The Supreme Court’s conservative supermajority carved a huge loophole into the federal prohibition against machine guns on Friday, striking down a bump stock ban first enacted in 2018 by the Trump administration. Its 6–3 decision allows civilians to convert AR-15–style rifles into automatic weapons that can fire at a rate of 400–800 rounds per minute. One might hope a ruling that stands to inflict so much carnage would, at least, be indisputably compelled by law. It is not.

The Supreme Court’s decision invalidating the nationwide bump stock ban ignited a firestorm among Democrats and gun control groups that have long maligned the device used to perpetrate the nation’s deadliest mass shooting. 

The groups expressed worry about not only the impacts of lifting the ban, which could trigger a booming rapid-fire marketplace, but also the other gun cases that remain pending on the justices’ docket. 

The Supreme Court has struck down the reclassification of bump stocks that was promulgated by the Trump administration back in 2018. As I noted earlier this year, this was not a Second Amendment case, but a statutory case, and, as such, the question was not whether bump stocks count as “arms,” but whether the National Firearms Act of 1934 grants the executive branch the power to regulate them in the same manner as it regulates machine guns. As the Court makes clear, the answer to this is unquestionably no. In consequence, the regulation must fall.