California police are using biometric technology to track suspects by scanning their fingerprints, tattoos, and photographs. EFF, the Electronic Frontier Foundation, conducted a study to determine the fingerprinting technologies and biometric methods being used by law enforcement, and they received responses from 30 different organizations and nine police departments.

About half of those California police departments scan suspect faces using facial recognition, and the other half use fingerprint scanners to crosscheck them with a larger database. Only one of the CA agencies uses biometrics to detect tattoos, but this technology is still on the rise. Many of the organizations contacted by EFF have not acknowledged or are still processing the request to information.