The Maine Public Utilities Commission plan to file a formal response Wednesday in advance of a court hearing Thursday in U.S. District Court in Bangor.
The justice department has asked a federal judge to bar the P.U.C. from moving forward with a contempt hearing scheduled for Friday.
It all began with a customer complaint that would force the phone company to say whether it provided call records to the government without a warrant.
The justice department says the questions involve national security and cannot be disclosed for fear of revealing classified intelligence activities.