Three major gun-rights organizations filed a federal lawsuit against Maryland’s new ban on Glock-pattern pistols within hours of Gov. Wes Moore signing the legislation into law.
The lawsuit — NRA v. Moore — was filed May 26 in the U.S. District Court for the District of Maryland by the National Rifle Association, the Second Amendment Foundation, and the Firearms Policy Coalition. Defendants include Gov. Moore, Maryland Attorney General Anthony Brown, and acting Maryland State Police Superintendent Michael Jackson.
The same-day filing reflects how prepared gun-rights organizations have become to challenge state-level firearms legislation as soon as it becomes law — and how clearly the Maryland bill telegraphed its constitutional vulnerabilities during the legislative process.
What Maryland’s law actually does
The legislation, SB 334, makes it unlawful in Maryland to manufacture, sell, offer for sale, purchase, receive, or transfer a “machine gun convertible pistol” beginning January 1, 2027. The law defines that category as:
“Any semiautomatic pistol with a cruciform trigger bar that can be readily converted by hand or by using common household tools into a machine gun by the installation or attachment of a pistol converter as a replacement for the slide’s backplate.”
The technical definition matters because of what it actually covers. The “cruciform trigger bar” is a standard internal component in many of the most popular handguns sold in America, including the entire Glock lineup, the Sig Sauer P320 (the U.S. military’s current standard sidearm), and several Smith & Wesson M&P variants. The cruciform shape is a design feature of these pistols, not an aftermarket modification.
Under Maryland’s new law, the legal status of these handguns turns not on what has been done to them, but on whether they could theoretically be modified using “common household tools.”
The pattern across states
The Maryland law closely tracks the convertible pistol provisions New York included in its state budget bill earlier in May. Both states use the cruciform trigger bar framework. Both target the same class of widely-owned handguns. Both make possession of standard, legally-purchased pistols a crime based on theoretical convertibility rather than actual modification.
The synchronization isn’t coincidental. State-level gun control legislation increasingly moves across multiple jurisdictions on similar timelines and with similar legal architecture, suggesting coordinated drafting and advocacy. New York and Maryland have now created what amounts to a template that other restrictive states are likely to consider.
The federal context for “Glock switches”
So-called “Glock switches” or “auto sears” — small aftermarket devices that convert semi-automatic Glock-pattern pistols to fully automatic fire — are already illegal under federal law as unregistered machine guns under the National Firearms Act. Possession is a federal felony punishable by up to 10 years in prison. Manufacturing, selling, or installing one carries the same penalties.
The federal framework already heavily criminalizes the actual conversion devices. Maryland and New York have chosen to also criminalize the host pistols on the theory that they could be converted, regardless of whether they have been or ever will be.
Gun-rights advocates have warned for years that the “Glock switch” issue would eventually be used to justify banning the underlying pistols. Maryland’s law makes that warning concrete.
The constitutional argument
NRA’s Institute for Legislative Action framed the central legal argument plainly in a legal update on the lawsuit:
“In District of Columbia v. Heller, the U.S. Supreme Court held that ‘common’ firearms cannot be banned and specifically struck down a handgun ban as unconstitutional. Maryland’s prohibition on many of the most popular handguns in America blatantly defies the Court’s precedent.”
SAF Executive Director Adam Kraut characterized the law’s logic as fundamentally backwards.
“Maryland has now attempted to ban these firearms because a subset of criminals illegally modifies them, using conversion parts that are themselves illegal to possess, and then commit crimes with the modified handguns,” Kraut said in an SAF news release. “Not only is this law as foolish as banning hops and barley to prevent drunk driving, but these commonly owned arms are clearly protected by the Second Amendment, the ratification of which takes certain policy choices — including this one — off the table.”
FPC President Brandon Combs used sharper language.
“Maryland’s politicians just declared war on an entire class of constitutionally protected handguns and the peaceable people who want to own them,” Combs said in an FPC news release. “This ban is immoral, unconstitutional, and tyrannical. FPC and our Grassroots Army are going to force Maryland to respect the Second Amendment, full stop.”
The 4th Circuit problem (again)
The Maryland Glock ban lawsuit faces the same procedural reality as the SAF coalition’s Virginia assault weapons lawsuit: it will be litigated in the U.S. Fourth Circuit Court of Appeals, which has been the most hostile federal circuit to gun-rights challenges in the post-Bruen era.
The Fourth Circuit upheld Maryland’s existing assault weapons ban in Bianchi v. Brown (August 2024). The Supreme Court denied certiorari in the renamed Snope v. Brown case in June 2025, leaving the Fourth Circuit’s reasoning intact as binding precedent. The same court that upheld Maryland banning one category of firearms will now be asked to strike down Maryland banning another.
Gun-rights advocates have a stronger handgun-specific argument here than in the assault weapons context. Heller explicitly addressed handgun bans and explicitly struck one down. The Maryland Glock ban is much more directly analogous to the D.C. handgun ban Heller invalidated than the Maryland assault weapons ban was to anything the Supreme Court has previously addressed.
That distinction may or may not matter in the Fourth Circuit. It almost certainly will matter if the case reaches the Supreme Court.
What’s next
For Maryland gun owners, the law’s January 1, 2027 effective date means current Glock and similar pistol owners are not yet criminalized. The question is whether they will be on January 1 — which depends on whether the lawsuit produces injunctive relief in time.
The Maryland lawsuit joins a growing list of post-Bruen legal challenges that the federal court system is working through. Combined with the NSSF’s parallel lawsuit against Virginia’s gun control package, the 2nd Circuit’s vampire rule ruling, and the pending SAF cert petition on Maryland’s sensitive places framework, the courts will be deciding multiple consequential Second Amendment questions over the next 12-18 months.
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