Internal Security Act of 1950

The Internal Security Act of 1950, also referred to as the McCarran Internal Security Act of 1950 and the Subversive Activities Control Act of 1950, became law on September 22, 1950, by congressional resolution. The act required that all communist and related political organizations be registered with the U.S. attorney general. Because of the constitutional questions with requirements of the act, President Harry S. Truman vetoed the law and sent it back to Congress. The law went into effect after both houses voted to override the veto.

In the early 1950s, ...