San Francisco: A secret court overseeing US government domestic surveillance activities has sided with Yahoo and ordered the Obama administration to declassify and publish a 2008 court decision justifying Prism, the data collection program revealed last month by former security contractor Edward Snowden.

Judge Reggie Walton of the Foreign Intelligence Surveillance Court issued Monday's ruling. The government is expected to decide by August 26 which parts of the ruling may be published, according to a separate court filing by the Justice Department.

The US Foreign Intelligence Surveillance Court, which reviews government requests to spy on individuals, ruled information should be made public about a 2008 case that ordered Yahoo Inc. to turn over customer data. Credit:AP

Controversial US data collection activities are overseen by the Foreign Intelligence Surveillance Court and its appeals body, the Foreign Intelligence Surveillance Court of Review. Both have been shrouded in secrecy since their creation more than three decades ago.

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