What about something like: extremely dangerous, wanted criminal is on the loose. He's known to be a in a large city, and you use facial recognition to find/track him before he can commit a bombing or something like that.
Or related to that: Let's assume you really hate the Jews for, I dont know, existing maybe. Why not track them all down and put them in camps? It's not like they can hide from you you, you know where everyone is all the time after all.