Last February, a sharply divided Supreme Court threw out an attempt by U.S. citizens to challenge the expansion of the surveillance law used to monitor conversations of foreign spies and terrorist suspects.

In a 5-4 vote, the court ruled that a group of American lawyers, journalists and organizations could not sue to challenge the 2008 expansion of the law because they could not prove that the government would monitor their conversations along with those of potential foreign terrorist and intelligence targets.