Police use of facial recognition systems are coming under some media and civic attack- such as San Francisco where they were banned, because they potentially can recognize wanted criminals, illegal aliens and fugitives from the law that might otherwise pass unrecognized by a patrolman. The expert systems are an upgrade to fingerprint and I.D. scans that policemen can employ to verify that a possible suspect is or is not already wanted.
With so many tens of millions of undocumented people in the United States the possibility that a policeman will remember the face of some hundreds of thousands of fugitives from the law when encountering one is non-existent. Facial recognition systems are about the only way law enforcement people can sort through the bins of billions of individuals that live in or may travel through the United States each year.
Lawless cities that would prefer to allow terrorists and law breakers of various kinds to drift through the masses incognito are not helping to secure public safety at all in banning face recognition systems.
Certainly democrats could abuse the system and track people as ruthlessly as corporations track smart phone locations and with rtf scanners and sales record follow the location of many citizens already. It is the private sector corporate world with the use of face recognition system that has the greatest capacity to abuse the data. While law enforcement agencies use the technology to sustain public safety the corporate world already has the ability to use it for whatever critical collusions or scientific purposes they like without public review. Public review of law enforcement uses of face recognition technology should exist in camera each year to confirm that it isn’t being used with nefarious application as might a zodiac killer use the technology to sort out and track his victims, or a very old and rich University study society to learn who it prefers to delete economically.