The Department of Justice (DOJ) on Tuesday said it would appeal a ruling nullifying the federal mandate for masks on planes and other public transit if the Centers for Disease Control and Prevention (CDC) determines that a “mandatory order remains necessary for the public’s health.” “The Department continues to believe that the order requiring masking in the transportation corridor is a valid exercise of the authority Congress has given CDC to protect the public health,” DOJ spokesman Anthony Coley said in a statement Tuesday evening. “That is an important authority the Department will continue to work to preserve.”