United States v. Watkins 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 state prisoner. The case involved a man named William Watkins, who had been convicted of murder in the state of Georgia and sentenced to death. Watkins had filed a petition for a writ of habeas corpus in the federal court, claiming that his conviction was unconstitutional. The Supreme Court held that the federal court did not have the authority to issue a writ of habeas corpus to a state prisoner, as this was a matter that was within the jurisdiction of the state court. The Court reasoned that the writ of habeas corpus was a remedy that was available only to those who were in federal custody, and not to those who were in state custody. The Court also noted that the writ of habeas corpus was a remedy that was available only to those who were in federal custody, and not to those who were in state custody. The Court concluded that the federal court did not have the authority to issue a writ of habeas corpus to a state prisoner, and thus, Watkins' petition was denied.

In United States v. Watkins, the Supreme Court considered whether a witness could be compelled to testify before a grand jury about his involvement in an alleged conspiracy against the government. The majority held that he could not because it would violate his Fifth Amendment right against self-incrimination. Justice Field dissented from this opinion, arguing that while individuals have certain rights under the Constitution, they must also recognize their duty to assist in criminal investigations when called upon by proper authority and should not be allowed to use those same constitutional protections as shields for wrongdoing or obstruction of justice. He argued further that if witnesses were able to refuse testimony on such grounds then criminals would never be brought to justice and society's safety would suffer greatly as a result.