Hornbuckle v. Toombs 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 held in a federal prison. The case arose when a prisoner, Hornbuckle, was held in a federal prison in Georgia and sought a writ of habeas corpus from the state court. 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 the writ of habeas corpus. 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 state court should not be allowed to interfere with the federal government's power to protect this right. The Court's decision in Hornbuckle v. Toombs established 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 decision also established that the writ of habeas corpus was a fundamental right that the federal government had the power to protect.

In Hornbuckle v. Toombs, the Supreme Court was asked to decide whether a state court could issue an injunction against a federal officer in order to prevent him from executing his duties under federal law. The majority opinion held that such injunctions were not allowed and that the state court lacked jurisdiction over the matter. However, Justice Field dissented on this point, arguing that there is nothing in either the Constitution or any other law which prohibits states from issuing such injunctions when necessary for their own protection or when it does not interfere with any valid exercise of power by Congress. He argued further that if Congress had intended to limit states' ability to protect themselves through such measures they would have done so explicitly and clearly stated as much in its laws. As no such limitation exists, he concluded that states should be free to use whatever means are available within their borders for self-protection without fear of interference from federal officers acting pursuant to congressional authority