This post is also available in: heעברית (Hebrew)

Microstamping is a proprietary ballistics identification technology. Now gun control advocates in the US are making a new attempt to force the gun industry to comply with California’s unique law requiring individual identifiers on all bullet casings, a mandate that has been toothless since it was approved in 2007.

The law requires gun manufacturers to adopt micro-stamping technology on new types of handguns introduced in California. The intent was to imprint a unique set of microscopic characters on all cartridge casings when weapons are fired, linking bullet casings to the guns that discharged them.

Gun makers have said the technology is unreliable and to get around the law have not introduced new gun models in the state since the law was passed.

New legislation would expand the law to include weapons used by law enforcement, which are currently exempt. The thinking is that forcing police officers into the marketplace would prompt manufacturers to improve technology so they can sell the weapons to members of law enforcement.

Mark Oliva, spokesman for the National Shooting Sports Foundation that is the trade association for the firearm industry, said microstamping is an “unworkable technology.”

It could take up to 10 bullet casings to piece together one complete digital identifier that could determine the weapon that fired the bullets, he said. Moreover, the technology could be easily defeated by sanding the microstamp off the firing pin in much the same way that criminals currently erase guns’ serial numbers.

Last year, California enacted a law easing the requirement for two microstamps on each shell casing to one. Another bill this year would keep the two-stamp requirement in place until July 2022.

No other U.S. state has either the microstamping law nor the law enforcement requirement. Associations representing sheriffs, police chiefs and rank-and-file officers said they were reviewing the proposed legislation, according to abcnews.go.com.