What is a ghost gun? Police link untraceable firearm to suspect Luigi Mangione in CEO death
Long before the death of CEO Brian Thompson, the home-made weapons were spreading across the US
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When the New York City Police Department caught up with the man accused of killing UnitedHealth CEO Brian Thompson, they found him with multiple fraudulent IDs and a 9mm “ghost gun,” according to authorities.
What is a ghost gun? Since the rise of 3D printers in the early 2010s, these untraceable firearms have become more and more common in American criminal cases.
Yet because these weapons have no serial numbers, it's basically impossible to know how many have been sold, how many are in circulation, and the number used in crimes.
What gun was found on Luigi Mangione?
We don’t know much about the weapon that police believe may have been used to gun down Brian Thompson outside his Manhattan hotel last Wednesday.
When police detained 26-year-old Luigi Mangione he was “in possession of a ghost gun that had the capability of firing a 9mm round, and a suppressor,” NYPD Chief of Detective Joseph Kenny at a press conference Monday.
Kenny added that the weapon “may have been made on a 3D printer.”
If true that would be one of many. Last year, the US Department of Justice announced that requests from local police forces to trace ghost guns used in crimes had risen by more than 1,000 percent since 2017, from 1,629 reports to an astounding 19,273.
How are ghost guns created?
A ghost gun is a homemade firearm that bears no serial number, meaning it cannot be traced back to its original buyer if it is used in a crime.
It has always been possible to build such guns, but 3D printing has made it easier than ever before, and blueprints to do so are widely circulated on the internet.
Until recently, a quirk in US firearms laws made it unclear whether these sorts of guns could even be regulated.
Under the Gun Control Act of 1968, anyone who wants to manufacture guns for sale or distribution must put a serial number on every weapon they produce. The 1993 Brady Act added a requirement for background checks on prospective gun buyers.
But traditionally, the requirements pertained to the existence of a "frame or receiver" – ie, the overall chassis of the gun into which all other components are integrated – that made a gun a gun.
This led to numerous companies selling built-it-yourself firearm kits containing all the components that make up a gun, except for the “frame.” These were legally considered mere gun parts, rather than actual guns, and therefore not subject to the same controls.
Users could then utilize tools or a 3D printer to complete the kit by building their own receiver or frame, creating a usable and untraceable gun.
Over the past decade, ghost guns have been used in a number of high-profile crimes.
What havoc have they wrought so far?
The gun regulation group Everytown For Gun Safety lists 198 separate shootings using ghost guns between June 2013 and September 2024,
In 2013, a 23-year-old man wielding a home-assembled AR-15 style rifle – who had previously failed a background check – killed five people and injured two others in a shooting spree in Santa Monica, California.
In 2017, another gun rampage in rural northern California killed four people and injured at least eight others, seven of whom were children. The murderer had circumvented a court order banning him from gun ownership by building his own AR-15 style rifles at home, according to police.
In 2023 a man carrying two ghost guns killed five people and wounded two in Philadelphia, leading the city government to file a lawsuit against Polymer80 and JSD Supply, two gun component vendors.
The lawsuit claimed that roughly 87 percent of ghost guns seized by Philly police as part of criminal investigations that year had included parts made by Polymer80.
The two companies ultimately settled the suit, earlier this year in April, agreeing to pay $1.3 million on gun violence prevention efforts and to not sell their products to anyone within the city for the next four years.
What are authorities doing about it?
Law enforcement authorities have filed similar suits, including actions by two Los Angeles county sheriffs allegedly wounded in a ghost gun ambush in 2020, against Polymer80 and other companies,
Many states have also passed laws regulating home manufacture of firearms, including California, Colorado, Illinois, Nevada, New York and Pennsylvania.
In 2022, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) adopted a new rule that defined built-it-yourself kits as firearms in and of themselves, meaning they were subject to the same regulations.
It also required federally licensed gun dealers who receive a firearm with no serial number to add their own number that could be traced back before selling it to anyone else.
According to the Associated Press, these regulations have reduced the problem. Police seizures of ghost guns have reportedly declined in major cities such as Philadelphia, New York, Los Angeles and Baltimore.
But firearm kit makers, backed up by gun rights groups and attorneys general in Republican-controlled states, have challenged this law, arguing that the ATF overstepped its legal bounds.
A challenge to the law is still before the Supreme Court. It’s unclear whether the court’s conservative supermajority will uphold or strike down the new restriction.