The Dayton shooter modified his gun with a ‘pistol brace,’ a device that could become the new bump stock of the gun-control debate

Dayton Police Department handout via Reuters.

A device used in Sunday’s deadly shooting in Dayton, Ohio, could spur a new debate over guns and how some owners are modifying them.
The shooter used an AR-15-style pistol outfitted with the pistol brace to kill nine people and injure 27, ultimately firing at least 41 shots in roughly 30 seconds.
The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has issued a number of conflicting rulings in recent years on pistol braces and how they can be legally used.
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The gunman in Dayton, Ohio, killed nine people and injured 27 using a .223 caliber AR-15-style pistol he had "modified, in essence, to function like a rifle."

Dayton Police Chief Richard Biehl told reporters that the gunman had outfitted his legally purchased pistol with a drum magazine that could hold 100 rounds, and with a "pistol brace" to improve stability.

In total, he fired at least 41 shots in roughly 30 seconds using his weapon.

The gun’s modifications have already prompted some curiosity over the device that may have helped the gunman aim better or heighten his control over the weapon.

It’s unclear whether the braces will meet the same fate as bump stocks, which were recently banned after they were used in the 2017 Las Vegas massacre, but it’s possible they’ll spark a similar debate.

Dayton Police Department handout via Reuters

Pistol braces, also known as blades or stabilizing braces, claim to "enhance accuracy and reduce felt recoil when using an AR-style pistol," according to the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

Pistol braces and the minute details of their designs have been subject to debate even within the ATF, which issued a series of conflicting directives on the matter in 2012, 2015, and 2017.

The devices help shooters ‘fire a pistol with rifle-like accuracy’

At issue is whether the pistol brace essentially converts a pistol into a short-barreled rifle, which would make the weapons subject to a series of onerous federal restrictions, including paying for a $200 tax stamp and awaiting approval from the ATF.

The ATF originally ruled in 2012 that since the pistol brace attached to the shooter’s forearm and was used to help stabilize the weapon, it was fine to use because it didn’t turn the pistol into a short-barreled rifle.

Julie Carr Smyth/AP

But in the following years, the ATF went back and forth over how to regulate such instances where pistol braces were used not on the forearms, but held against shooters’ shoulders like shoulder stocks.

In 2015, the agency said the devices used like shoulder stocks would, indeed, turn pistols into short-barreled rifles. But in 2017, it ruled that the devices could still be fired from the shoulder without being classified as a short-barreled rifle so long as the shooter didn’t take "affirmative steps to configure the device for use as a shoulder-stock," such as removing the arm strap.

Some gun-control advocates took issue with this interpretation, arguing that the braces and similar devices merely helped gun owners skirt the law.

The Giffords Law Center to Prevent Gun Violence warned in September 2018 that pistol braces allow shooters "to fire a pistol with rifle-like accuracy," and slammed the ATF for its 2017 ruling.

"ATF’s decision clearly fails to address the significant public safety threat posted by these pistol arm braces," the center wrote.