The complications to gun ownership started occurring soon after this. When gangster violence was seen as out of control, the laws needed to change to deter the overwhelming criminal activity involving guns. In 1939, the law was challenged in connection with the Second Amendment right to keep and bear arms in Miller v. United States.

The matter at hand involved travelling across state lines with a sawed-off, 12-gauge, double barrel shotgun that was deemed unlawful under the NFA. The Supreme Court was unanimous in their decision that the NFA’s limitations on weapons did not violate the Second Amendment and the explained that a shortened shotgun did not present…

“some reasonable relationship to the preservation or efficiency of a well-regulated militia. We cannot say that the Second Amendment guarantees the right to keep and bear such an instrument”

To add controversy to this issue, the fact that sawed-off shotguns had been in use by the U.S. military in the trenches of WWI was often brought up in defense of this right to bear arms.