This is something that I thought that I’d ever write but Sen. Dianne Feinstein (D-CA) is correct. To be more precise, she is correct on one thing. That is that any ban on bump stocks is the business of Congress and not a regulatory agency.
In an op-ed published Wednesday in the Washington Post, she wrote:
Automatic weapons produced before 1986 are highly regulated, and the Bureau of Alcohol, Tobacco, Firearms and Explosives tracks them. Despite this, the agency has consistently stated that bump stocks could not be regulated under the current law. That was because they do not fit the legal definition of an automatic weapon under the National Firearms Act.Feinstein goes on to say that banning bump stocks by executive fiat opens it to legal challenge and that the Final Rule provides a roadmap for the "gun lobby" to do just that. This is not to say that Feinstein is pro-bump stock. Far from it. She wants them banned along with "trigger cranks" but says it should be done by Congress. Part of her rationale is that if it is done by Congress a future President can't change his or her mind about bump stocks and ditch the ban. The other part of her rationale is the feeling that President Trump and the BATFE with the ban are intruding upon a Congressional prerogative.
Automatic weapons are defined by their ability to fire a continuous number of rounds by holding down the trigger. Bump stocks and other accessories have made this definition largely obsolete, creating a loophole that circumvents Congress’s intent to bar civilians from achieving automatic rates of fire. That’s because the recoil of the stock “bumps” the finger against the trigger, allowing the weapon to achieve automatic fire. Because of this technicality, bump stocks have not run afoul of the law.
ATF initially concluded that it could not ban these devices through regulation in 2008. And after the 2012 shooting at a movie theater in Aurora, Colo., ATF further explained in a 2013 letter to Congress that it could not take unilateral action because “stocks of this type are not subject to the provisions of federal firearms statutes.” In addition, internal ATF documents made public through Freedom of Information Act requests by Giffords Law Center and Democracy Forward show that the agency had reiterated its lack of authority to ban bump stocks unilaterally and that it had approved similar devices as recently as April 2017 — under the Trump administration.
In March 2018, the Justice Department did an about-face, claiming that bump stocks do, in fact, fall under the legal definition of a machine gun and therefore can be banned through regulations. The administration’s position hinges on a dubious analysis claiming that bumping the trigger is not the same as pulling it.
The bump stock ban is already being challenged in District Court in Guedes et al v. BATFE et al. Gun Owners of America have also been promising a lawsuit which as of this afternoon still hasn't been filed.