MANHATTAN (CN) - The Department of Justice filed what seems to be its first legal defense of the National Security Agency's controversial data-collection practices since Edward Snowden leaked details of the secret operation.
"It is limited to telephony metadata, such as originating and terminating telephone numbers and the date, time and duration of each call," U.S. Attorney Preet Bharara said in a letter to filed in federal court in Manhattan.
The letter is the initial salvo from the government in its defense against a complaint filed by the American Civil Liberties Union last month.
The ACLU likened the NSA's "dragnet" collection of phone records for the secret surveillance program "to snatching every American's address book - with annotations detailing whom we spoke to, when we talked, for how long, and from where."
"It gives the government a comprehensive record of our associations and public movements, revealing a wealth of detail about our familial, political, professional, religious, and intimate associations," the complaint continues.
Such comprehensive access tramples on First Amendment guarantees of free association and Fourth Amendment protections against unreasonable search and seizure, the ACLU said.
Snowden brought the existence of the NSA program to light by sending the Guardian and the Washington Post a secret court order that forced Verizon to "turn over, every day, metadata about the calls made by each of its subscribers over the three-month period ending on July 19, 2013."
The ACLU said the government confirmed the authenticity of that order from the Foreign Intelligence Surveillance Court (FISC). Uncle Sam also allegedly indicated that the "order is part of a program that has been in place for seven years and that collects records of all telephone communications of every customer of a major phone company, including Verizon, AT&T, and Sprint."
Though the Patriot Act radically expanded surveillance powers of law enforcement agencies, the ACLU noted that the law still mandates a relevance showing for records targeted by an authorized investigation.
Echoing recent congressional testimony from the directors of the FBI and NSA, as well as public statements by President Barack Obama, the U.S. attorney told U.S. District Judge William Pauley that the government is not actually listening to or recording "just anyone's phone calls."
The secret court orders stipulated that the recorded information "cannot include cell-site location data or the names, addresses or identities of the parties to any communication," Bharara wrote Thursday.
When "specific facts" support "a reasonable, articulable suspicion" that a phone number in question is "associated with a specific foreign terrorist organization previously identified to and approved by the court," NSA analysts then query the database and provide "leads to the FBI or others in the Intelligence Community for counterterrorism purposes," according to the letter.
Bharara described the program as an "intelligence gap" that was "repeatedly reauthorized by multiple judges" as lawful, adding that the program is "highly sensitive and, in many respects, still classified."
The special court for foreign surveillance that approved the seizures of data was created as part of the Foreign Intelligence Surveillance Act, enacted 35 years ago after congressional investigation by committees chaired by Sen. Frank Church and Rep. Otis Pike.