Rights or powers retained by the regional governments of a federal union under the provisions of a federal constitution.
In the U.S., Switzerland, and Australia, the powers of the regional governments are those that remain after the powers of the central government have been enumerated in the constitution. The powers of both the state or regional and national levels of government are defined clearly by specific provisions of the constitutions of Canada and Germany. The concept of states' rights is closely related to that of the 18th-century European concept of state rights, which was invoked to legitimate the powers vested in sovereign national governments. In the U.S. before the mid-19th century, some Southern states claimed the right to annul an act of the federal government within their boundaries (see nullification ), as well as the right to secede from the Union. The constitutional question was resolved against the South by the North's victory in the American Civil War . In the civil rights era, states' rights were invoked by opponents of federal efforts to enforce racial integration in public schools. The federal government can influence state policy even in areas that are constitutionally the purview of the states (e.g., education, local road construction) through withholding funds from states that fail to comply with its wishes. In the late 20th century the term came to be applied more broadly to a variety of efforts aimed at reducing the powers of national governments.