(Internal Security Act) a law adopted by the Congress of the USA on Sept. 23, 1950, and sponsored by Senator McCarran and Representative Wood.
Along with the Smith Act of 1940 and the Brownell-Butler Act of 1954, the McCarran-Wood Act provided a legal basis for persecuting the Communist Party and left-wing radical and democratic organizations. Initially the McCarran-Wood Act provided for the compulsory registration at the Department of Justice of all organizations of the Communist Party and so-called Communist front groups as “subversive” elements or “agents of a foreign state”; it also called on these organizations to submit information on all persons holding office and figures on membership and financial activity.
After many years of struggle, the Communist Party of the USA succeeded in establishing the unconstitutionality of the McCarran-Wood Act with regard to registration (the decision of the US Supreme Court was rendered in November 1965). The persecution of the Communist Party in the courts was halted in 1967. Subsequently, the US Supreme Court declared unconstitutional other anti-Communist sections of the McCarran-Wood Act, including the prohibition against members of the Communist Party working in defense industries (December 1967).