Nearly 15,000 firearms in Philadelphia recovered in criminal investigations or confiscated from people who possessed them illegally can be traced to nine local firearms dealers, according to an analysis of previously confidential records.

The report, by the gun-control group Brady, supports what other studies have shown — that a small number of gun shops in Pennsylvania supply the majority of the state’s crime guns.

But by cross-referencing publicly available trace data with gun dealers’ phone numbers, Brady was able to identify those selling the most Philadelphia crime guns.

The report provides the most comprehensive look in two decades at the origins of thousands of guns used, or suspected of being used, in a crime, or obtained by a person who was prohibited from having a gun. It also recommends more restrictions and transparency around firearms sales.

Statewide, the report found that while many Pennsylvania dealers were linked to few or no crime guns, a small number of dealers sold the guns originally: Just 1% of the in-state dealers were responsible for half of the recovered crime guns, and 20% of the dealers accounted for 90% of the guns.

“What we need as a society is when a shooting happens, we’re not only asking who pulled the trigger, but where did the gun come from?” said T. Christian Heyne, Brady’s vice president of policy.

The largest number of Philadelphia crime guns (2,842) in the study were traced to Colosimo’s, a once-notorious shop on Spring Garden Street that was shut down in 2009.

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Joshua Scharff, Brady’s legal counsel and director of programs, said that the data set goes back to 1977, but is more comprehensive in recent years, when the state Attorney General’s Office started focusing on gun tracing and data sharing.

”These numbers for closed stores really show you the damage that an irresponsible dealer can do,” Scharff said. “These guns are durable and they have a long life.”

Most of the Philadelphia-area shops at the top of the list are still open — and doing brisk business.

Local gun shop owners and gun-rights advocates pushed back on Friday, calling the study fundamentally flawed.

Philadelphia Training Academy, for instance, came in second on Brady’s list, with 2,356 crime guns traced back to the South Philadelphia gun shop and shooting range.

But owner Jimmy Mastroddi said the Brady analysis doesn’t take into consideration that shops like his sell a much higher volume of guns than others.

“It’s an unfair number,” Mastroddi said, adding that his staff’s safeguards for preventing illegal sales “go above and beyond” industry standards. He said those measures include looking for signs that a potential buyer is communicating with someone else on a Bluetooth headset or by text.

“That is my first priority, to identify and dismiss any possible straw purchase,” Mastroddi said.

At Firing Line, a gun shop in South Philly to which 1,286 crime guns were traced, Gregory Isabella scoffed at the Brady study.

“If we did anything illegal, we’d have been shut down and not in business for 38 years,” Isabella said.

The federal Bureau of Alcohol, Tobacco, Firearms, and Explosives has found several violations over the years at Firing Line, and concluded at one point that it had “demonstrated willfulness in regards to facilitating the straw purchase of firearms,” according to an ATF document.

In 2019, Attorney General Josh Shapiro’s office launched the Pennsylvania Track + Trace Initiative, a collaboration with police departments across the state to centralize the tracking of illegal gun transfers.

The program relies on police departments to share crime gun data. While participation is higher in the Philadelphia region, more than half of Pennsylvania agencies are not yet sharing their recovered gun information.

“I have said for years that most crime guns come from a small number of stores,” Shapiro said in a statement Friday.

Shapiro, though, cautioned against drawing conclusions about individual sellers from the data, saying that a seller of guns that end up in crimes may also be reporting suspected straw purchasers to law enforcement, and that cooperation wouldn’t be publicly available.

Of the 66,104 total guns recovered in Philadelphia by law enforcement, the majority came from in-state dealers. The analysis traced 51% of the guns to Pennsylvania dealers, 28% came from dealers in another state, and the origin of 22% of the guns linked to crimes could not be traced.

“Most gun dealers are really honest and try to do what they can not to add to this problem,” said Heyne, of the Brady group. “It is a few bad actors that can ultimately have a dramatic impact on the market of illegal guns.

Kim Stolfer, president of Firearms Owners Against Crime, a Pennsylvania gun-rights group, called the study misguided. He said policymakers should focus less on gun sales, and more on stronger prosecution of gun crimes.

“If they were interested in stopping crime,” Stolfer said, “they’d be talking about how district attorneys don’t prosecute the people that are involved in crime now. Then they get back out of jail and commit more crimes.”

The ATF traces the guns used in crimes by using a serial number to track the weapon from manufacturer to point of sale. That information, though, is not public, largely due to an amendment that the gun lobby pushed through Congress in 2003.

Heyne recommended that Congress repeal the amendment, known as the Tiahrt Amendment, and require that gun trace data be made public. Transparency, he said, would allow state and local officials to better scrutinize problem dealers.

“The story that this report tells is the same story that those ATF reports were telling in the early 2000s,” he said. “And the gun lobby didn’t like the story that was being told. … This is a huge industry and there’s a lot of profit to be lost if the illegal market doesn’t exist.”

Pinpointing the problem dealers, Heyne said, and “stigmatizing the bad behavior” could seriously help stem the flow of illegal guns. Some of the problem shops, he said, need better support and scrutiny, but others need to be shut down entirely. Heyne said ATF is underfunded and understaffed, and as the sole federal agency with oversight of gun dealers, needs more resources to improve oversight.

Through public records requests and litigation, the Brady nonprofit acquired about 50,000 pages of gun dealer inspection reports from the ATF. Heyne said they show that when inspectors have time to look at gun dealers, they do a good job spotting violations and creating recommendations.

But, he said, “when those recommendations are given to their superiors, they’re often downgraded.”

The impact of that, he said, is that problem dealers often do not see repercussions beyond a warning letter, and their actions are not corrected.

Heeding God’s Call, a Philly-based gun-control group, previously organized a large campaign to shut down Colosimo’s. More recently, the faith-based organization has focused on state legislation.

But Bryan Miller, its cofounder and executive director, said the new report may inspire the group to pick their local organizing efforts back up.

“The problem has been no data,” he said. “So this report, from my point of view, is groundbreaking.”