May 20, 2024
Matt Stone/USA TODAY NETWORK
Next to the Glock pistol shown above is a small, machine gun conversion device called a switch that turns semi-automatic handguns into fully automatic weapons.
When three teenagers opened fire at a SEPTA bus stop in Northeast Philly in March, injuring eight students on a rainy Wednesday afternoon, at least one of them was armed with a pistol that had been converted into a fully automatic machine gun using a small device called a switch.
Within seconds, more than 30 shots had been fired near the corner of Cottman and Rising Sun avenues in a harrowing flash of gunfire captured on surveillance video. During the investigation, which has since led to five arrests, police recovered a 40-caliber Glock 22 handgun with an extended magazine. Bullet casings at the scene were matched to the gun, which resembles many others that have been used in shootings in Philadelphia, authorities said.
"We see a lot of crime scenes where it looks like one or more guns have been completely emptied, even if we don't have video of the incident," Philadelphia District Attorney Larry Krasner said. "Even if we don't have guns or any suspects, simply seeing 50 different cartridge casings coming from three different guns is a hint that all of them or at least some of them have a switch. I think it's even more prevalent than we see because we frequently don't see the gun later."
The spread of fully automatic pistols has become a growing national concern. The federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) recorded a 570% increase in the number of such devices recovered by police departments between 2017 and 2021, the most recent period with available data on their prevalence, the agency said.
As more of these modified guns wind up in the hands of criminals, law enforcement officials in Pennsylvania and other states are calling for laws that will strengthen prosecution beyond the existing federal ban on switches. Those efforts are gaining momentum at the city and state level, where proposals are being considered by lawmakers.
"This is another example of the need for our laws to stay up with technology," Montgomery County District Attorney Kevin Steele said. "This is another device that's being introduced to deadly consequences."
Machine gun conversion devices — also called auto sears, giggle switches or buttons — are small, cheaply made tools designed to alter the mechanics of the trigger bar on a semi-automatic pistol. When attached to the rear slide of a handgun, they prevent the trigger from catching on the firing pin. Instead of having to pull the trigger for each round fired, simply holding it with one pull will continuously fire rounds.
"If you hold down the trigger, you will expel as many rounds as there are loaded," said Neil Zubaty, a special agent with the ATF's Philadelphia office.
Although the devices are often called "Glock switches," they can be produced in different sizes and shapes to fit handguns from a wide range of manufacturers.
"They're interchangeable to a degree. Some are manufactured with metal or steel parts. Some are 3D printed. They can be as creative as the designer (wants) depending on the type of firearm," said Eric DeGree, special agent in charge of ATF's Philadelphia field division, who has worked on investigations of crimes involving gun switches.
With few exceptions, switches are federally banned for civilian use by the National Firearms Act and the Gun Control Act. Possession of a switch, even in the absence of a gun or a crime committed with one, can be punishable with a sentence of up to 10 years in federal prison.
But one of the biggest enforcement challenges is detection, since it isn't visually obvious when an otherwise legal, semi-automatic pistol is equipped with a switch. Only when the weapon is fired, or if the gun is recovered by police and then disassembled, will investigators discover if a switch is used.
"We've seen them in a myriad of investigations ATF handles in Philadelphia," DeGree said. "We have several criminal enforcement groups that deal with carjacking and firearms trafficking, or other violent crimes such as commercial robberies. They're showing up in pretty much every investigation that we're conducting."
Philadelphia police declined to comment on investigations involving gun switches and did not respond to requests for data on how many of them have been recovered. The DA's office also could not provide data on their use in city crimes.
Over the years, the ATF's investigations have determined that high volumes of switches are manufactured in China and shipped overseas to the United States. Increasingly, they're also being manufactured domestically using 3D printers. A switch can often be bought for $50-$100 and then attached to a handgun with relative ease.
"It's our belief that a majority of these guns are coming from either vehicle thefts or residential thefts," Zubaty said. "A lot of them are stolen. People under 21 can't purchase handguns at a gun store. They're also getting into teens' hands through straw purchasers, or juveniles are buying them on the street."
A pistol that has a switch installed has the technical firepower to shoot up to 1,200 rounds per minute. Practically speaking, a large number of magazines would be needed to unload that much ammunition. But the firing capacity of a switch turns a handgun into a much more unpredictable weapon.
"It's an inherently dangerous item," Zubaty said. "Controlling and managing that recoil is considerable. And if you have an extended magazine on there, it's simple math. You're able to put more rounds down range."
Part of the motivation for equipping guns with switches is to project a message.
"There's a perceived notion that, 'I now have a more dangerous type of firearm,' which it is," Zubaty said. "I also believe it's an intimidation factor. Sometimes suspects make it known that they may be carrying a fully automatic firearm."
Extended magazines come in varying sizes — often 15 to 30 rounds — that can double the ammunition available to fire before reloading. There are even circular, 100-round drum magazines that can be fitted in a Glock and are reminiscent of the 1920s Thompson machine guns often seen in old movies.
"People have been manipulating semi-automatic firearms and full auto firearms for quite some time," DeGross said. "I believe that now the process of manufacturing them has become more readily available to the person on the street. That's why there has been more prevalence of these things showing up in crimes."
Montgomery County prosecutors used a video demonstration of a gun with a switch during a sentencing hearing for a defendant convicted of committing a string of armed robberies in Norristown in 2018. Montgomery County Detective Eric Nelson, a firearms and ballistics expert, showed the judge how one of the guns recovered in the investigation worked with a switch.
"One of the ramifications of this device is that it causes the person to have less control over where they're shooting," Steele said. "What we've seen when we've experimented with these is that even with an expert ballistics detective, this is hard to control. It turns an automatic, where you would aim each time and pull the trigger, into a machine gun, and that causes the gun to spray. There may be unintended targets because of that."
Steele said the spread of handguns with switches is a growing threat to police officers.
"They see a gun being raised — you can't tell whether a conversion device is on it until that trigger gets pulled," Steele said. "And then it's a barrage of bullets that are coming at you like a machine gun. We're looking for a ban on these devices ... because we and our police officers on the streets are being outgunned with people having them."
The Montgomery County DA's office conducts trainings with police departments to help officers identify weapons that have switches and find them in evidence rooms where they may have gone unnoticed.
Krasner called switches "an enormous problem at every level," explaining that they specifically cater to criminals.
"They are usually in the hands of people who are up to no good. We do not see a whole lot of people who seem to be Joe Citizen with a bootleg switch in a gun," he said. "This should be one of those items that we all recognize as being inconsistent for lawful self-protection and more consistent for a warlike mentality that goes with criminal activity."
A number of states have passed laws to ban switches and enable prosecution that doesn't rely on federal law.
Even in Republican-led states like Virginia and Mississippi, where gun rights are often vigorously defended, new restrictions have been placed on switches. This month, Maryland passed a law banning them and New York proposed a sweeping measure that would outlaw any firearm that could be modified with a switch. Chicago filed a lawsuit against Glock seeking to compel the company to make it more difficult for their guns to be modified with switches.
In Pennsylvania, the legislative push to ban switches has been divided along partisan lines. Two gun control bills — including one that would ban switches — were narrowly defeated in the House of Representatives by a 101-100 vote. State House Minority Leader Bryan Cutler (R) said he opposed the measure on switches because it's already covered by the National Firearms Act.
“I understand the issues of gun violence,” Cutler said after the vote. “I understand the desire to blame inanimate objects such as a firearm and that’s exactly what this bill does."
Steele serves as the legislative chair of the bipartisan Pennsylvania District Attorney Association. He said he and his colleagues do not intend to give up on getting the law passed.
"We took a vote on our priorities for legislation. This is number one — a ban on these devices," Steele said. "I hope the legislature will listen to prosecutors and law enforcement across the state."
Last week, Philadelphia City Councilmember Isaiah Thomas (D) introduced a bill to ban switches in the city, citing the shooting at the bus stop in Northeast Philly. The proposal has the support of Mayor Cherelle Parker (D) and will be reviewed in the coming months.
"These devices facilitate mass shootings and have no place on the streets of Philadelphia," Parker said.
Both Steele and Krasner argue the federal ban on switches has become inadequate in light of how widespread the devices are on the street. The majority of criminal cases in the United States — more than 90% — are handled by state and local prosecutors. Opportunities to effectively prosecute cases involving switches are limited both by law and resources.
"There is a bandwidth issue," Krasner said.
In some instances, local cases are turned down by federal prosecutors because they don't meet the threshold to be pursued. Federal agencies such as the ATF assist local police and prosecutors in criminal cases, but defendants who have guns with switches may never be charged for that particular offense in the absence of local laws.
"We're the ones that are prosecuting these cases and we need laws to ban machine gun conversion devices," Steele said. "It is not taking away anyone's guns. Pure and simple. This is simply not allowing a device that turns a semi-automatic into a machine gun."
Krasner said the issue dovetails with the need to crack down on ghost guns, the firearm assembly kits that can be purchased from multiple sources to customize weapons and bypass regulation. The state House passed a bill in March banning ghost guns and sent the proposal to the Senate for review.
"We've gotten to the point where people can become their own gun manufacturers courtesy of the parts that are available for ghost guns and 3D imaging," Krasner said.
The Philly DA likened the evolution of gun laws to the federal ban that heavily restricted silencers — also known as suppressors — in the 1930s.
"There was a recognition there that not every add-on for a weapon is OK," Krasner said. "Given the obvious intent of a silencer — which is not actually to make a gun silent, but to make it so that it is quieter and you cannot tell from which direction it is coming ... there has been an understanding that there are some things that are beyond the pale."
Krasner said he supports laws that will ban switches but suggested the conversation about preventing gun violence ultimately needs to be broader to see measurable results in crime reduction.
"We can mess around with these details, but until we get to a point of having some sense overall about reasonable gun regulation, we're never going to have the really, really low levels of gun homicide and shootings that we see in countries where they have had no problem doing that," Krasner said.
