EFF: 702 Spying: Backdoor Search:
The Fourth Amendment prohibits unreasonable searches, which typically means that the government has to get a warrant if it wants to search your home or read your emails. But under Section 702, there’s a glaring loophole.
Section 702 is the surveillance authority enacted as part of the FISA Amendments Act in 2008 and set to expire at the end of this year.
In theory, this provision of the Foreign Intelligence Surveillance (FISA) Act is just that: aimed at collecting foreign intelligence, possessed by foreigners who the Supreme Court has said are outside the scope of the Fourth Amendment’s protections.
But in reality, Section 702 sweeps in millions of Americans’ communications, including through “downstream” surveillance, or the intelligence agencies’ collection of communications directly from the companies that Internet users rely on to communicate, including Google, Facebook, and Yahoo.