WASHINGTON — Some Supreme Court justices on Wednesday expressed reluctance to strike down a ban on "bump stocks," a gun accessory that allows semi-automatic rifles to fire more quickly, although the final outcome remains unclear.
The prohibition was imposed by the Trump administration after the Las Vegas mass shooting in 2017 in which Stephen Paddock used bump stock-equipped firearms to open fire on a country music festival, initially killing 58 people.
The Supreme Court in 2019 declined to block the regulation. The already conservative court has tilted further to the right since then, with conservative Justice Amy Coney Barrett, a Trump appointee, replacing liberal Justice Ruth Bader Ginsburg, who died in 2020.
Conservatives now have a 6-3 majority that has backed gun rights in previous cases.
During oral arguments, both conservative and liberal justices asked questions indicating that they believe it's plausible that an almost 100-year-old law aimed at banning machine guns could be interpreted to include bump stocks. Whether there is a majority that reaches that conclusion remains to be seen.
The National Firearms Act was enacted in 1934 to regulate machine guns in response to prohibition-era gangster violence.
Liberal Justice Elena Kagan appeared incredulous that a weapon that can fire "a torrent of bullets" could not be defined as a machine gun.
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"This in the heartland of what they were concerned about," she said, referring to Congress. The court's two other liberal justices, Sonia Sotomayor and Ketanji Brown Jackson, appeared to share Kagan's views.
Barrett told Brian Fletcher, the Biden administration lawyer defending the ban, that she was "entirely sympathetic to your argument."
But at other points, she and other conservatives seemed more receptive to arguments made by a lawyer for Texas-based gun owner and licensed dealer Michael Cargill, who owned two bump stocks before the ban went into effect and later surrendered them to the government.
Barrett said that if Congress meant to include accessories like bump stocks that had not been invented at the time of the initial regulation, like bump stocks, it could have written it more clearly.
Justice Neil Gorsuch, while saying he could "understand why these items should be made illegal," questioned whether the statute could be interpreted to include bump stocks.
He expressed sympathy for gun owners who had previously been told by the ATF that bump stocks were lawful before it changed course after the Las Vegas shooting.
Justice Brett Kavanaugh, another conservative, made similar remarks.
"It's not dispositive, but it's a reason for pause," he said.
Chief Justice John Roberts, like Kavanaugh a potential key vote if the court is divided, said little to indicate which way he was leaning.
In his lawsuit, Cargill claimed that the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) lacked the legal authority to implement the prohibition.
Bump stocks use the recoil energy of a trigger pull to enable the user to fire up to hundreds of rounds with what the federal government calls "a single motion."
Cargill's lawyers say it is a difficult skill to master.
Some gun rights advocates, including the National Rifle Association, initially backed Trump's move to regulate bump stocks after the Las Vegas shooting but have since lined up in opposition to it.
The case does not implicate the scope of the right to bear arms under the Constitution's Second Amendment. The challengers argue that the government does not have the authority to ban bump stocks under the 1934 law.
The 1968 Gun Control Act defined "machine gun" to include accessories "for use in converting a weapon" into a machine gun, and the ATF concluded that bump stocks meet that definition.
Much of the debate during the oral argument focused on the legal definition of machine gun as a weapon that can automatically fire more than one shot "by a single function of the trigger."
The government argues that the phrase refers to the actions of the shooter, with a single action required to fire multiple shots. Cargill's lawyers argue that it refers to the action inside the firearm when the trigger is engaged. Because a bump stock still requires the trigger to be engaged for each shot, it is not a machine gun, they argue.
Kavanaugh pressed Cargill's lawyer, Jonathan Mitchell, on that issue, questioning whether there was any evidence that when Congress wrote the statute the phrase "function of the trigger" referred to the mechanism of the gun, not the shooter's action.
"I'm not aware of that in the legislative history," Kavanaugh said. He told Mitchell it would "help your argument if people were drawing that distinction."
The plaintiffs challenging the ban said the legal definition of machine gun has been distorted beyond recognition and argued that courts should not defer to the federal agency's interpretation.
Lower courts are divided on the issue, with both the New Orleans-based 5th U.S. Circuit Court of Appeals and the Cincinnati-based 6th U.S. Circuit Court of Appeals ruling that the ban was unlawful.
The Biden administration appealed in both those cases, while gun rights advocates are contesting a ruling by the U.S. Court of Appeals for the District of Columbia Circuit that upheld the ban.
Notwithstanding the ban currently being in effect, Bumpstock.com, operated by bump stock inventor Jeremiah Cottle, says it will currently ship to the seven states covered by the 5th Circuit and 6th Circuit decisions: Kentucky, Michigan, Ohio, Tennessee, Texas, Louisiana and Mississippi.
Asked if he would plan to sell the product in other states if the rule is struck down, Cottle said in an interview that it would depend on how the justices rule.
"I want to see what the Supreme Court does. I'm not putting the cart before the horse," he added. Cottle, who said he has sold about 100 bump stocks following the recent court rulings, plans to attend the oral arguments Wednesday.
ATF spokeswoman Kristina Mastropasqua said that despite the court rulings, bump stocks for now remain "classified as machine guns" nationwide. As a result, they remain banned.
Even if the regulation is overturned, bump stocks would still not be available nationwide, with 18 states already banning them, according to Everytown. Congress could also take action.
The court has backed gun rights in cases directly addressing the scope of the Second Amendment, including the 2022 ruling that found there is a right to carry a handgun outside the home.
But in a case argued in November, the court indicated it might stop short of striking down some long-standing gun laws in a case involving a ban on people accused of domestic violence possessing firearms.