https://portside.org/2017-12-18/secret-court

'The 11-member Foreign Intelligence Surveillance Court, known as the FISA court, was once mostly focused on approving case-by-case wiretapping orders. But since major changes in legislation and greater judicial oversight of intelligence operations were instituted six years ago, it has quietly become almost a parallel Supreme Court, serving as the ultimate arbiter on surveillance issues and delivering opinions that will most likely shape intelligence practices for years to come, the officials said.'