In the United States v. Miller et al., 1938, Jack Miller and Frank Layton were charged with transporting an unregistered sawed-off shotgun across state lines, in violation of the National Firearms Act of 1934. They argued that this act violated their Second Amendment right to keep and bear arms. The District Court agreed with them, but on appeal by the government, the Supreme Court reversed this decision. The Supreme Court held that because a sawed-off shotgun has not been shown to be part of ordinary military equipment or contribute to maintaining an effective well-regulated militia as described in the Second Amendment, its possession does not fall under constitutional protection. Therefore, it ruled that Congress could regulate such weapons without violating individuals' rights.

In the United States v. Miller et al., 1938, there was no recorded dissenting opinion. The Supreme Court unanimously ruled that the Second Amendment does not guarantee an individual's right to own a firearm unrelated to service in a well-regulated militia. This decision upheld federal restrictions on firearms under the National Firearms Act of 1934, which regulated and taxed certain types of guns and equipment often associated with organized crime such as sawed-off shotguns or machine guns. The court reasoned that these weapons had no reasonable relationship to the preservation or efficiency of a "well-regulated militia."