A federal appeals court won't force the US to disclose its clandestine plan to disable cell service during emergencies.

That was the decision from the US Court of Appeals for the District of Columbia Circuit concerning Standard Operating Procedure 303. The court had taken the same position in February and agreed with the government's contention that the Freedom of Information Act (FOIA) allows the Department of Homeland Security to withhold documents if their exposure could "endanger" public safety.

After the decision, the Electronic Privacy Information Center (EPIC), which brought the FOIA suit, had asked the court to revisit the issue in what is known as an en banc review. The appeals court declined (PDF) in a one-sentence order Wednesday.

The privacy group had demanded the document way back in 2011 following the shuttering of cell service in the San Francisco Bay Area subway system to quell a protest. The DHS 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."

EPIC sued and won the case in the lower courts. The DHS appealed.

In its petition for a rehearing, EPIC argued that the appellate court's decision "created a catch-all provision that would allow federal agencies to routinely withhold records subject to disclosure where the agency merely asserts a speculative security risk."

SOP 303 allows for the shutting down of wireless networks "within a localized area, such as a tunnel or bridge, and within an entire metropolitan area."