Leathers v. Blessing 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, Leathers, was held in a federal prison in the state of Missouri. Leathers 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 Leathers was released from prison. The federal government then appealed the decision to the Supreme Court, arguing 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 Supreme Court agreed with the federal government, ruling 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 power, 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 writ of habeas corpus was a fundamental right, and that the federal government had the power to protect that right.

In Leathers v. Blessing, the United States Supreme Court was tasked with determining whether a judgment rendered in favor of a plaintiff by an Ohio state court could be enforced against property located outside of the state. The majority opinion held that it could not, as such enforcement would violate the Full Faith and Credit Clause of Article IV of the Constitution. Justice Field dissented from this ruling on two grounds: firstly, he argued that since there was no conflict between Ohio law and any other jurisdiction's laws regarding judgments being enforceable against out-of-state property, there should have been no issue enforcing it; secondly, he noted that even if there were some potential conflict between jurisdictions' laws concerning this matter - which he did not believe to be true - then under Section 1 of Article IV Congress had already provided for how conflicts like these should be resolved. As such, Justice Field concluded that enforcing the judgment in question would not have violated either federal or state law and thus should have been allowed to stand.