Noah Smith has four suggestions for reducing crime:

1. Lead abatement.
2. Drug decriminalization.
3. Prison education.
4. Community policing.

I agree with all four suggestions, but I want to focus on community policing, especially this part:

One very simple thing cops can do is to get out of their patrol cars and walk around. High-quality evidence shows that foot patrols cut violent crime. Simply having police around deters criminals, but it also allows communities to have repeated positive interactions with the police, building relationships that cut crime in a number of ways.

This was one thing the police in Boston did well–and it’s reflected in their crime numbers: they walk around (and my anecdotal impression is reflected in real policy decisions). In D.C., I live a block away from a police substation, and I never see police on foot, except when they’re walking to their cars. One problem, however, is that many of the high crime areas aren’t very dense (this isn’t transitive, as many low density areas in D.C. are also low crime areas), so foot patrols aren’t a great way to respond. As Alissa Walker put it last year, “One reason is the way our cities have grown—the distance that some cops would have to cover on foot would make it statistically impossible to keep the peace.” Nonetheless, D.C. should consider getting police out of their cars and onto the street whenever possible..