CEO Shooting Suspect Had a Ghost Gun. What to Know

Police have said the suspect in the murder of health insurance exec Brian Thompson had what's known as a ghost gun in his backpack when arrested. The weapon appears to be the same type of gun used in Thompson's murder, reports NBC News, but ballistics tests are still pending. Luigi Mangione "was in possession of a ghost gun that had the capability of firing a 9mm round," says the NYPD's Joseph Kenny. So what is a ghost gun? Coverage:

• The guns: The term broadly refers to homemade guns put together with kits typically purchased online, per the Guardian. Such kits have been around since the 1990s, but they have exploded in popularity in recent years. Law enforcement seized nearly 26,000 ghost guns in 2022, up from about 1,600 in 2017.

• Legality: Until a few years ago, ghost guns did not need serial numbers, and buyers did not have to undergo background checks, reports the Washington Post. That changed in 2022, when the ATF broadened its definition of the term "firearm" to include ghost guns, per the New York Times. The new rule did not ban the sale of kits, but it required manufacturers to add serial numbers and do background checks. The Supreme Court heard arguments earlier this year challenging that, though the justices seem inclined to keep the tougher rules in place.
• States: In addition to the federal rules, which remain in effect while the Supreme Court weighs the issue, about a dozen states have adopted laws regulating ghost guns, according to the gun safety group Everytown USA. Typically, such rules mandate serial numbers and background checks.
• 3D printers: The NYPD's Kenny says Mangione appears to have used a 3D printer to assemble his gun, a technology that has made the weapons more popular. Scores of how-to videos also exist on YouTube. Going from kit to functioning weapon typically takes about an hour, at a cost of $800 to $1,000, per the Post.

(More Luigi Mangione stories.)