What makes a gun a gun? New ‘ghost gun’ regulation explained.

Stepping away from his lectern in the White House Rose Garden, April 11, President Joe Biden walked to a nearby display and picked up two parts of a handgun. 

“It’s not hard to put together,” he said. With a drill, at home, “it doesn’t take very long. Anyone can order it in the mail. Anyone.”

The president was holding two pieces of a “ghost gun,” a firearm manufactured without a serial number. Without a background check and for about $150, Americans can order those parts online as a kit and then put them together like a ballistic Lego set. Mr. Biden’s event at the Rose Garden was an attempt to end that. There, he announced a new rule from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) that will regulate those gun kits like any other gun. Experts say the rule, taking effect this August, will close a huge loophole in existing gun laws. 

What is a ghost gun?

It’s “a gun that is impossible or difficult to trace because it lacks a serial number or other identifying markings,” says Alex McCourt, an assistant professor at the Johns Hopkins University Center for Gun Violence Solutions. 

The ATF requires gun manufacturers to mark their weapons, like auto companies leave vehicle identification numbers on cars. These numbers are often etched onto the lower receiver – the part of the gun that holds the trigger, hammer, and slot for the magazine. 

Ghost guns are manufactured without these numbers. Most commonly, they come in the form of unmarked kits sold online with all the components of a firearm – almost always a handgun – that customers  put together at home. It just takes the included directions, basic tools, and about half an hour.  

Until now, in certain circumstances, that was legal. That’s because those kits weren’t actual firearms, in the eyes of the ATF. For decades, the bureau’s standard for what makes a gun a gun has been whether an object can be “readily” converted into a firearm. Around 2005, the agency published its criteria for that standard, and manufacturers started selling products just below the threshold, says Garen Wintemute, a violence prevention expert at the University of California, Davis.

“These guns are made entirely outside any sort of regulatory framework or oversight,” he says. “That’s the point.”  

Why are they dangerous?

Increasingly, ghost guns are showing up in crime scenes. 

Reliable data are hard to find for weapons designed not to be tracked. But in California, Professor Wintemute says, these weapons are recovered in 30% to 50% of gun-related crime scenes. The Department of Justice (DOJ) says law enforcement collected more than 20,000 “suspected ghost guns” during investigations last year. That’s 10 times more than they collected in 2016.

That increase presents two policy problems, says Professor McCourt. Law enforcement traces weapons recovered at crime scenes back to their owners through a background check database. That system is, in part, how police apprehended the lead suspect in the recent Brooklyn subway shooting in New York City. No serial numbers mean no tracing. 

Because ghost gun kits aren’t regulated like regular guns, they also don’t require background checks. That meant a massive legal loophole for children or people with mental illnesses or criminal records that bar them from gun ownership.

“If these kits are available to them, then the law loses some of its teeth,” says Professor McCourt. 

How are they now regulated?

A new “final rule” announced by the ATF and DOJ now treats gun kits as guns, requiring serial numbers and background checks. It also requires any company, such as a gunsmith or gun shop, that comes across a ghost gun, to serialize it, and for federally licensed gun dealers to keep permanent purchasing records – previously only required for 20 years. The regulations go into effect this August. 

This doesn’t spell a total end to ghost guns, says Professor Wintemute. With milling machines or 3D printers equipped with the right code, criminals and people skeptical of government regulation – the two main markets for ghost guns – can still make their own, unmarked firearms. But those machines are expensive and inaccessible to much of the public, says Professor Wintemute. 

The rule “really throws a monkey wrench into the ghost gun market,” he says. 

Organizations like Gun Owners of America have already said they will challenge the rule in court, arguing that it ends the online sale of gun parts. But the ATF is likely within its authority to make the change, says Rafiq Ahmad, a former bureau special agent. 

“It’s not government overreach,” he says. “It’s proper oversight.”