Moyer v. Dewey was a United States Supreme Court case that addressed the issue of whether a state governor had the authority to arrest and detain a person without a warrant. The case involved the arrest of Charles Moyer, a labor leader in Colorado, by Governor Jesse F. Dewey. Moyer had been arrested and detained without a warrant by the governor in response to a labor dispute. Moyer argued that the governor had violated his Fourth Amendment rights by arresting and detaining him without a warrant. The Supreme Court agreed with Moyer, ruling that the governor had acted outside of his authority in arresting and detaining Moyer without a warrant. The Court held that the governor had violated Moyer's Fourth Amendment rights and that the arrest and detention were unlawful. The Court's ruling in Moyer v. Dewey established that state governors do not have the authority to arrest and detain individuals without a warrant. The ruling also established that individuals have the right to be free from unreasonable searches and seizures, even when the search or seizure is conducted by a state governor.

In Moyer v. Dewey, the Supreme Court was tasked with determining whether a state governor had the authority to issue a warrant for arrest and detain an individual without due process of law. The majority opinion held that such power did not exist under the Constitution, but Justice Field dissented from this ruling. He argued that while it is true that no one can be deprived of their liberty without due process of law, there are certain instances in which exceptions must be made; namely when public safety or security is at stake. In his view, governors should have some degree of discretion to act quickly in order to protect citizens from harm or danger if they believe it necessary and appropriate given the circumstances. Furthermore, he asserted that any abuse of such power could easily be remedied by habeas corpus proceedings after-the-fact if needed - thus providing adequate protection against potential abuses while still allowing governors to take swift action when required for public safety reasons.