A ban on so-called “ghost guns,” difficult-to-trace weapons that lack serial numbers or are sold in pieces to evade Maryland’s background check rules, will go into effect after Gov. Larry Hogan announced Friday that he would not veto the measure.

Regulating so-called “ghost guns” has been a top priority of gun control advocates for several years but was opposed by many gun-rights groups. Some top law enforcement officials have also pressed for tighter rules, with Baltimore Police Commissioner Michael Harrison and others telling lawmakers that such weapons are showing up with greater frequency at crime scenes.

Supporters of the legislation primarily complained about the growing purchase of firearms assembled at home from kits purchased off the internet. Because the weapons are bought in pieces, buyers can effectively evade current background check requirements — and the weapons can also be particularly difficult for law enforcement to trace, both because there is no paper trail of background checks and sales documents and because the parts typically lack serial numbers.

Champions argued the new ban closes a major loophole in Maryland’s firearms regulations and gives the state a key tool to stem the supply of weapons used in crimes.

Some Republican lawmakers and gun rights groups, however, argued that the new restrictions could ensnare well-intentioned gun owners while a few critics on the left raised concerns that the police could selectively enforce the new law — like other existing firearms restrictions — disproportionately on lower-income communities of color.

The “ghost gun” legislation would change the legal definition of a firearm to include unassembled frames or receivers, two keys parts needed to assemble a working gun. The change would require anyone buying those parts to submit to the same background check and other requirements as anyone buying a fully assembled working weapon.


Buying, selling or transferring an unfinished frame or receiver without a serial number would become a misdemeanor punishable by up to five years in prison and a $10,000 fine.

The legislation would also crack down on other firearms that lack serial numbers. Knowingly possessing a firearm without a serial number would become a misdemeanor punishable by up to two years in prison and a $10,000 fine. The bill exempts antiques firearms and any weapons manufactured before October 22, 1968 from the requirements.

Anyone who owns a weapon outlawed by the legislation will be able to register the gun with the Maryland State Police and have it imprinted with a traceable serial number — as long as they meet the existing criteria for owning a firearm.

The new law will go into effect on March 1, 2023.