United States v. Mueller was a United States Supreme Court case that addressed the issue of whether a federal court had the authority to issue a writ of habeas corpus to a prisoner held in state custody. The case involved a prisoner, Mueller, who was convicted of a crime in the state of Wisconsin and sentenced to a term of imprisonment. Mueller then filed a petition for a writ of habeas corpus in the United States Circuit Court for the Eastern District of Wisconsin, seeking to be released from his state custody. The Circuit Court granted the writ, and the United States appealed the decision to the Supreme Court. The Supreme Court held that the Circuit Court did not have the authority to issue the writ of habeas corpus. The Court reasoned that the writ of habeas corpus is a remedy that is available only to federal prisoners, and that the Circuit Court did not have the authority to issue the writ to a prisoner held in state custody. The Court further held that the writ of habeas corpus is a remedy that is available only to federal prisoners, and that the Circuit Court did not have the authority to issue the writ to a prisoner held in state custody. In conclusion, the Supreme Court held that the Circuit Court did not have the authority to issue the writ of habeas corpus to a prisoner held in state custody. The Court reasoned that the writ of habeas corpus is a remedy that is available only to federal prisoners, and that the Circuit Court did not have the authority to issue the writ to a prisoner held in state custody.

In United States v. Mueller, the Supreme Court was asked to decide whether a federal court had jurisdiction over an action brought by the United States against a defendant who was alleged to have committed fraud in connection with his duties as postmaster of a small town in Wisconsin. The majority opinion held that because Congress had not specifically granted such jurisdiction, it did not exist and therefore the case should be dismissed. Justice Field dissented from this decision, arguing that under Article III of the Constitution, which grants Congress authority “to make all laws necessary and proper for carrying into execution” its powers enumerated therein, Congress could grant federal courts jurisdiction over cases like this one involving frauds perpetrated upon or affecting postal service operations. He argued further that since there were no state laws providing remedies for such wrongs at the time of suit being filed (1883), it would be appropriate for Congress to provide them with federal remedy through granting jurisdictional power to federal courts.