The Supreme Court was asked in a petition to force the government to disclose the US clandestine plan to disable cell service during emergencies.

The case concerns Standard Operating Procedure 303. A federal appeals court in May said the government did not have to release its full contents because the Freedom of Information Act (FOIA) allows the authorities to withhold records if they would "endanger" public safety.

The Electronic Privacy Information Center told the high court's justices Tuesday that the US Court of Appeals for the District of Columbia Circuit's decision created a new "catchall provision that can be used in any case involving records related to domestic and national security programs." (PDF)

The privacy group had demanded the documents from the Department of Homeland Security in 2011 following the shuttering of cell service in the San Francisco Bay Area subway system to quell a protest. The Department of Homeland Security refused to divulge the documents associated with SOP 303, which the appeals court described as a "unified voluntary process for the orderly shut-down and restoration of wireless services during critical emergencies such as the threat of radio-activated improvised explosive devices."

Under the direction of the so-called National Security Telecommunications Advisory Committee, SOP 303 allows for the shuttering of wireless networks "within a localized area, such as a tunnel or bridge, and within an entire metropolitan area."

The telecoms have agreed to shutter service when SOP 303 is invoked, but there are no publicly disclosed instances of the measure ever being invoked.