It's beyond irresponsibility - it's actively malevolent. There unfortunately are police officers, as demonstrated by recent high profile killings by police, who will use the thinnest of pretexts, like suspicion of paying with counterfeit bills, to justify the use of brutal and lethal force.

If such people are empowered by a facial recognition match, what's to stop them from similarly using that as a pretext for applying disproportionate brutality?

Even worse, a false positive match triggered arrest may be more likely to escalate to violence because the person being apprehended would be rightfully upset that they were being targeted, and appear to be resisting arrest.