A US federal appeals court in New York ruled today that the National Security Agency (NSA) programme systematically collecting US citizens' phone records is illegal.

Despite being authorised by two presidents, both Republican and Democrat, and being ruled legal by the legislative, judicial and executive branches of the US government, the NSA collection programme remains under fire.

The latest decision rules that the collection of metadata of phone calls to and from Americans is not authorised by Section 215 of the USA Patriot Act.

A panel of three federal judges said the USA Patriot Act, which had been used to justify the data collection program, cannot be legally interpreted to support the programme.

Unanimous decision

The case was brought to the courts by the American Civil Liberties Union (ACLU). A spokesperson for the ACLU says the ruling “should make clear, once and for all” that bulk collection of metadata is illegal.

Judge Gerard E. Lynch wrote on behalf of the unanimous decision “… we conclude that the district court erred in ruling that [Section 215 of the Patriot Act] authorises the telephone metadata collection program, and instead hold that the telephone metadata program exceeds the scope of what Congress has authorized and therefore violates [Section 215].”

Following the release of NSA documents by former technician Edward Snowden in 2013 revealing how and where the US security agency spies on the internet, the NSA has faced numerous attempts from US and foreign groups to limit its surveillance activity.

The Patriot Act, formulated under the Republican president George W Bush in response to the terror attacks of September 11, 2001, is due to expire in June this year. Congress has been debating over whether to extend the provision.

The US House of Representatives will vote on a bill next week that, if approved, could end the NSA metadata collection programme.

Two similar cases reviewing the programme are pending in separate appeals courts.

nsmith@nbr.co.nz