UC Davis forensic science program researchers testing new microscopic engraving technology on gun firing pins have concluded that while it is feasible, the technology did not work well for all guns and ammunition tested.
“My study shows that while this technology works with some firearms, it also has problems in other firearms,“ said UC Davis forensic science graduate student Michael Beddow. “At the current time, it is not recommended that a mandate for implementation of this technology in semiautomatic handguns be made. Further testing and analysis is required.“
Todd Lizotte of ID Dynamics, located in Londonderry, N.H., developed a way to use an ultraviolet laser to engrave microscopic markings onto firing pins, similar to how codes are engraved onto computer chips.
When the trigger is pulled, the micro-stamped firing pin will hit the primer of the cartridge case and leave the marked code on it. The idea is that the ejected cartridge can be matched to the gun from which it was fired, which is the premise for the Crime Gun Identification Act of 2007.
Governor Arnold Schwarzenegger passed the Assembly Bill 1471 in October 2007, requiring all new models of semiautomatic pistols sold in California after Jan. 1, 2010 to be engraved with a micro-stamped code in at least two areas of the “internal surface or internal workings parts of a pistol.“
Fred Tulleners, director of the Forensic Science Graduate Group, discovered issues with the process.
“When trying new things, we want to really investigate it,” he said. “We found it is technologically flawed.“
Tulleners is the former director of crime labs in the Sacramento and Santa Rosa areas as well as the former director of the California Criminalistics Institute.
Beddow tested the micro-stamped firing pins of six different semiautomatic handguns, two semiautomatic rifles and one pump action shot gun at the California Criminalistics Institute and the California Highway Patrol Academy.
Each firing pin contained three different types of codes: an alpha-numerical code on the tip of the firing pin surrounded by a gear code with a bar code going down the length of the firing pin. Recruits fired 2,500 rounds of ammunition to test the durability of repeated firing, Beddow said.
The ammunition was labeled in numerical order and shot through various guns. The cases were then collected in order to see potential change in the legibility of the characters. The firing pins themselves were photographed at intervals to determine if there had been any changes.
“We had mixed results. By and large, [in] most cases, the bar codes and gear codes did not succeed in impact. It has to do with how the firing pin operates. Sometimes they do multiple hits,“ Tulleners said. “For instance, [in] the AK-47 gangs use, the firing pins make multiple hits [to the cartridge].“
Multiple hits from the firing pin will mar imprints to the cartridge, thus nullifying the effectiveness of the micro-stamping. The most successful code was the alpha-numerical code.
“The alpha-numerical code provided the best quality of the numerical codes. The quality of forgeability of the impression ranged from firearm to firearm; every gun shoots differently and functions different so the legibility was different,” Beddow said. “Bottom line, the technology is feasible. However, [it] does not function equally.“
The study was supervised by David Howitt, a UC Davis chemical engineering and materials science professor, and was completed and informally released a year ago. The study was peer reviewed by six external reviewers, the National Research Council among them. This March, the council came out with the same conclusions in their report: more research would be needed to prove that firearms identification rests on firmer scientific footing.
Other concerns with the new technology include the cost of implementing codes on all firing pins and how beneficial the technology will be. According to Tulleners, there are three types of shootings: crimes of passion, professional hits and assassinations (which are less solvable) and gang shootings.
“This research conceivably affects gangs. However, we routinely link cartridge cases to guns,” Tulleners said. “Without DNA, gangs are notorious for passing guns, and just because you link a cartridge does not mean you’ll find who did it. Gangs can deface the firing pin or buy a whole bunch of firing pins and replace them.“
As for the cost of the firing pins, Tulleners estimated the engraved firing pins would cost $7.87 or $6.72 each, which is a very conservative estimate. “There is no real benefit to society, and the money is better spent on other progressions in society,” he said.
WENDY WANG can be reached at firstname.lastname@example.org.