Caetano v. Massachusetts, 577 U.S. ___, 136 S. Ct. 1027 (Mar. 21, 2016)

The Court vacated and remanded the decision of the Supreme Judicial Court of Massachusetts, finding that court erred in interpreting District of Columbia v. Heller, 554 U. S. 570 (2008), to hold that the Second Amendment does not extend to stun guns. The Court began by noting that Heller held "the Second Amendment extends, prima facie, to all instruments that constitute bearable arms, even those that were not in existence at the time of the founding."