Bloomberg Law
March 25, 2021, 8:37 PM

Federal Bump Stock Ban Blocked by Divided Appeals Court

Brian Flood
Brian Flood
Legal Reporter

The federal ban on bump stocks—devices that increase the rate of fire for semiautomatic weapons—is likely unlawful and must be put on hold, a divided Sixth Circuit said Thursday.

Bump stocks harness a gun’s recoil energy to rapidly move the firearm back and forth, bumping the shooter’s stationary finger against the trigger. In the wake of the 2017 Las Vegas mass shooting, in which a gunman using semiautomatic rifles with bump stocks killed 58 people, President Donald Trump ordered the Justice Department to quickly ban “all devices that turn legal weapons into machineguns.”

Federal law generally bans civilian ownership of machine guns manufactured after May 1986, including any parts used to convert an otherwise legal firearm into an illegal machine gun. It defines a machine gun as a weapon which fires “automatically more than one shot, without manual reloading, by a single function of the trigger.”

The Bureau of Alcohol, Tobacco, Firearms and Explosives issued a rule reinterpreting the terms “single function of the trigger” and “automatically” to ban bump stocks.

The group Gun Owners of America and others sued, claiming the rule violated the Administrative Procedure Act, the Fifth Amendment’s takings clause, and the 14th Amendment’s right to due process.

A lower court should have granted the plaintiffs’ request for a preliminary injunction against the rule, because they’ll likely be able to prove that the bump stock ban is unlawful, the U.S. Court of Appeals for the Sixth Circuit said.

Courts generally respect an administering agency’s reasonable interpretation of an ambiguous statute. But this Chevron deference “categorically does not apply to the judicial interpretation of statutes that criminalize conduct,” the court said. That applies to the machine gun ban, which carries criminal penalties, it said.

And the court disagreed with ATF’s interpretation of the law. “Single function of the trigger” refers to the mechanical process of the trigger, i.e. its depression, release, and resetting, the court said. A bump stock can’t be classified as a machine gun because it doesn’t enable a semiautomatic firearm to fire more than one shot each time the trigger goes through this cycle, the court added.

The majority opinion was written by Judge Alice M. Batchelder and joined by Judge Eric E. Murphy.

Judge Helene N. White dissented. The U.S. Supreme Court has applied Chevron in the criminal context in three binding decisions, including the landmark Chevron U.S.A. Inc. v. Natural Resources Defense Council Inc. itself, she said. And the ATF’s interpretation of the machine gun law as banning bump stocks is reasonable, White added.

Robert J. Olson of Vienna, Va. and Pentiuk, Couvreur & Kobiljak PC represent the plaintiffs.

The case is Gun Owners of Am. Inc. v. United States, 6th Cir., No. 19-01298, 3/25/21.

To contact the reporter on this story: Brian Flood in Washington at

To contact the editors responsible for this story: Rob Tricchinelli at; Nicholas Datlowe at