Judge La Buy (P) asked the parties to an antitrust action to have a master hear the cases. P reasoned he did not have the time to hear a six-week case and wanted to refer it to a master under Rule 53(b). The parties did not respond. P entered an interlocutory order, sua sponte, and referred the cases to a master. Howes Leather Co. (D) filed for a writ of mandamus, asking the court of appeals to compel P to vacate the reference to the master. The court of appeals issued a writ of mandamus under the All Writs Act (28 U.S.C. §1651[a]). P sought certiorari to the U.S. Supreme Court, attacking the writ.