Statute also known as the Internal Security Act that aimed at stopping communist subversion in the United States.
The McCarran Act, sponsored by Senator Patrick A. McCarran of Nevada, attacked the alleged communist threat. It created a Subversive Activities Control Board that could, with approval of the U.S. attorney general, order an organization that it found to be communist to register with the Justice Department and submit information concerning its membership, activities, and finances. Furthermore, the act prohibited known communists from being employed by the federal government, denied them the right to use U.S. passports, and made it a felony for anyone to attempt to establish a totalitarian dictatorship in the United States. Another provision arranged for emergency arrest and detention of any person likely to commit espionage or sabotage.
President Harry S Truman immediately vetoed the act on the grounds that it violated the Bill of Rights, but his veto was overridden by an 89 percent majority vote. McCarran’s newly formed Senate Internal Security Subcommittee worked closely with the Federal Bureau of Investigation and conducted hearings for the next twenty-seven years in an attempt to enforce the act. In Communist Party v. Subversive Activities Control Board
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