The Justice Department on Saturday took another step toward banning bump stocks — which effectively turn semiautomatic weapons into automatic ones — submitting to the Office of Management and Budget a proposed regulation that would prohibit the sale of the devices.

The step is incremental, and the Justice Department still must go through a lengthy process to make the proposed regulation a reality. If the Office of Management and Budget okays the proposed regulation, it would then be published, with members of the public allowed to comment, before a final version was put into place.

But the step is tangible evidence that the department is working toward regulating the devices, however gradual that work might be.

“President Trump is absolutely committed to ensuring the safety and security of every American and he has directed us to propose a regulation addressing bump stocks,” Attorney General Jeff Sessions said in a statement. “To that end, the Department of Justice has submitted to the Office of Management and Budget a notice of a proposed regulation to clarify that the National Firearms and Gun Control Act defines ‘machine gun’ to include bump stock type devices.”

Officials at the Justice Department began pushing toward regulation of bump stocks in the days after a gunman using such devices shot and killed 58 people on the Las Vegas Strip in October. They asked the Bureau of Alcohol, Tobacco, Firearms and Explosives to reconsider a years-earlier opinion it could not legally restrict the devices. And in December, Sessions announced that he was initiating the process to potentially change federal regulations and would be accepting public comments through Jan. 25.

He would have to complete a similar public comment process if the Office of Management and Budget approves the proposed regulation.

The matter is more complicated than meets the eye. While bump stocks effectively turn semiautomatic weapons into machine guns — which are already regulated — it is debatable whether they do so in such a way that the stocks are encompassed under existing law.

The law defines a machine gun as a weapon that fires more than one shot with “a single function of the trigger.” Current iterations of the bump stock technically produce multiple trigger pulls, using a gun’s recoil against a shooter’s trigger finger to speed up the fire rate.

The National Rifle Association does not oppose ATF’s acting on bump stocks under existing law — although it has objected to new legislation aimed at the same effect. Those who want to see the devices regulated say legislation would be a far easier and more effective way to ban them, as a change in regulation is surely to be met with legal challenges from manufacturers.

The debate over bump stocks drew new attention last month, after the mass shooting at Marjory Stoneman Douglas High School in Parkland, Fla. Nikolas Cruz, the 19-year-old suspect who is charged with killing 17 people in that incident, did not use a bump stock, according to police, though his case has sparked a nationwide push for a variety of gun-control measures. On Friday, Florida Gov. Rick Scott (R) signed a law for his state imposing a three-day waiting period for most purchases of long guns, raising the minimum age for buying those weapons to 21 and banning the possession of bump stocks.