NSA warrantless surveillance (2001–2007)

NSA warrantless surveillance — also commonly referred to as "warrantless-wiretapping" or "-wiretaps" — was the surveillance of persons within the United States, including U.S. citizens, during the collection of notionally foreign intelligence by the National Security Agency (NSA) as part of the Terrorist Surveillance Program. In late 2001, the NSA was authorized to monitor, without obtaining a FISA warrant, phone calls, Internet activities, text messages and other forms of communication involving any party believed by the NSA to be outside the U.S., even if the other end of the communication lay within the U.S. Critics claimed that the program was an effort to silence critics of the Bush administration and its handling of several controversial issues.

Source: Wikipedia — NSA warrantless surveillance (2001–2007) (CC BY-SA 4.0)