LOUISVILLE, Ky. (WDRB) — Louisville Metro Police is solving more murders than they have in several years. Investigators said a federal ballistic database is helping them generate leads faster.
The technology is called NIBIN — the National Integrated Ballistic Information Network. Run by the Bureau of Alcohol, Tobacco, Firearms and Explosives, the system connects shell casings recovered at crime scenes to the gun that fired them and to other shootings linked to that same firearm.
"The technology for investigators today — it'll blow your mind," said ATF Special Agent in Charge John Nokes.
Tracy Starks is one of LMPD's three NIBIN firearms technicians. The process begins with recovering a shell casing from a scene or test-firing a recovered gun. Starks examines the casing under a microscope before placing it into an imaging machine that captures the unique markings left on the casing when it was fired.
"It's just like a fingerprint — every fingerprint is different, every weapon marking is different," Starks said.
Those images are sent to one of ATF's two national correlation centers, located in Huntsville, Alabama, and Wichita, Kansas. Within 24 to 48 hours, investigators can learn whether a casing matches others and whether it connects to other crime guns or crime scenes. ATF says the only guns in the database are those connected to a crime.Â
Nokes said the same gun is frequently linked to multiple crimes through the system.
"It's not unusual to see the same gun be used five, six, seven times — we are working some now that are beyond a dozen," Nokes said. "Every single day there are leads connecting crime scenes we wouldn't know otherwise."
Last year, LMPD processed about 3,600 pieces of evidence through NIBIN. So far this year, that number is already at 1,900. In Kentucky, there have been 7,500 NIBIN acquisitions total, with 4,100 recorded year-to-date.
Nationally, about 35% of the time a casing entered into NIBIN links back to another crime scene.
LMPD's homicide clearance rate stands at 56% so far this year — the highest it has been in several years.
Starks said a single shell casing can be the break investigators need.
"Even if it's just a tiny piece of the puzzle, you're a part of that — so it's very rewarding," Starks said.
Copyright 2026 WDRB Media. All Rights Reserved.
