The role of gun thefts in crimes in is a big, complex issue in the U.S., and to cover it, single-topic gun issues news site The Trace needed some help.

Last week, the site published Missing Pieces, the product of a deep, yearlong investigation into how stolen firearms have been used to commit crimes. The numbers are staggering: After poring through the data, reporters found more than 23,000 stolen firearms recovered by police between 2010 and 2016 — most of which had been used in crimes, including carjackings, kidnappings, and armed robberies. Gun owners had bought guns to fight off crime, but were unwittingly helping people commit it.

The Trace didn’t reach these findings alone. To produce the story, the organization teamed up with over a dozen local NBC television stations, which each took the lead in chasing down data in their respective markets. The partners together collected more than 800,000 records from 1,054 law enforcement agencies in 36 states and the District of Columbia. It’s a valuable, if incomplete, set of data that The Trace hopes other reporters and researchers can build on. Along with its reporting, the organization also uploaded the entire dataset to its website for free.

12/ Until the ATF is allowed to share national data, the public will never understand the full extent of the problem. To help close the gap, we’re making all of our data available to reporters and anyone else who’s interested.

— Daniel Nass (@dnlnss) November 20, 2017

Offering that data is part of The Trace’s mission “to improve quality of reporting on this issue across the board, even if we don’t see any traffic come back to us,’ said Akoto Ofori-Atta, its senior editor. “What’s important is we give as many people as possible access to good information about the issue. Opening up the data is an extension of who we are and how we see ourselves in the journalism world. We want to make sure reporters have what they need to do this work and see us as a valuable resource to help them do it.”

Trace editorial director James Burnett said that the organization owes much of its approach to partnerships and open data to ProPublica, which has pioneered similar partnership models for nearly a decade. “We have to give credit where its due to all the others who have a practice of doing things like this,” he said.

My colleague, @BrianFreskos, carrying less than a tenth of the records he scoured for this yearlong investigation, @teamtrace‘s biggest one ever, and the first of its kind. Read it! https://t.co/I70exs5dpf pic.twitter.com/qunFmC72I2

— Akoto Ofori-Atta (@KO_616) November 20, 2017

Missing Pieces doesn’t focus exclusively on data, however. Brian Freskos, the lead reporter on the project, and local NBC colleagues talked to people like 19-year-old Aysia Quinn, who was shot by a stray bullet from a stolen gun. Burnett said that The Trace’s gun coverage would not be complete without it spending time talking about the human dimension of the issue, which ‘is important to keep in mind even as we bring in new data in to the public realm on the topic.”

This coverage has helped cement The Trace’s status and authority among other news organizations covering gun issues. Since its launch, the site has worked with more than 46 news organizations (including The Guardian, The Tampa Bay Times, and The New Yorker), some of which have partnered on reporting projects, while others have merely republished The Trace’s reporting. The site, now at 12 full-time staffers, has been cited over a thousand times since its launch in 2015, said Ofori-Atta.

The Trace’s coverage of gun theft ties into its larger mission to cover the kind of gun stories that don’t draw the big headlines at mainstream news organizations, which dial up their gun coverage after mass shootings but spend comparatively little time on the topic when interest fades. The Trace in contrast, spends the bulk of its time covering the “causes, origins, and contributing factors to gun violence that makes up 98 percent of fatalities and includes multiples more of non fatal shootings,” Burnett said.

At the same time, The Trace — which was initially funded with money from Michael Bloomberg’s Everytown for Gun Safety pro-gun control group — has also tried to be attuned to the small windows of increased public interest in gun issues that arise in the wake of mass shootings. After October’s Las Vegas shooting, for example, the site posted a tweetstorm putting the event within the context of the gun violence that occurs daily around the U.S. The response was illustrated with charts, data, and links to The Trace’s previous coverage.

1/The Trace launched just after the Charleston church shooting. We’ve covered several events like Las Vegas, where death toll is 10+.

— The Trace (@teamtrace) October 3, 2017

Burnett compared the site’s role in these situations to that of the typical trade publication, which day to day has an “expert super-engaged audience,” but which can occasionally broaden to “people who are only going to be interested when we’re covering the story of the week. We have to use the moment to give them the big picture.”

As The Trace wrote at its launch: “We do bring a point of view to the issue of gun violence: We believe there is too much of it. But our focus is on a related problem: the shortage of information on the subject at large.”