President Joe Biden has announced a series of executive actions directed at dealing with what he calls a “gun violence public health epidemic” after a number of recent mass shootings throughout the country.

Among Biden’s actions was one targeted at “ghost guns,” and he’s asked the Department of Justice to come up with a proposal within 30 days to help “rein in” the problem.

Ghost guns have become popular in recent years, but because they are untraceable, there is no good data indicating how many have been sold or are in circulation, says Alex McCourt, director of legal research at the Johns Hopkins Center for Gun Violence Prevention and Policy. According to a 2020 report from Everytown for Gun Safety, an anti-gun violence nonprofit, many ghost gun sellers found “their inventories stretched thin” because of increased demand in 2020.

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Some law enforcement agencies are recovering more ghost guns from crime scenes. In Philadelphia, for example, 99 ghost guns were recovered in 2019, jumping to 250 in 2020. And, as of mid-March this year, more than 80 had been recovered, according to Pennsylvania Attorney General Josh Shapiro.

So, what exactly is a ghost gun, and are they illegal in Pennsylvania or Philadelphia? And how could President Biden’s executive action regulate them? Here is what you need to know:

What is a ghost gun?

Ghost guns are DIY firearms made at home, usually from parts or kits bought online, though some parts can be 3-D printed. Ghost guns are not required to have serial numbers, and you do not have to undergo a background check to purchase the parts to make one. Typically, they are relatively quick and easy to build into a functioning firearm, compared to making a gun from scratch, which requires special tools and knowledge.

“The analogy you often see people use is IKEA furniture,” says David Pucino, staff attorney with the Giffords Law Center to Prevent Gun Violence. “It’s designed for the everyday user to be able to do it with simple household tools.”

The guns are often made with what is known as an 80% frame or receiver, which acts as a base that holds all the parts that make a functioning gun. The frame requires some work first, which can be done with tools like a Dremel and drill, and specialized finishing jigs that simplify the process.

Under current federal law, unfinished frames and receivers are not considered firearms, so background checks and serial numbers aren’t required to buy and sell them. (Traditionally manufactured guns contain frames or receivers that have serial numbers, and require a background check to purchase.)

But homemade guns are not new. People who aren’t otherwise prohibited from owning firearms have long been able to make their own unserialized guns, provided they are for personal use and not for sale — and some people do so as a hobby. You aren’t allowed to make a gun that can elude a metal detector or x-ray machine, and there are restrictions on certain kinds of guns, but generally, it’s allowed.

But because these parts and kits have made building one easier, there’s been a proliferation of ghost guns, says Adam Garber, executive director of CeaseFirePA. That means more chances for ghost guns to be sold illegally or used in a crime.

“By lowering the bar so that most people can figure out how to create a firearm, it increases the risk that someone will do so and resell them, which is what we’ve seen again and again,” he says. “You have to be extremely skilled to truly build a weapon from scratch and not have it potentially blow up.”

Are ghost guns illegal in Pennsylvania?

Ghost guns are not illegal in Pennsylvania, and Pennsylvanians who can legally own guns can legally build them. (By contrast, ghost guns are illegal in New Jersey.)

But State Attorney General Josh Shapiro, has tried to regulate ghost guns in recent years. In December 2019, he issued a legal opinion that unfinished frames and receivers should be considered firearms under state law by Pennsylvania State Police. State police then directed gun dealers to perform background checks when people bought those parts.

But in January 2020, Commonwealth Court Judge Kevin Brobson issued a preliminary injunction on that policy, writing that the it was “unconstitutionally vague” and “sows confusion within the industry and the public.” The matter is currently being litigated.

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Shapiro has continued to work on the issue, and in March 2021 announced an agreement with Eagle Arms Productions, the state’s largest gun show promoter to ban sales of ghost gun kits at its events. This came after surveillance at the Morgantown Gun Show resulted in the arrest of four Philadelphia men suspected of illegally making and selling ghost guns in the city. Eagle Arms is reportedly the first gun show promoter in the country to take this action.

“The state attorney general has been quite aggressive in trying to go after these using his authority,” McCourt says.

Does Philadelphia have laws against ghost guns?

While Pennsylvania has no state laws that directly address ghost guns, Philadelphia does. In fact, in 2013, Philadelphia became the first city in the country to ban the 3-D printing of firearms.

That 2013 law prohibits people from 3-D printing guns or parts, unless you have a federal license to manufacture firearms. In January 2021, the law was amended to also regulate unfinished frames or receivers and the specialized tools used to turn them into functioning weapons.

Now, it’s illegal to buy, sell, or transfer unfinished frames and receivers, jigs and specialized finishing mills in the city, unless both parties are federally licensed. But the law only extends to Philadelphia.

“I think it is a great piece of legislation that will help make Philadelphia safer,” Pucino says. “The problem is, of course, gun traffickers don’t respect city limits.”

What will Biden’s executive action on ghost guns do?

Right now, that’s not entirely clear. The Justice Department will issue their proposed rule by early May, and then it will be open to public comment before being finalized.

The scope of the proposed rule is currently unknown.

“It sounds like they’re going to at least bring kits under the umbrella of ATF regulation of firearms, meaning that you have to undergo a background check to buy them from a federally licensed dealer, and they will be required to have a serial number,” Garber says.

That would make buying the parts or kits essentially the same as buying a regular gun, says Pucino. And it would help keep ghost guns out of the hands of people who are prohibited from owning firearms.

“That won’t prevent people from making their own guns at home,” Pucino says. “They’ll just be sold after there is a background check, and there will be a serial number so they can be traced.”

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Expert sources:
  • Alex McCourt, director of legal research at the Johns Hopkins Center for Gun Violence Prevention and Policy

  • David Pucino, staff attorney with the Giffords Law Center to Prevent Gun Violence

  • Adam Garber, executive director of CeaseFirePA.