Most people know about the reliability of fingerprints.
Project staff use digital cameras to photograph bullets and cartridges and scan them into a computer, where they are analyzed by a software program and stored in a database waiting for bullets or cartridges fired from the same gun to be scanned at some future point. What used to take weeks or months for analysts to determine what could be used as evidence now can take only a few minutes. Detectives who recover bullets from a crime scene in one state can compare their evidence with bullets from crime scenes across the country to find suspects. Sauer likens the database of images to a giant Rolodex that people can use to come up quickly with the most likely candidates for matching crime evidence. The latest innovation is ATF's effort to talk with gun manufacturers, who will image their inventory before it goes out.