Massachusetts law criminalizing possession of a stun gun violates the Second Amendment. When Caetano’s abusive ex-boyfriend approached her as she left work and started yelling at her, she pulled out a stun gun and said “I’m not gunna take this anymore . . . . I don’t wanna have to [use this on] you, but if you don’t leave me alone, I’m gonna have to.” The gambit worked and the ex-boyfriend left. However, after police discovered the stun gun during an unrelated investigation, Caetano was convicted under a Massachusetts law that prohibited possession of stun guns. The Massachusetts Supreme Court affirmed the judgment and upheld the law based on its conclusion that a stun gun was not the type of weapon that is eligible for Second Amendment protection. In a per curiam opinion, the United States Supreme Court vacated the judgment and remanded the case. In District of Columbia v. Heller (2008) 554 U.S. 570, 582, the Court 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.” The Massachusetts Supreme Court concluded that stun guns are not protected because they were not in common use at the time of the Second Amendment’s enactment, are “unusual,” and are not “readily adaptable to use in the military.” The court’s conclusion and reasoning are inconsistent with Heller. Accordingly, the Massachusetts Supreme Court erred by concluding that a stun gun did not qualify for Second Amendment protection.

The full opinion is available on the court’s website here: http://www.supremecourt.gov/opinions/15pdf/14-10078_aplc.pdf