Yesterday’s NYT ran an article summarizing one study drawn from the MacArthur-funded Project on Human Development in Chicago Neighborhoods. Dr Felton Earls finds that strong social capital (“collective efficacy,” in the study’s parlance) underlies both the “eyes on the street” and “broken windows” theories on crime prevention. In other words, strong neighborhood social capital creates safe neighborhoods and positive school outcomes:

In a landmark 1997 paper that he wrote with colleagues in the journal Science, and in a subsequent study in The American Journal of Sociology, Dr. Earls reported that most major crimes were linked not to “broken windows” but to two other neighborhood variables: concentrated poverty and what he calls, with an unfortunate instinct for the dry and off-putting language of social science, collective efficacy.

“If you got a crew to clean up the mess,” Dr. Earls said, “it would last for two weeks and go back to where it was. The point of intervention is not to clean up the neighborhood, but to work on its collective efficacy. If you organized a community meeting in a local church or school, it’s a chance for people to meet and solve problems.