Congress to begin review of FISA surveillance powers that expire in 2017
Will Congress rein in the NSA's ability to spy on Americans?
Lawmakers want to know how often U.S. spies incidentally collect Americans' data
'We are not the first to ask you for this basic information.'
Civil-liberties groups ask the government to detail surveillance statistics
More than two dozen groups want answers.
NSA's Internet spying program totally legal, Obama review board finds
The Privacy and Civil Liberties Oversight Board found "no trace" of illegal activity.