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Tuesday, June 25, 2024 | Back issues
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Supreme Court shoots down bump stock ban

The high court’s ruling prevents the government from banning a device used in the deadliest mass shooting in U.S. history.

WASHINGTON (CN) — The Supreme Court on Friday ruled that bump stocks cannot be banned, finding that the devices cannot be included in a law banning machine guns. 

Split along ideological lines, the court held that semiautomatic rifles equipped with bump stocks are not machine guns because they cannot fire more than one shot by a single function of the trigger. 

“A bump stock does not convert a semiautomatic rifle into a machine gun any more than a shooter with a lightning-fast trigger finger does," Justice Clarence Thomas wrote for the conservative majority

Bump stocks are an add-on device for semiautomatic weapons that let shooters fire hundreds of rounds per minute. They attach to the end of a rifle held against the shoulder and slide back and forth to trigger the firing sequence. A government estimate put a semiautomatic weapon’s firing capability at around 60 bullets per minute. The bump stock takes that number up to between 400 and 800 bullets per minute.

The George H.W. Bush appointee said releasing and resetting the trigger made firing each shot a separate and distinct function of the trigger — differing from the automatic fire of machine guns. 

“All that a bump stock does is accelerate the rate of fire by causing these distinct ‘function[s]’ of the trigger to occur in rapid succession,” Thomas wrote.

In a fiery dissent, Justice Sonia Sotomayor said the court substituted its own view of what constitutes a machine gun instead of looking to lawmakers’ definition. 

“Today’s decision to reject that ordinary understanding will have deadly consequences,” the Barack Obama appointee wrote. “The majority’s artificially narrow definition hamstrings the government’s efforts to keep machine guns from gunmen like the Las Vegas shooter.” 

President Joe Biden said the ruling struck down an important gun safety regulation. Biden said his administration has used every tool in its arsenal to combat gun violence and called on Congress to pass a bump stock ban.

“Americans should not have to live in fear of this mass devastation,” Biden said in a statement.

The government moved to classify bump stocks as machine guns following the deadly Route 91 Harvest festival shooting in 2017. A gunman used a bump stock to fire over a thousand bullets — approximately nine rounds per second — at the outdoor concert in Las Vegas, killing 58 people and wounding 500 more.

The U.S. has restricted machine guns since the 1930s. In 1986, the government barred new machine guns from entering the market, prohibiting any weapon that is designed to automatically fire more than one shot without reloading.

The Bureau of Alcohol, Tobacco, Firearms and Explosives put spring-loaded bump stocks in this category. Gun manufacturers responded by developing the bump stock at issue in this case, which relies on the shooter’s forward pressure to trigger the device instead of a spring.

Michael Cargill told the court that bump stocks only trigger one shot per function of the trigger, disqualifying them from the language in the 1986 law.

Jonathan Mitchell, an attorney with Mitchell Law representing Cargill, told the justices that the multiple discharges created from the bump stock depended entirely on human effort and exertion. Mitchell said the shooter maintains continuous forward pressure on the barrel of the rifle with the nonshooting hand while also maintaining backward pressure on the weapon with the shooting hand.

The government contested that assessment during oral arguments in February. Brian Fletcher, principal deputy solicitor general at the Department of Justice, said the bump stock was using the gun’s recoil energy to create the continuous back-and-forth cycle that fires hundreds of shots per minute.


Resembling an instruction manual, the court’s opinion breaks down exactly how bump stocks operate on semiautomatic rifles to determine that they do not enable automatic fire. 

The court found that pulling the trigger — the movement required to shoot the firearm — sets off a firing cycle. Each time the trigger is pulled, a semiautomatic rifle must reset, the court said, before beginning another cycle. 

Thomas said adding a bump stock does not change that process. 

“A bump stock merely reduces the amount of time that elapses between separate ‘functions’ of the trigger,” Thomas wrote. “The bump stock makes it easier for the shooter to move the firearm back toward his shoulder and thereby release pressure from the trigger and reset it.”  

The court rejected the government’s theory that pulling the trigger once sets off a bump-firing sequence of multiple shots. The government reasoned that a shooter only had to maintain forward pressure on the rifle after that initial pull, marking only one function of the trigger for multiple shots. 

Sotomayor — joined by justices Elena Kagan, a Barack Obama appointee, and Ketanji Brown Jackson, a Biden appointee — criticized her colleagues for not following the common understanding of machine guns. She said bump-stock-equipped semiautomatic rifles fire more than one shot automatically without manual reloading. 

“When I see a bird that walks like a duck, swims like a duck, and quacks like a duck, I call that bird a duck,” Sotomayor wrote. 

Thomas said this theory fails because there is a difference between a shooter flexing his finger to pull the trigger and pushing the firearm forward against the bump stock. That forward pressure, Thomas said, bumps the shooter's stationary finger against the trigger after each shot. 

Congress’ ban on machine guns, Thomas said, does not hinge on human input or whether the shooter had assistance to engage the trigger. 

“The statutory definition instead hinges on how many shots discharge when the shooter engages the trigger,” Thomas wrote. “And, as we have explained, a semiautomatic rifle will fire only one shot each time the shooter engages the trigger — with or without a bump stock.” 

Sotomayor said the majority focused too heavily on the trigger mechanics when they should have been looking at how a shooter uses a trigger to initiate fire. 

“Regardless of what is happening in the internal mechanics of a firearm, if a shooter must activate the trigger only a single time to initiate a firing sequence that will shoot ‘automatically more than one shot,’ that firearm is a ‘machine gun,’” Sotomayor wrote. 

Thomas said regardless of whether rifles fire more than one shot from one trigger-pull with a bump stock, that sequence does not happen automatically. 

Justice Samuel Alito said the government’s interest in banning bump stocks after the “horrible shooting spree in Las Vegas” did not change the law. 

“That event demonstrated that a semiautomatic rifle with a bump stock can have the same lethal effect as a machine gun, and it thus strengthened the case for amending §5845(b),” the George W. Bush appointee wrote. “But an event that highlights the need to amend a law does not itself change the law’s meaning.” 

Gun rights groups praised the ruling, seeing it as a signal that the court could reverse bans on assault weapons. 

“We are also hoping Justice Thomas and the Supreme Court will soon deliver a similar blow to unconstitutional assault weapons bans beginning with NAGR v. Naperville, especially in light of Justice Sotomayor’s concession in her Cargill dissent that semiautomatic rifles are in common use,” the National Association for Gun Rights said in a statement after the ruling. 

Follow @KelseyReichmann
Categories / Appeals, Second Amendment

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