The NSA's mass phone-call data-gathering programme provided only negligible effects to fight terrorism and should end, the US Privacy and Civil Liberties Oversight Board has concluded.
In a report released on Thursday, the board – a US federal privacy watchdog – claimed the eavesdropping programme was illegal and recommended all data collected be discarded.
The report comes as US President Barack Obama and the Congress are working to reform the NSA’s infamous surveillance programme that has been facing international backlash since revelations made by former NSA contractor Edward Snowden.
The Privacy and Civil Liberties Oversight Board, formed at the recommendation of the 9/11 Commission in 2004 to ensure counterterrorism measures are not breaching privacy of Americans, has reviewed public and classified documents. It found no terrorist attacks have been thwarted or previously unknown terrorist plots discovered through the programme in the previous seven years.
"The Section 215 bulk telephone records programme lacks a viable legal foundation under Section 215, implicates constitutional concerns under the First and Fourth Amendments, raises serious threats to privacy and civil liberties as a policy matter, and has shown only limited value," the report said.
The board's majority argued that the NSA improperly relies on a statute meant to give the FBI access to phone records. It also questioned the relevance of collecting metadata – records of US phone calls, their length and time – in bulk and its routine reauthorisation by a secretive surveillance court.
The board said other existing laws could be used to access phone records if needed.
"It's time to push the reset button" on the programme, said board member James Dempsey, public policy vice president at privacy advocacy group Center for Democracy and Technology.
Two of the board's Republican members – Rachel Brand, former lawyer at the US Chamber of Commerce and the Justice Department, and Elisebeth Collins Cook, former assistant attorney general at the Justice Department – voted against the recommendation to end the NSA's bulk record collection.
"I'm concerned the report gives insufficient weight to the need for a proactive approach to combating terrorism," said Brand during the public presentation of the board's report.
Congress is already sharply divided over what to do with the telephone metadata collection programme, which collects data on millions of phone calls made in the United States but not the content of the calls.
Intelligence committees in both Houses recommend that current collection and storage arrangements be maintained, while Judiciary committees have recommended that such collection be outlawed.
Obama, in his own speech on NSA reforms on Friday, did not call for an outright halt to the collection of phone metadata by the NSA, although agreed that the storage of telephone metadata should be moved out of government and should not be searched without judicial approval.