Foreign Intelligence Surveillance Act

The Foreign Intelligence Surveillance Act of 1978 is a United States federal law that established statutory procedures for authorizing electronic and physical surveillance of foreign powers and their agents, including within the United States, for foreign intelligence purposes. It was enacted following the Senate's Church Committee investigations of the mid-1970s, which had exposed years of warrantless domestic surveillance abuses by federal intelligence agencies, and it created the Foreign Intelligence Surveillance Court, a specialized federal court that reviews and approves surveillance applications largely in secret. The act has been amended repeatedly since its passage, most significantly by the USA PATRIOT Act after the September 11 attacks and by the FISA Amendments Act of 2008, which expanded the government's surveillance authority and added provisions addressing surveillance of communications involving Americans. It remains the primary statutory framework governing foreign intelligence surveillance in the United States.