[ahelwer]

It is legal for a PI to tail you not because of the lack of expectation of privacy in public, but because it is impractical to have PIs tail everyone all the time in public. People are generally okay with targeted surveillance. Mass surveillance is the issue. Quantity has a quality all of its own, as they say. There has been a court case which addresses this issue[0].

Any technology which searches for fugitives will necessarily scan everyone. There is no such thing as targeted facial recognition, it can only work by mass surveillance.

[0] https://www.nytimes.com/2019/04/17/opinion/data-privacy.html

[philwelch]

You're assuming facial recognition would necessarily be the moral equivalent of "[having] PIs tail everyone all the time in public.". But for that to be the case, facial recognition would have to scan every face it sees, store that face, and then cross-reference every other face it sees against every face it has ever stored.

I'm suggesting a far simpler use case: It scans your face and if you don't match any of the fugitives it's looking for, it forgets about you. I think this use case is far more likely because it's a lot simpler and cheaper to pull off. And that's a big difference.