The fate of bump stocks in the U.S. is hanging on how the Bureau of Alcohol, Tobacco, Firearms, and Explosives answers a simple-sounding, but complex, question: What exactly is a machine gun?
The ATF started the process of finding an answer to that question last year, after the deadliest shooting in U.S. history unfolded in Las Vegas. There, a shooter is thought to have used bump stocks to speed up the rate of fire as he targeted a large concert crowd.
The agency has received more than 113,000 comments on how to proceed, and while the agency is now reviewing those comments behind closed doors, its decision will come down to how it decides to define the word “machine gun.”
If officials decide bump stocks are machine guns and can be regulated, they will then move on to considering exactly how to regulate them, a process that will require at least another round of comments and could stretch into next year or later.
But for now, the ATF’s first decision involves two laws: the National Firearms Act of 1934, the NFA, and the Gun Control Act of 1968, the GCA.
The NFA defines “machine gun” to be any weapon that “shoots, is designed to shoot, or can be readily restored to shoot automatically more than one shot, without manual reloading, by a single function of the trigger.” The word also covers “any part designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machine gun.”
A section of the GCA that passed in 1986 makes it illegal to possess a machine gun, with some exceptions, and uses the NFA’s definition of the word.
In a Federal Register notice released in December, the ATF said that in the last decade it has issued 10 letters in which it classified a variety of bump stocks to be unregulated parts or accessories, not machine guns. But that doesn’t mean the agency can’t reinterpret the law, and its December notice said it would look at whether to broaden the definition in the wake of the Las Vegas shooting.
“This [notice] is the initial step in a regulatory process to interpret the definition of machine gun to clarify whether certain bump stock devices fall within that definition,” the ATF wrote. “If, in a subsequent rulemaking, the definition of machine gun … is interpreted to include certain bump stock devices, ATF would then have a basis to re-examine its prior classification and rulings.”
In a hearing last year, then-ATF Acting Director Thomas Brandon indicated that the agency could define bump stocks as machine guns, or not as machine guns, depending on how they are built.
For example, in testimony before the Senate Judiciary Committee in December, Brandon noted that more than a decade ago, the ATF determined that some bump stocks were effectively machine guns because they were made in a way that allowed for multiple rounds to be fired with a single pull of a trigger.
“For instance, one device utilized springs to mechanically capture the recoil energy and re-engage the trigger,” he said in his prepared remarks. “ATF determined that such devices would constitute machine guns if those devices, once activated by a single pull of the trigger, would initiate an automatic firing cycle, which continued until either the finger is released or the ammunition supply is exhausted.”
He also noted that, later, the industry developed bump stocks that “did not include springs or similar components,” and said the ATF so far has left most of those unregulated.
“We have classified most of these to be firearm accessories that are not subject to NFA regulation, either because the devices shot only one bullet per pull of the trigger or because the devices did not appear to initiate a fully automatic firing cycle,” he said.
Brandon said the ATF was looking to see if federal law can be “interpreted to include these types of devices within the definition of machine gun.”
As Washington waits, President Trump on Monday made it clear that the answer he wants to see from the ATF is one that lets the government put them out of reach for gun users.
“Bump stocks, we are writing that out. I am writing that out,” he said from the White House. “I don’t care if Congress does it or not, I’m writing it out myself.”
