In Montgomery v. Sawyer, the United States Supreme Court was asked to decide whether a state court had the authority to issue a writ of habeas corpus to a prisoner who had been convicted in a federal court. The petitioner, Montgomery, had been convicted in a federal court of a crime and sentenced to imprisonment. He then sought a writ of habeas corpus from the state court, claiming that his conviction was unconstitutional. The state court granted the writ and ordered Montgomery released from prison. 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 is a federal remedy, and that the state court did not have the power to interfere with a federal court's judgment. The Court further held that the state court's action was an unconstitutional interference with the federal court's judgment and that the writ of habeas corpus should not have been issued. The Court's decision in Montgomery v. Sawyer established that state courts do not have the authority to issue writs of habeas corpus to prisoners who have been convicted in federal courts. The decision also reaffirmed the principle that state courts cannot interfere with the judgments of federal courts.

Justice Field delivered the dissenting opinion in Montgomery v. Sawyer, arguing that the majority's decision was contrary to both law and equity. He argued that under California law, a contract between two parties could not be set aside on equitable grounds unless it had been obtained by fraud or undue influence. In this case, there was no evidence of either fraud or undue influence; rather, the contract had been entered into freely and voluntarily by both parties with full knowledge of its terms. Furthermore, Justice Field noted that even if one party were found to have acted inequitably in entering into a contract - which he did not believe to be true here - such inequity would only entitle them to damages for breach of contract rather than voiding the entire agreement as done by the majority opinion. As such, Justice Field concluded his dissent by stating that "the decree should have dismissed [the] bill."