Supreme Court invalidates Trump-era bump stock ban 

The Supreme Court invalidated the Trump-era prohibition on bump stocks along ideological lines Friday, ending the nationwide ban on the devices, which convert semi-automatic weapons to ones capable of firing hundreds of rounds per minute.

The Biden administration defended the regulation in front of the high court after the Trump administration first implemented it in the wake of the 2017 Las Vegas mass shooting, the deadliest in U.S. history. The shooter had used guns equipped with a bump stock to kill 60 people and wound hundreds of others.

Both the Trump and Biden administrations have since made possessing the devices a criminal offense by having the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) newly classify them as machine guns under long-standing federal law.  The case did not implicate the Second Amendment.

In a 6-3 decision authored by conservative Justice Clarence Thomas, the court said the ATF stretched the law too far, ruling in favor of the challenger. 

“We conclude that a semiautomatic rifle equipped with a bump stock is not a ‘machinegun’ because it does not fire more than one shot ‘by a single function of the trigger,’” Thomas wrote, quoting the statutory definition.

Conservative Justice Samuel Alito, who joined Thomas’s opinion, also wrote separately to stress there is a “simple remedy” that would allow a nationwide ban on bump stocks. 

“Congress can amend the law — and perhaps would have done so already if ATF had stuck with its earlier interpretation. Now that the situation is clear, Congress can act,” Alito wrote. 

Michael Cargill, an Austin-based gun store owner, challenged the bump stock ban after surrendering two in 2019. He was backed by the National Rifle Association and other major gun advocacy groups.

“Over five years ago I swore I would defend the Constitution of the United States, even if I was the only plaintiff in the case. I did just that,” Cargill said in a statement.

The court’s three liberals dissented in an opinion authored by Justice Sonia Sotomayor, who read her dissent from the bench, a rarity underscoring how the court viewed the importance of the case.

“When I see a bird that walks like a duck, swims like a duck, and quacks like a duck, I call that bird a duck. A bump-stock-equipped semiautomatic rifle fires ‘automatically more than one shot, without manual reloading, by a single function of the trigger,’” Sotomayor wrote. 

“Because I, like Congress, call that a machinegun, I respectfully dissent.” 

In the coming days, the Supreme Court is set to hand down another closely watched gun case that does implicate the Second Amendment: The justices are weighing whether a federal statute criminalizing gun possession for people under domestic violence restraining orders is constitutional.

Updated 10:47 a.m. ET