Lawmakers on Wednesday blasted United States intelligence agencies for trampling on privacy rights and vowed to impose limits on the government's authority to scoop up Americans' phone records.
At a House Judiciary Committee hearing, members from both parties berated senior officials over the collection of bulk phone data as beyond the limits of the US Constitution as well as legislation adopted by Congress.
"I think that very clearly, this programme has gone off the tracks legally," said representative Zoe Lofgren of California.
The hearing focused on the government's far-reaching surveillance activities that have come under intense scrutiny after leaks from a former intelligence contractor, Edward Snowden, who revealed that the National Security Agency (NSA) was collecting phone "meta-data" and trawling through internet traffic to look for terror suspects.
But senior justice and intelligence officials insisted the data mining of phone records was reviewed by a secret court, in line with laws adopted by Congress and only conducted to track down Al-Qaeda-linked militants.
"With these programmes and other intelligence activities, we are constantly seeking to achieve the right balance between the protection of national security and the protection of privacy and civil liberties," deputy attorney general James Cole told the committee.
Lawmakers, however, said Congress had amended the post-9/11 Patriot Act to ensure phone or other business records would only be collected on a narrow basis, when government agencies had a specific suspect or threat in mind.
"We amended the Patriot Act to avoid this very same problem," said John Conyers, the senior-ranking Democrat on the committee, who called the data collection a "serious violation" of the law. "This is unsustainable, it's outrageous and must be stopped immediately," Conyers said.
Venting frustration with the Obama administration's stance, Republican James Sensenbrenner warned the authority for gathering phone data - known as Section 215 of the Patriot Act would not be renewed unless the government changed its approach.
"You have to change how you operate Section 215, otherwise you're not going have it anymore," he said.
Administration officials told the committee that the phone data allowed spy agencies and the Federal Bureau of Investigation to track down an associate of Najibullah Zazi, who admitted to plotting to bomb the New York City subway.
The officials also said the government was conducting only a relatively small number of searches through the phone data, despite the large volume of telephone records collected, and that it was barred from looking for any information on crimes unrelated to terror threats.
The NSA carried out searches of phone records in 2012 using fewer than 300 "unique identifiers," said NSA deputy director John Inglis. "Only 22 people at the NSA are allowed to approve the selectors (information) that are used to launch a search in this database," he said.
But privacy advocates were taken aback by other comments by Inglis that suggested the government looks at a far larger universe of data than previously stated, saying that analysts examine information "two or three hops" - two or three steps removed — from a terror suspect.
Most of the judiciary committee members dismissed the explanations offered by administration officials, saying the court that reviews the spying operations operated under a veil of secrecy.
The Foreign Intelligence Surveillance Act court was set up in the 1970s after a Senate enquiry exposed scandals and abuses by the spy agencies, including snooping on anti-war activists and other dissidents.
The FISA court has the power to grant warrants when the government requests permission to carry out surveillance of terrorist suspects or "agents of foreign powers".
But the proceedings and decisions are all kept secret, and lawmakers said on Wednesday the government had to lift the lid on the FISA court's work to ensure public confidence in the surveillance programs.
Conyers said releasing the court's rulings would allow lawmakers to hold public debates on the data collection policies, which was nearly impossible now due to the secrecy surrounding the programs.
Over more than 30 years, the FISA court has only rejected 11 of 34,000 requests from the intelligence agencies.
Some lawmakers have proposed restructuring the court, making it more transparent and possibly adding a privacy advocate to force the government to argue its case in an adversarial setting, similar to regular courts.