An anonymous reader quotes a report from Bloomberg: Facebook in 2018 beat back federal prosecutors seeking to wiretap its encrypted Messenger app. Now the American Civil Liberties Union is seeking to find out how. The entire proceeding was confidential, with only the result leaking to the press. Lawyers for the ACLU and the Washington Post on Tuesday asked a San Francisco-based federal court of appeals to unseal the judge’s decision, arguing the public has a right to know how the law is being applied, particularly in the area of privacy. “It’s already publicly known that the Justice Department can’t wiretap Facebook’s messaging services,” Jennifer Granick, an attorney representing the ACLU, told the judges. “What isn’t known is the reason why.” The three judges didn’t tip their hand at the hearing conducted by video conference and said they would rule at a later date. “The Facebook case stems from a federal investigation of members of the violent MS-13 criminal gang. Prosecutors tried to hold Facebook in contempt after the company refused to help investigators wiretap its Messenger app, but the judge ruled against them,” adds Bloomberg. “If the decision is unsealed, other tech companies will likely try to use its reasoning to ward off similar government requests in the future.” Read more of this story at Slashdot.