Walden v. Knevals 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 another state. The case arose when a prisoner, Walden, was held in a prison in the state of Georgia, but was being held on a writ of habeas corpus issued by a court in the state of Alabama. Walden argued that the writ was invalid because it was issued by a court in a different state. The Supreme Court held that the writ was valid, and that the state court had the authority to issue it. The Court reasoned that the writ was issued in accordance with the Full Faith and Credit Clause of the United States Constitution, which requires states to give full faith and credit to the judicial proceedings of other states. The Court also noted that the writ was issued in accordance with the Extradition Clause of the Constitution, which allows for the extradition of persons from one state to another. The Court's decision in Walden v. Knevals established that state courts have the authority to issue writs of habeas corpus to prisoners held in other states. This decision has been cited in numerous subsequent cases, and has been used to support the idea that state courts have the authority to issue writs of habeas corpus to prisoners held in other states.

Justice Field delivered the dissenting opinion in Walden v. Knevals, arguing that the majority had misapplied the law and failed to consider important evidence presented by both parties. He argued that there was sufficient evidence to show that a contract existed between the two parties, which would have allowed for recovery of damages from Knevals as per their agreement. Furthermore, he noted that even if no contract did exist between them, it could still be inferred from their actions and correspondence with one another. As such, Justice Field concluded that Walden should have been granted relief on either basis and thus disagreed with the majority's ruling denying him any compensation or damages from Knevals.