From today's statement by Justice Thomas in Harrel v. Raoul:
The State of Illinois enacted a law that makes it a felony to possess what Illinois branded "assault weapons," a term defined to include AR–15s. "The AR–15 is the most popular semi-automatic rifle" in America and is therefore undeniably "in common use today." Petitioners sought a preliminary injunction against the enforcement of the law, arguing that the law violates their Second Amendment right to "keep and bear Arms." The Court of Appeals for the Seventh Circuit rejected petitioners' request for a preliminary injunction, concluding "that the AR–15 … is not protected by the Second Amendment." According to the Seventh Circuit, the rifle selected by millions of Americans for self-defense and other lawful purposes does not even fall within the scope of the Arms referred to by the Second Amendment.
This Court is rightly wary of taking cases in an interlocutory posture. But, I hope we will consider the important issues presented by these petitions after the cases reach final judgment.
We have never squarely addressed what types of weapons are "Arms" protected by the Second Amendment. To be sure, we explained in District of Columbia v. Heller (2008), that the Second Amendment's protection "extends, prima facie, to all instruments that constitute bearable arms, even those that were not in existence at the time of the founding." And, we noted that "the Second Amendment does not protect those weapons not typically possessed by law-abiding citizens for lawful purposes," recognizing "the historical tradition of prohibiting the carrying of dangerous and unusual weapons." But, this minimal guidance is far from a comprehensive framework for evaluating restrictions on types of weapons, and it leaves open essential questions such as what makes a weapon "bearable," "dangerous," or "unusual."