"grandfather clause"

Definition: In 1870, after African Americans were given the right to vote through the 15th Amendment, some Southern states added grandfather clauses to their state Constitutions to counter this new right. Typical clauses stated that the right to vote extended only to citizens or their descendants who had the right to vote prior to 1866 or 1867. The U.S. Supreme Court declared grandfather clauses unconstitutional in 1915 and in 1939.