Legislators have their eyes set on 3D-printed guns like the one allegedly used in the killing of United Health Care CEO Brian Thompson earlier this month.

The weapons are a type of “ghost gun,” unregulated firearms that complicate criminal investigations.

Rep. Melissa Shusterman, D-Chester, has announced her intention to introduce a bill that would regulate them in the 2025 legislative season. The legislation would require 3D-printed firearms to be treated like any other gun and restrict production to those with a federal gun manufacturing license.

“3D-Printed guns shoot like a gun and they can kill like a gun,” Shusterman said. “It’s common sense we should regulate them like guns.”

The Pennsylvania State Police say seizure of ghost guns doubled between 2022 and 2023. Nationwide, the Bureau of Alcohol, Tobacco, Firearms and Explosives saw a 1,000% increase in ghost gun reporting from local law enforcement from 2018 to 2021.

The use of 3D printers in general has evolved and expanded rapidly over the past decade as costs have decreased and the expertise required to use them has lowered, allowing for them to land in the hands of more consumers.

According to DreamBot 3D, a company that sells printers specifically for gun production, the printers required for this kind of work range from just $2,000-$20,000.

“We’re seeing the criminal use of ghost guns rise at an alarming rate. To aid law enforcement efforts to crack down on untraceable guns, our laws must apply to 3D-printed firearms,” said Shusterman.

Another bill concerning ghost guns, House Bill 777, was put forth by Rep. Morgan Cephas, D-Philadelphia. It expired during the 2023-2024 legislative session after passing the House and stalling in the Senate Judiciary Committee. It aimed to ban the sale of kits used to make ghost guns.

“Law enforcement officials need these tools to be able to protect our communities across the state from deadly firearms ending up in the wrong hands,” Cephas said. “I support Rep. Shusterman’s legislation to treat 3D-printed guns as any other firearm under our current laws and renew support for my correlated legislation that would make these guns illegal to create, sell and possess.”

Beyond their untraceability after the fact, a major concern surrounding ghost guns is their potential to be undetectable before a crime is committed. 3D-printed guns can be made of plastic, allowing them to pass through security checks like metal detectors.

Gun rights advocates note that it is illegal, even for 3D-printed guns, to be made entirely of plastic. By law, they are required to at least include a metal plate that would make them susceptible to detection. It is not a given, however, that anyone printing a gun would choose to abide by that requirement.

Advocates for gun reform say that ghost guns allow criminals to circumvent the common sense laws in place to limit violent crime and prohibit firearms from ending up in the wrong hands.