The Guardian also reported that no court orders were needed, and that the agency could dip into the servers of Google and others both to monitor real-time communication as well as to pull out archived data.
"The presentation claims PRISM was introduced to overcome what the NSA regarded as shortcomings of FISA warrants in tracking suspected foreign terrorists," the report said.
The surveillance activities used in the PRISM program may be based on provisions in the FISA Amendments Act of 2008, which authorizes the government to monitor electronic communications if one of the communicating parties is believed to be outside the U.S. Critics say the law allows for the warrantless surveillance of electronic communications such as email and phone calls, of not only foreigners but U.S. citizens. An ACLU lawsuit challenging the law's constitutionality was dismissed 5-4 by the Supreme Court last February.
"If the Washington Post story checks out, what they [the NSA and FBI] did is illegal, EFF's Cardozo says. "The FISA Amendments Act was not meant to authorize anything of this scope."
The Guardian's report also noted that the U.S. has a "home-field advantage" due to housing much of the internet's architecture. But the presentation claimed that "FISA constraints restricted our home-field advantage" because the law required individual warrants and confirmations that both the sender and receiver of a communication were outside the U.S."
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