Oh, in that case we don't even need parallel construction anymore. Why bother, if it doesn't matter how you got your evidence then any evidence is good.

Just use whatever dragnet method you already have in place and phone it in. Subpoena google for all searches done in all cities and go round up the folks whose searches match the names of the victims.

I'm sure your going to get a fantastic conviction rate.

A society like that already existed: It was called East Germany and petty crime there was nearly non-existent. What crime there was was mostly corruption and went unpunished (who will watch the watchers).

Former East Germans seem to prefer the society they have right now.