In 1954, Abner Green, executive secretary of the American Committee for the Protection of Foreign Born (ACPFB), was sentenced by a New York State grand jury to serve six months in a federal prison.

His crime? Green refused to turn over financial records, including lists of contributors to both the ACPFB, an immigrant rights organization serving foreign-born people around the country, and the Civil Rights Congress (CRC), an advocacy group for racial justice where he served on the board of directors. The grand jury also imposed an extra six-month sentence on Green because he declined to turn over records for the ACFPB’s bail fund.

The investigation of the ACPFB was facilitated by the Internal Security Act of 1950. Part of the anti-communist mobilization known as McCarthyism, the bill created a Subversive Activities Control Board, the organization that initially subpoenaed the organizational records from Green. Organizations like the ACPFB were investigated by the board and, if confirmed to be “Communist fronts,” organizations that weren’t officially Communist but were backed by the party, had to register with the federal government, limiting their political activities. Additionally, the law made it a felony to support what it described as “totalitarian dictatorship” and authorized the president to arrest and detain those suspected of espionage or subversion.