What to know about the ‘ghost gun’, the weapon allegedly tied to the CEO shooting

The man was arrested on Monday in the fatal shooting of UnitedHealthcare CEO Brian Thompson was allegedly in possession of a type of homemade weapon known as a “ghost gun.”

Luigi Mangione, 26, whom police named a “strong person of interest” had a “ghost gun that could shoot 9mm round and a suppressor” when he was arrested on weapons charges by Altoona, Pa., New York Police. The department’s chief of detectives, Joseph Kenny, told reporters.

A senior law enforcement official told NBC News that the weapon found in Mangione’s possession appears to be similar to the weapon used in the Manhattan murder. Kenny said the weapon “could be made on a 3D printer.”

What are Ghost Weapons?

“Ghost guns” are firearms that can be assembled at home from parts purchased online. These parts can usually be obtained without a background check and do not have serial numbers.

How long have ghost weapons been around?

DIY kits have been around since the 1990s, but have exploded in popularity in recent years – especially among criminals.

Between January 2016 and December 2021, the federal Bureau of Alcohol, Tobacco, Firearms and Explosives said it received about 45,000 reports of suspected privately manufactured firearms found by law enforcement in criminal investigations – including 692 homicides or attempted homicides.

The number of ghost guns recovered rose steadily each of those years, from 1,758 in 2016 to 19,344 in 2021, according to the Justice Department.

Technology has also contributed to the steep rise – online videos on how to assemble the guns have millions of views, while some sellers offer 3-D printing files so that customers can print and assemble the weapons themselves and without serial numbers.

The Ministry of Justice said in a 2022 fact sheet that unserialized firearms are incredibly difficult to trace—the ATF reported that it was only able to trace 0.98% of suspected ghost guns submitted by law enforcement to an individual buyer.

What is the government doing about it?

In 2022, President Joe Biden announced restrictions on ghost gun sales with the finalization of a rule requiring gun kit manufacturers to include serial numbers on firearms and for sellers to follow the same standard as with other guns, including requiring a background check for purchase.

“These guns are the weapons of choice for many criminals,” Biden said, and “we will do everything we can to take that choice away from them.”

Gun rights groups and manufacturers have challenged the ATF rule in court, with a federal judge in Texas and an appeals court ruling against the Biden administration. The Supreme Court has twice ruled that the rules can remain in place while the trial continues.

Gun safety advocates, meanwhile, have called on Congress to intervene on the issue to close loopholes and make the rule a law. Over a dozen states have also passed laws regulating ghost guns, according to Everytown for a gun safetya gun violence prevention organization.

The group and others have also called on Congress to act on 3D-printed weapons, which the Trump administration loosened rules on in 2020. There is no federal law barring them, but the ATF says it is illegal to make them available for sale without a license and that they must be able to detected by metal detectors and X-ray machines. A number of states also have individual laws that regulate or ban the guns, according to Everytown.