[JURIST] The Foreign Intelligence Surveillance Court (FISC) [official website] released a previously classified opinion [text, PDF] on Tuesday explaining why a National Security Agency (NSA) [official website] program to keep records of Americans’ phone calls is constitutional. The opinion, written by US district court judge Claire Eagan [official profile], said that security leaks regarding the NSA surveillance programs [JURIST backgrounder] have jeopardized national security [NYT report]. Eagan also emphasized that the political branches of government, rather than the courts, should make decisions about whether to keep or discontinue the surveillance programs:

This court is mindful that this matter comes before it at a time when unprecedented disclosures have been made about this and other highly sensitive programs designed to obtain foreign intelligence information and carry out counterterrorism investigations. In the wake of these disclosures, whether and to what extent the government seeks to continue the program discussed in this memorandum opinion is a matter for the political branches to decide.

Eagan’s decision was the first written court opinion to be released since the program came to light earlier this year.

The revelations surrounding NSA surveillance programs have sparked worldwide debate and controversy. Earlier this week the American Civil Liberties Union (ACLU) [advocacy website] urged the Obama administration [JURIST report] to curb the FBI’s surveillance powers. Last month the Council of Europe [official website] expressed concern [JURIST report] over the UK reaction to the exposure of the US surveillance program. In June the ACLU in conjunction with the New York Civil Liberties Union [advocacy website] filed suit [JURIST report] against the NSA challenging its recently revealed phone data collection. Although the president and top officials have defended the surveillance as a lawful counterterrorism measure, several US lawmakers have called for a review [JURIST report] of the government’s surveillance activity in light of recent reports revealing phone and Internet monitoring. Lawmakers have also called for a criminal investigation into the activities of Edward Snowden, who came forward in early June as the whistleblower in the NSA surveillance scandal [JURIST podcast]. JURIST Guest Columnist Christina Wells argues that the broad provisions of the Espionage Act [text], under which Snowden is charged, raise significant First Amendment concerns [JURIST op-ed].