Bump Stocks: Unpacking The Controversy After Supreme Court Lifts Ban

 The Supreme Court struck down a Trump-era ban on “bump stocks” for guns on Friday—devices that allow a semi-automatic rifle to fire shots rapidly, mimicking a machine gun—reviving a years-old controversy over the devices after they first came under scrutiny following the 2017 Las Vegas mass shooting.

June 7, 2010In a letter to bump stock manufacturer Slide Fire Solutions, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) confirms it’s evaluated the company’s bump stocks and determined they are regulated as a firearm part, not a machine gun—which would make them illegal under federal law.

October 1, 2017A gunman opens fire at the Route 91 Harvest Festival in Las Vegas using a firearm equipped with a bump stock, killing 60 people and injuring more than 400—the deadliest shooting in modern U.S. history.

October 5, 2017Amid calls from lawmakers to regulate the devices—including some Republicans—the National Rifle Association issues a statement saying it believes bump stocks “should be subject to additional regulations” (it has since backed overturning the ban).

October 10, 2017A bipartisan group of lawmakers introduce legislation to ban the devices, but a day later, then-House Speaker Paul Ryan, R-Wis., urges the government to restrict bump stocks using regulations instead.

December 26, 2017The ATF publishes a proposed rule that would reclassify bump stocks as machine guns, which would ban them under federal law.

February 20, 2018Then-President Donald Trump issues a memorandum calling on the Justice Department to “dedicate all available resources” to reviewing comments on the proposed rule and coming up with a final proposal to ban bump stocks.

December 18, 2018The Justice Department announces its final rule banning bump stocks through the ATF, saying it’s “faithfully following President Trump’s leadership by making clear that bump stocks, which turn semiautomatics into machine guns, are illegal.”

March 26, 2019The final rule banning bump stocks takes effect, with all bump stock owners having to either destroy their bump stocks by that date or turn them into the ATF—and gun owner Michael Cargill immediately files a federal lawsuit challenging the ban.

November 23, 2020A federal district judge rules against Cargill.

January 6, 2023A federal appeals court strikes down the bump stock ban, after several other appeals court rulings upheld it—leading the dispute to make its way to the Supreme Court.

June 14, 2024The Supreme Court rules 6-3 that the ATF exceeded its authority when it banned bump stocks, striking down the federal rule.

Bump stocks are devices that are added to semi-automatic firearms, replacing the stock of the gun with a sliding stock and trigger guard. When the shooter pulls the trigger, the recoil of the gun, together with the sliding stock, repeatedly “bump” the shooter’s finger against the trigger at a high speed, meaning they can fire shots much faster than with a traditional semi-automatic weapon. The devices were long allowed under federal law—and the Supreme Court said Friday the ATF couldn’t ban them—because the federal definition for a “machine gun” is a firearm that can shoot “automatically more than one shot, without manual reloading, by a single function of the trigger.” Bump stocks, by contrast, technically require the trigger to be deployed multiple times, just at a higher speed.

It remains to be seen if Congress could try to ban bump stocks itself now that the federal rule will be struck down—and if any Republicans will get behind restricting the devices, as some did in 2017. Conservative-leaning Justice Samuel Alito called on lawmakers to take action against bump stocks in a concurring opinion Friday, writing that Congress amending federal law would be a “simple remedy” for bump stocks not being classified as machine guns. “Congress can amend the law—and perhaps would have done so already if ATF had stuck with its earlier interpretation,” Alito wrote. “Now that the situation is clear, Congress can act.”

“Congress’s definition of ‘machinegun’ encompasses bump stocks just as naturally as [automatic weapons] M16s,” Justice Sonia Sotomayor wrote in a dissenting opinion Friday, joined by Justices Elena Kagan and Ketanji Brown Jackson. “Just like a person can shoot ‘automatically more than one shot’ with an M16 through a ‘single function of the trigger’ if he maintains continuous backward pressure on the trigger, he can do the same with a bump-stock-equipped semiautomatic rifle if he maintains forward pressure on the gun. Today’s decision to reject that ordinary understanding will have deadly consequences.”


Bump stock manufacturers claimed to the ATF that their devices were intended for people with disabilities who might otherwise have trouble shooting a gun, with the federal agency noting in its 2010 letter that Slide Fire Solutions said its product was “intended to assist persons whose hands have limited mobility.” Slide Fire inventor Jeremiah Cottle told specialist gun publications otherwise, however, noting in a 2016 interview with Ammoland that his bump stocks are intended for “people, like me, [who] love full auto.”

The bipartisan effort to restrict bump stocks was a rare significant government action in restricting firearms in recent years, as gun control legislation and other government efforts on guns have become stymied by Republican opposition despite high-profile mass shootings. The Supreme Court’s decision to drop the bump stock ban comes after justices issued a significant ruling in 2022 that made it easier to challenge gun regulations, striking down New York’s concealed carry law and ruling the Second Amendment includes the right to “[carry] handguns publicly for self-defense.” Garland v. Cargill was one of two major gun-rights cases that the Supreme Court heard this term, along with a case challenging the prohibition on people with restraining orders for domestic abuse possessing firearms. The court has not yet ruled in that case.