An additional conjecture I’ll throw out is that is that as crime declines, it frees up police to investigate crimes and catch non-violent criminals who might not be caught if the police were busy dealing with more serious crime.

I still remember this anecdote from an article several years ago headlined “As crime dries up, Japan’s police hunt for things to do” [1].

> THE stake-out lasted a week, but it paid off in the end. The tireless police of Kagoshima, a sleepy city in the far south of the country, watched the unlocked car day and night. It was parked outside a supermarket, and contained a case of malt beer. Finally, a passing middle-aged man decided to help himself. Five policemen instantly pounced, nabbing one of the city’s few remaining law-breakers.

Can you imagine this happening in San Francisco?

[1] https://www.economist.com/asia/2017/05/18/as-crime-dries-up-...