In January 1975, in the wake of the Watergate scandal, the Senate set up an 11-member Select Committee to Study Governmental Operations with Respect to Intelligence Activities. It was chaired by Senator Frank Church (D-Idaho).

The Church Committee proved more robust and far-ranging in its investigations than the Rockefeller Commission, and issued 14 reports in 1975 and 1976 on the NSA, CIA, FBI and IRS.  More than 50,000 pages have been declassified, and many can be read online.