Complex sentence: The Non-Detention Act of 1971 was passed to repeal portions of McCarran Internal Security Act of 1950, specifically Title II, the "Emergency Detention Act" PBS documentary "Trumbo", which allowed for detention of suspected subversives without the normal Constitutional checks required for imprisonment.
Split into simpler sentences: The Non-Detention Act of 1971 was passed to repeal portions of McCarran Internal Security Act of 1950, PBS documentary "Trumbo", specifically Title II, the "Emergency Detention Act". It allowed for detention of suspected subversives without the normal Constitutional checks required for imprisonment.