Stamping on guns

New technology to link cartridge cases to guns by engraving microscopic codes on the firing pin is feasible, but does not work well for all guns and ammunition tested in a pilot study by researchers from the forensic science program at UC Davis.

More testing in a wider range of firearms is needed to determine the costs and feasibility of a statewide program of microstamping, as called for by proposed state legislation, the researchers said.

The technology developed by ID Dynamics of Londonderry, NH, uses a laser to cut a pattern or code into the head of a firing pin. The method is similar to that used to engrave codes on computer chips. When the trigger is pulled, the firing pin hits the cartridge case or primer and stamps the code onto it. In principle, the spent cartridge can then be matched to a specific gun.

If successfully implemented, microstamping would be one additional piece of evidence for investigators to gather in building a criminal case, said Fred Tulleners, director of the forensics program at UC Davis. Tulleners was formerly director of the California Department of Justice crime lab in Sacramento, as well as the Sacramento and Santa Rosa county crime labs.