On Monday, in Caetano v. Massachusetts, the Supreme Court issued a per curiam opinion vacating the Supreme Judicial Court of Massachusetts’s holding that stun guns are not protected under the Second Amendment. Justice Samuel Alito authored a rather biting concurrence, which Justice Clarence Thomas joined.

The case came about after Caetano, a petite woman, obtained a stun gun to protect herself from her abusive ex-boyfriend who had previously hospitalized her, and who was undeterred by the multiple restraining orders she had obtained against him.  One evening Caetano found her abusive ex waiting for her outside her place of employment. When he began shouting and acting aggressively, Caetano threatened him with the stun gun. Although the restraining orders did not frighten him, the stun gun did, and he left. 

Later on, however, Caetano’s stun gun was discovered by police, and she was prosecuted for violating Massachusetts’s ban.  (The statute banning stun guns states, “No person shall possess a portable device or weapon from which an electrical current, impulse, wave or beam may be directed, which current, impulse, wave or beam is designed to incapacitate temporarily, injure or kill.”  Mass. Gen. Laws Ann. ch. 140, § 131J.)

The Supreme Judicial Court of Massachusetts provided three reasons why stun guns are unprotected by the Second Amendment, each of which the Supreme Court’s per curiam opinion and Justice Alito’s concurring opinion rejected based on the Court’s precedent set in District of Columbia v. Heller. (Heller was the Court’s self-described “first in-depth examination of the Second Amendment,” which held three District of Columbia ordinances unconstitutional, including a ban on handguns.)

1. The Supreme Judicial Court of Massachusetts held that the Second Amendment does not extend to stun guns because “stun guns were not in common use at the time of the Second Amendment's enactment.”

The Supreme Court found this reasoning to be “inconsistent with Heller's clear statement that the Second Amendment “extends ... to ... arms ... that were not in existence at the time of the founding.”

Justice Alito stated that “In Heller, we emphatically rejected such a formulation. We found the argument ‘that only those arms in existence in the 18th century are protected by the Second Amendment’ not merely wrong, but ‘bordering on the frivolous.’”Justice Alito elaborated, “Electronic stun guns are no more exempt from the Second Amendment's protections, simply because they were unknown to the First Congress, than electronic communications are exempt from the First Amendment, or electronic imaging devices are exempt from the Fourth Amendment.” He then pointed out that Heller “held that ‘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.’”

2. The Supreme Judicial Court of Massachusetts then justified the constitutionality of the ban by holding that stun guns are dangerous and unusual weapons (which under Heller are unprotected by the Second Amendment).  The court reasoned that stun guns are dangerous because they are constructed for the purpose of bodily assault or defense, and unusual because they were “not in common use at the time of enactment” and because “the number of Tasers and stun guns is dwarfed by the number of firearms.”

The Supreme Court simply rejected this reasoning by reiterating that “equating ‘unusual’ with ‘in common use at the time of the Second Amendment’s enactment’…is inconsistent with Heller.”The Court did not address the Massachusetts court’s dangerousness analysis, reinforcing that a weapon must be both dangerous and unusual to fall outside the scope of the Second Amendment.

Justice Alito took a more straight forward approach, explaining that, “As the per curiam opinion recognizes, this is a conjunctive test: A weapon may not be banned unless it is both dangerous and unusual.”  He then stated that “the relative dangerousness of a weapon is irrelevant when the weapon belongs to a class of arms commonly used for lawful purposes,” and that “if Heller tells us anything, it is that firearms cannot be categorically prohibited just because they are dangerous.”  Addressing the Massachusetts court’s ruling that stun guns are unusual because they are less popular than firearms, Justice Alito determined it was “beside the point” because otherwise all weapons except handguns (deemed by Heller to be the most popular self-defense weapon) could be banned.  Elaborating, Justice Alito added, “While less popular than handguns, stun guns are widely owned and accepted as a legitimate means of self-defense across the country. Massachusetts' categorical ban of such weapons therefore violates the Second Amendment.”

3. Lastly, the Supreme Judicial Court of Massachusetts determined that the Second Amendment does not apply to stun guns because “they are not readily adaptable to use in the military” and therefore not a “weapon of warfare to be used by the militia.”

The Supreme Court dismissed this reasoning as contradictory to Heller, which “rejected the proposition ‘that only those weapons useful in warfare are protected.’”

Justice Alito added that “Heller actually said that it would be a ‘startling reading’ of [U.S. v. Miller] to conclude that ‘only those weapons useful in warfare are protected.’”

While Caetano did not cover new ground, instead reinforcing already-existing precedent set by Heller, rights proponents may feel encouraged for a number of reasons.

First, Caetano seems to demonstrate that the post-Scalia Court recognizes Heller as settled precedent, and indicates that Heller may not be in danger of being overturned, as many had feared. (Of course, this is not to say that the liberals on the Court would not vote to overturn Heller if they knew they had the votes.)

Second, a clear recognition by the Court that a “dangerous and unusual” analysis requires two distinct analyses will help to prevent lower court errors in the future.

Third, the per curiam opinion, and especially the concurring opinion, strongly reject the rationale that was used in Friedman v. City of Highland Park, in which the Seventh Circuit upheld so-called “large-capacity magazine” and “assault weapon” bans.  Highland Park applied a three-part test, which questioned “whether a regulation bans weapons that were common at the time of ratification or those that have some reasonable relationship to the preservation or efficiency of a well regulated militia, and whether law-abiding citizens retain adequate means of self-defense.” Caetano’s per curiam opinion rejected the “common at the time of ratification” and “reasonable relationship to the militia” tests for contradicting Heller. The concurrence rejected the “alternative arms” part of the test, explaining that under Heller, “the right to bear other weapons is ‘no answer’ to a ban on the possession of protected arms.” Some viewed the Court’s denial of certiorari in Highland Park as some sort of grant of approval, but clearly, that was not the case. 

Fourth, Justice Alito’s concurrence adds support to Heller’s holding that complete bans on Second Amendment arms are categorically unconstitutional.

Fifth, Justice Alito, who delivered the opinion of the Court in McDonald v. City of Chicago, (the Court’s only other landmark Second Amendment case aside from Heller, in which the Court held that the Second Amendment applies to the States) had been notably absent from recent dissents from denials of certiorari in high profile Second Amendment cases.  His strong defense of Heller in Caetano should be reassuring for rights proponents.

Sixth, Caetano demonstrates the remarkable breadth of Heller. Although Heller explained that as “the first in-depth examination of the Second Amendment, one should not expect it to clarify the entire field,” it is becoming apparent that if applied properly, Heller can resolve the vast majority of Second Amendment issues that post-Heller courts have considered thus far.    

It should be intriguing to track Caetano as it returns to the Supreme Judicial Court of Massachusetts. Particularly, assuming the court determines stun guns are protected by the Second Amendment, it will be interesting to see whether the court applies the Second Amendment differently outside the home, or to a homeless person living out of a hotel.