United States v. Miller involved a criminal prosecution under the National Firearms Act of 1934 (NFA). Passed in response to public outcry over the St. Valentine's Day Massacre, the NFA requires certain types of firearms (including but not limited to fully automatic firearms and short-barreled rifles and shotguns) to be registered with the Miscellaneous Tax Unit (later to be folded into what eventually became the Bureau of Alcohol, Tobacco, Firearms, and Explosives, or ATF) which at the time was part of the Bureau of Internal Revenue (ancestor of today's Internal Revenue Service), with a $200 tax paid at the time of registration and again if the firearm was ever sold.
Defendants Miller and Layton filed a demurrer challenging the relevant section of the National Firearms Act as an unconstitutional violation of the Second Amendment. District Court Justice Heartsill Ragon accepted the claim and dismissed the indictment, stating, "The court is of the opinion that this section is invalid in that it violates the Second Amendment to the Constitution of the United States, U.S.C.A., providing, 'A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.'" Justice Ragon provided no further explanation of his reasons.
Neither the defendants nor their legal counsel appeared at the Supreme Court. A lack of financial support and procedural irregularities prevented counsel from traveling. Miller was found shot to death in April, before the decision was rendered.
United States v. Miller