Crime rate is a decent metric, but I feel it's too indirect to be useful. If they do change, there are a lot of possibilities that could explain it: police aren

Crime rate is a decent metric, but I feel it's too indirect to be useful. If they do change, there are a lot of possibilities that could explain it: police aren't enforcing silly laws, that laws are reasonably legislated, police have been corrupted by bribery, and so on.