The Foreign Intelligence Surveillance Act of 1978 (FISA) was enacted on October 25, 1978 and is codified at 50 U.S.C. ch. 36.
The Act has been amended several times, most notably by the Foreign Intelligence Surveillance Act of 1978 Amendments Act of 2008 (FISA Amendments Act of 2008) on July 10, 2008.
See J. Douglas Wilson & David Kris' National Security Investigations and Prosecutions § 4:2, History and Scope for a summary and detailed information about the Act's other amendments. Also see Kris' "How the FISA Court Really Works" post on Lawfare (9/2/18) for more information about the FISA Court.
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