leviathan, depicting the Sovereign as a massive body wielding a sword and crosier and composed of many individual people
Authority is commonly understood as the legitimate power of a person or group over other people. In a civil state, authority is practiced by the legislative, executive, and judicial branches of government. The term authority has many nuances and distinctions within various academic fields ranging from sociology to political science.
The Supreme Court of the United States is the highest judicial authority in the United States of America.