Pound v. Turck was a United States Supreme Court case that dealt with the issue of whether a state court had the authority to issue a writ of habeas corpus to a prisoner who was being held in a federal prison. The case arose when a prisoner, William Pound, was held in a federal prison in Wisconsin. Pound sought a writ of habeas corpus from the Wisconsin state court, claiming that he was being held in violation of the Constitution. The federal government argued that the state court did not have the authority to issue the writ, as the federal government had exclusive jurisdiction over the prison. The Supreme Court ultimately held that the state court did not have the authority to issue the writ of habeas corpus. The Court reasoned that the federal government had exclusive jurisdiction over the prison, and thus the state court did not have the authority to interfere with the federal government's authority. The Court also noted that the writ of habeas corpus was a federal remedy, and thus the state court did not have the authority to issue it. As a result, the Court held that the state court did not have the authority to issue the writ of habeas corpus to Pound.

In the case of Pound v. Turck, the Supreme Court was asked to determine whether a Wisconsin statute that allowed for an appeal from a justice court's judgment in certain cases was constitutional. The majority opinion held that it was not, as it violated Article III of the Constitution which states that only federal courts can have appellate jurisdiction over state courts. Justice Field dissented and argued that while Article III does limit Congress' power to create appeals from state court judgments, this limitation did not extend to individual states who could choose how they wanted their own judicial systems structured. He further noted that since there were no other laws prohibiting such appeals at the time of passage, Wisconsin had every right to pass its own law allowing them and thus should be upheld by the Court.