How the ATF follows the history of guns used in Indiana crimes

So 13News traveled there to find out how it all works. And you might be surprised when you see for yourself.

"We're sitting on about 28,000 boxes of records that are waiting to be processed," said Neil Troppman, program manager at for the ATF’s National Tracing Center. It is the only crime gun tracing facility in the country.

"We treat every request that comes through the door as an important piece of information that may help to solve the case,” Troppman said.

Police send the details of the gun, and using the serial number, the ATF begins the trace, starting with the manufacturer, then who sold it, who bought it and where.

Essentially, the gun's life story is traced to figure out who had it last. They are details every licensed firearms dealer is required by law to keep on location.