The FISA court represents a major constitutional crisis for our country, one which is going largely unnoticed by the public. By the EFF's account, the NSA's dragnet domestic surveillance can now be mined by the FBI to target U.S. citizens who are residing in the country, without a warrant, for any crime. And basically no one can appeal:
"[A] November 2015 ruling ... was unsealed this week. ... The ruling confirms that NSA's warrantless spying has been formally approved for use in general criminal investigations. The national security justification has been entirely blown.
That's because the secret court, over the objection of its hand-selected amicus, determined that once information is collected by the NSA for 'foreign intelligence' purposes under section 702 of the FISA Amendments Act, that information can be searched by the FBI for regular criminal investigations without any need for a warrant or prior court oversight.
... Section 702 is the law that the government uses to conduct two massive NSA programs: access to communications as they travel the Internet backbone (called Upstream) and access to communications stored with service providers like Google and Facebook (called Prism).
According to this ruling, communications like email and Facebook posts collected by the government under the broad authority of section 702 that the FBI has access to—including all 'raw' Prism data—can be mined for any 'evidence of a crime' and used against you, even if you're inside the United States.
... This FISC decision is flawed for all of these reasons. But we won't get a chance to present those flaws to the court of appeals, much less the US Supreme Court, because in cases before the secret surveillance court only the government, not the amicus (or those of us whose communications are swept up in these massive programs) is allowed to appeal."