Walker v. Henshaw 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 federal custody. The case arose when a prisoner, Walker, was held in federal custody in the state of Georgia. Walker sought a writ of habeas corpus from the state court, which the court granted. The federal government then 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 federal custody. The Court reasoned that the writ of habeas corpus was a federal prerogative and that the state court did not have the authority to interfere with the federal government's power to detain a prisoner. 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 the rights of its citizens. 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 was a federal prerogative and that the state court did not have the authority to interfere with the federal government's power to detain a prisoner. 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 the rights of its citizens.

In Walker v. Henshaw, the Supreme Court was asked to decide whether a state court had jurisdiction over an action brought by a citizen of one state against another in which the defendant resided in yet another state. The majority opinion held that it did not have such jurisdiction and 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 exclusive power to regulate cases between citizens of different states; secondly, he asserted that even if Congress had not exercised its authority in this matter then each individual State should be allowed to exercise their own discretion as they saw fit when deciding matters involving citizens from other States. In conclusion, Justice Field believed that either way there was no reason for denying jurisdiction to State courts and thus urged his colleagues on the bench to reverse their ruling and allow for litigation between parties residing in different states within those respective jurisdictions.