FISA, Section 702, Section 215, and FISC
FISA orders issue from the FISC on probable cause that the target is a foreign power or agent, not probable cause of a crime, when foreign intelligence is a significant purpose. Section 702 authorizes PRISM and Upstream collection targeting non-U.S. persons abroad. Section 215 bulk collection ended; the provision expired in 2020.
Foreign Intelligence Surveillance Act (FISA) orders issue from the Foreign Intelligence Surveillance Court (FISC) on probable cause that the target is a foreign power or an agent of a foreign power (not probable cause of a crime), when foreign intelligence is a significant purpose. The USA FREEDOM Act added an amicus curiae of privacy and civil-liberties experts. FISA targets generally are not notified, but transparency has increased over time, and FISA orders now outnumber traditional law-enforcement wiretaps.
Section 215 drew attention after Snowden disclosed an NSA database of domestic call detail records; the USA FREEDOM Act ended its bulk collection and the provision expired in 2020.
Section 702 (from the 2008 FISA Amendments Act) authorizes collecting communications of targeted persons the government reasonably believes are non-U.S. citizens located outside the United States for foreign intelligence purposes, including full content. The FISC annually approves certifications and targeting criteria. Its two programs are PRISM and Upstream: PRISM sends judicially approved directives to U.S.-based providers for specific selectors; Upstream filters communications passing through U.S. internet infrastructure for a tasked selector.
An ordinary law-enforcement order rests on probable cause of a crime. A FISA order rests on probable cause that the target is a foreign power or agent - a different standard - and is issued by the secret FISC.