WASHINGTON (NEXSTAR) – The U.S. Supreme Court debated Wednesday whether a bump stock device turns a semiautomatic weapon into a machine gun.

The attorney for a Texas gun shop owner said he wants the justices to overturn a ban on the gun accessory.

“It has a very high rate of fire, but it’s not automatic,” argued Jonathan Mitchell. 

President Donald Trump’s administration banned bump stocks in response to the 2017 mass shooting in Las Vegas that killed 60 people and wounded hundreds. It’s the country’s deadliest mass shooting in modern history.

“I can certainly understand why these items should be made illegal,” said Justice Neil Gorsuch.

However, Gorsuch, one of Trump’s appointees, questioned the ban’s fairness. He worries gun owners don’t know they could face criminal charges for still possessing bump stocks.

“Because people will sit down and read the Federal Register… that’s what they do in their evening for fun… crack it open next to the fire and the dog,” Gorsuch said. 

The attorney for the U.S. Justice Department shot down those concerns and defended the ban on bump stocks.

“Those weapons are machine guns,” said Deputy Solicitor General Brian Fletcher.

This case though is not about Second Amendment gun rights, but whether a federal agency overstepped its authority in imposing the ban.

“At some point, you have to apply a little bit of common sense,” said Justice Elena Kagan. 

Kagan hinted the law allowed the Bureau of Alcohol, Tobacco, Firearms and Explosives to do this, but Mitchell argued government agencies don’t have this power.

“That’s ultimately a decision for Congress to make,” he said. 

The justices’ decision in this case is expected by early summer.