Do you need flock to do this for you, though? I have cameras around my property, and they catch everyone entering and leaving my subdivision. If the police need access to the recordings, they can get a court order or ask nicely. What I don't do, is share the feeds with everyone willy-nilly so the police can cast wide dragnets and do god-knows-what-else with the data.
By the time you get a court order. The trail has gone cold at least that's what the police said at our HOA meetings. Maybe they're getting paid by big money to say these things but these were not head of police people. Low levels coming to HOA meetings.