Shepherd v. Thompson was a United States Supreme Court case that addressed 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, Shepherd, was held in a federal prison in the state of Tennessee. Shepherd sought a writ of habeas corpus from the state court, claiming that he was being held in violation of the Constitution. 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 power to interfere with the federal government's authority to imprison individuals. The Court also noted that the writ of habeas corpus was a remedy that could only be used to challenge the legality of a person's detention, and not to challenge the conditions of the detention. The Court's decision in Shepherd v. Thompson 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 remains an important precedent in the area of federal-state relations.

Justice Field delivered the dissenting opinion in Shepherd v. Thompson, arguing that the majority had misapplied existing law to reach its decision. He argued that under prior Supreme Court precedent, a state court could not issue an injunction against a federal officer acting within his authority and jurisdiction as determined by Congress. The majority's ruling was contrary to this established principle of law because it allowed for such injunctions when they were issued pursuant to state statutes or common law rules rather than federal laws or regulations. Justice Field further noted that if states were permitted to enjoin federal officers from performing their duties, then there would be no uniformity among the states regarding how those officers should act and what powers they possess; thus creating chaos in our system of government where each state has different standards governing how federal officials must conduct themselves while carrying out their official duties. In conclusion, Justice Field believed that allowing states to enjoin federally authorized actions would lead only "to confusion and embarrassment" and urged the Court not to allow such action without explicit congressional authorization first being obtained.