Sawyer v. Weaver was a United States Supreme Court case that dealt with the issue of whether a state court could issue a writ of habeas corpus to a prisoner held in federal custody. The case arose when the petitioner, William Sawyer, was convicted of murder in the state of Georgia and sentenced to death. Sawyer sought a writ of habeas corpus from the state court, claiming that his conviction was unconstitutional. The state court granted the writ, and Sawyer was released from federal custody. The United States Supreme Court held that the state court did not have the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The Court reasoned that the writ of habeas corpus is a federal remedy, and that the state court did not have the power to interfere with the federal government's authority to detain a prisoner. The Court also noted that the writ of habeas corpus is a remedy that is available only to those who are in custody in violation of the Constitution or laws of the United States. In conclusion, the Supreme Court held that the state court did not have the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The Court reasoned that the writ of habeas corpus is a federal remedy, and that the state court did not have the power to interfere with the federal government's authority to detain a prisoner.

In Sawyer v. Weaver, the Supreme Court was asked to decide whether a state court had jurisdiction over an action brought by a non-resident against another non-resident in which both parties were citizens of different states. The majority opinion held that the state court did not have jurisdiction and thus dismissed the case. However, Justice Field dissented from this decision on two grounds: firstly, he argued that under Article III of the Constitution, Congress has given federal courts exclusive original jurisdiction only over certain types of cases; secondly, he argued that even if Congress had intended for such suits to be heard exclusively in federal courts it would still be unconstitutional as it would deny individuals their right to access justice through their own local courts. He concluded by noting that while there may be some instances where allowing such suits in state courts could lead to confusion or conflict between them and federal ones, these issues can easily be addressed without denying individuals access to justice through their local judicial systems.