SALT LAKE CITY — A Democratic state lawmaker proposed legislation Wednesday to outlaw a gun accessory in Utah that modifies rifles to fire like automatic weapons.

Meantime, a Utah gun rights advocate will be in federal court Thursday asking a judge to block a newly imposed Trump administration rule banning the device known as a bump stock.

HB331, sponsored by Rep. Patrice Arent, D-Millcreek, would prohibit the import, sale, manufacture and possession of devices that modify a semiautomatic weapon to significantly increase the rate at which it fires. The bill would also allow police to confiscate bump stocks and destroy them.

Bump stocks came under intense scrutiny after a gunman used them to fatally shoot 58 people and wound about 500 more at a country music concert in Las Vegas in 2017.

Arent said she like the rest of the nation was shocked at the Las Vegas massacre. Americans, she said, are ready to talk about "common sense" gun laws. She said she doesn't know if her bill will get any attraction but she hopes it at least gets a committee hearing.

"There is no legitimate use for bump stocks," she said.

Several bills in Congress to outlaw them didn't go anywhere. But the Trump administration in late December adopted a federal rule that redefined the devices as "machine guns," therefore banning them under existing law. The rule takes effect March 26.

"I am getting a little harassment on the hill for agreeing with the Trump administration," Arent said, adding the ban is one where she does agree with the president.

Clark Aposhian, chairman of the Utah Shooting Sports Council, sued the Department of Justice and Bureau of Alcohol, Tobacco, Firearms and Explosives last month, arguing the agencies violated the Constitution in establishing the rule. Aposhian owns a Slide Fire bump stock.

New Civil Liberties Alliance, an organization based in Washington, D.C., that recruited Aposhian for the lawsuit, contends only Congress — not the executive branch — has the power to make laws.

In court papers filed last week, government attorneys argue the Department of Justice acted on presidential instruction to adopt the rule banning bump stocks and corrected a "confusing and erroneous" previous agency interpretation of the law in the interest of public safety.

"This public safety benefit would be jeopardized by an injunction which would allow a terrorist or criminal to use a lawfully possessed bump stock to carry out a large-scale attack," according to court filing.

Aposhian's lawyer, Caleb Kruckenberg, contends that the administrative rule redefines federal law.

"The final rule conflicts with Congress’ statutory language and attempts to rewrite a criminal law that does not apply to Mr. Aposhian in a way that threatens to make him into a felon," he wrote.

Aposhian contends the Trump administration is illegally changing the rules in the middle of the game, and "paying lip service" to the Second Amendment.

The rule requires bump stock owners to destroy the devices or turn them in to the ATF.

Americans own an estimated 520,000 bump stocks, according to the ATF. Sales of the gun accessory soared after the Las Vegas shooting as talk of a government ban picked up.

Some states and cities moved quickly to ban bump stocks after the mass shooting, but have had little success in getting people to give them up.

In Massachusetts, the first state to impose a ban, only a handful of the devices were turned in to state police, USA Today reported in December. Police in Denver reported no surrenders since a citywide ban carrying a fine and jail time was imposed in January 2018.