From the street to the lab: Chicago police sort and test a vast amount of weapons recovered as they combat violence

The technicians also submit a sample of shell casings, whether they’re from a test-fired gun or one from a crime scene, into a computer that uploads high-resolution images of the evidence into a database for the National Integrated Ballistic Information Center, or NIBIN, a program that has been around since the 1990s and is administered by the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives.