Mays v. Fritton 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, Mays, was held in a federal prison in the state of Missouri. Mays sought a writ of habeas corpus from the state court, claiming that he was being held in violation of his constitutional rights. The state court granted the writ, and the federal government appealed the decision to the Supreme Court. 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 a federal prison. The Court reasoned that the writ of habeas corpus was a federal remedy, and that the state court did not have the authority to interfere with the federal government's power to imprison individuals. The Court also noted that the state court's decision was in conflict with the federal government's exclusive power to imprison individuals. The Court's decision in Mays v. Fritton established that state courts do not have the authority to issue writs of habeas corpus to prisoners held in federal prisons. This decision has been cited in numerous subsequent cases, and it remains an important precedent in the area of federalism and the separation of powers.

In Mays v. Fritton, the United States Supreme Court was asked to determine whether a contract between two parties should be enforced despite one of the parties having been declared bankrupt prior to its execution. The majority opinion held that the contract could not be enforced because it would have violated bankruptcy laws and public policy. However, in dissent Justice Field argued that there was no legal basis for denying enforcement of this particular contract as it had been executed before either party became insolvent or bankrupt and did not violate any existing law at the time of its formation. He further noted that if such contracts were denied enforcement due to subsequent events beyond their control then all other contracts made by individuals who later become insolvent or bankrupt would also be subject to similar treatment which he believed would lead to great injustice and confusion in commercial transactions throughout society.