United States v. McKee is a United States Supreme Court case that dealt with the issue of whether a federal court had the authority to issue a writ of habeas corpus to a prisoner held in a state prison. The case involved a prisoner, William McKee, who was convicted of murder in the state of Pennsylvania and sentenced to life in prison. McKee filed a petition for a writ of habeas corpus in the federal court, claiming that his conviction was unconstitutional. The federal court granted the writ and ordered McKee's release from prison. The United States Supreme Court reversed the decision of the federal court, ruling that the federal court did not have the authority to issue a writ of habeas corpus to a prisoner held in a state prison. The Court held that the writ of habeas corpus was a remedy available only to prisoners held in federal custody, and that the federal court did not have the authority to interfere with the state court's decision. The Court also noted that the writ of habeas corpus was not intended to be used as a means of overturning state court decisions.

In United States v. McKee, the Supreme Court was tasked with determining whether a federal statute that allowed for the forfeiture of goods imported in violation of law applied to certain merchandise seized by customs officers from a vessel owned by William McKee. The majority opinion held that it did apply and thus affirmed the lower court's decision ordering forfeiture of the goods. In his dissenting opinion, Justice Field argued that since there was no proof presented at trial showing any intent on behalf of Mr. McKee to violate any laws or regulations governing importation into this country, he should not be subject to such severe penalties as those imposed through forfeitures under this particular statute. He further noted that if Congress intended for these types of forfeitures to occur without regard for culpability or knowledge on behalf of an owner then they would have included language in their legislation making clear such an intention existed; however, no such language is present in this case and therefore it cannot be assumed Congress meant otherwise when passing this law.