The Church Committee was created on January 27, 1975, after New York Times reporter Seymour Hersh revealed the CIA's illegal domestic surveillance activities. The committee, formally called the U.S. Senate Select Committee to Study Governmental Operations with Respect to Intelligence Activities, was chaired by Sen. Frank Church (D-ID) and approved by an 82-to-4 vote.
The committee interviewed 800 witnesses, reviewed 110,000 classified documents, and published its final report with 96 recommendations in April 1976. Investigations uncovered CIA assassination plots against foreign leaders, the 1953 Iran coup, illegal mail-opening of 215,000 pieces of mail, and NSA surveillance of American citizens.
The committee's work led to the creation of the Senate Select Committee on Intelligence (1976), the House Permanent Select Committee on Intelligence (1977), and the Foreign Intelligence Surveillance Act (FISA) of 1978. These form the oversight system that governs CIA operations today.