The guns were seized during roughly 125 narcotic investigations throughout Los Angeles County over the last two years, but authorities still had an important question about them: How many other crimes were the weapons connected to?
On Friday, federal agents took a key step toward an answer.
Agents test-fired the firearms at the Glendale Police Department's gun range to catch the shell casings. The agents plan to analyze and upload information about them to a national database of ballistic evidence managed by the Bureau of Alcohol, Tobacco, Firearms and Explosives.
The weapons numbered more than 150 and included semi-automatic pistols, long rifles and shotguns. A match to evidence detailed in the database could give investigators a key piece of evidence in an unsolved shooting somewhere.
"Each firearm leaves a very distinct marking on the back of a shell casing, it's like a fingerprint," said Chris Bombardiere, who supervises the ATF Crime Gun Intelligence Center in Los Angeles. "Once they start going in we have a 24- to 48-hour turnaround to where we start linking these firearms to other crimes that occurred where shell casings were picked up."
Nationwide in fiscal year 2015, federal authorities entered into the database 76,534 casings that were recovered from crime scenes and 130,004 casings that came from test-fires of retrieved weapons. That led investigators to 7,866 matches, according to the ATF.
"The handguns and the long rifles, they tend to be transient between the criminals. So not one criminal holds on to a gun for very long," said Brian Rose, a special agent who supervises the Los Angeles Interagency Metropolitan Police Apprehension Crime Task Force, which seized the guns that were test-fired on Friday. "So there's a good possibility that one of these guns has been used in a previous crime."
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