It was organized on November 1, 1950, under authority provided in the McCarran Internal Security Act. The original 5 members of the panel were Seth W. Richardson of Washington, D.C., the Board's Chairman, along with Peter Campbell Brown of New York, Charles M. LaFollette of Indiana, David J. Coddaire of Massachusetts, and Dr. Kathryn McHale of Indiana. Mr. Brown later served as Chairman in 1952 and 1953.
The SACB was empowered to order the registration of organizations that it found to be "Communist fronts", "Communist action" groups or "Communist infiltrated" groups. In carrying out this mandate, the SACB was a leader in the U.S. government’s response to the Red Scare. The SACB’s proceedings were thorough and methodical. Hundreds of witnesses testified and were cross-examined by defense lawyers. The decisions and findings of the SACB were subject to judicial review.