I've never lived in anything resembling a rough neighborhood, but I think I can sympathize with the people who live in these neighborhoods who are frustrated and depressed at their powerlessness against the violence.
One of the main problem, I believe, is that the major offenders in these neighborhoods only fear violence, disregarding attempts at non-violent intervention. And since asking for help from the police can result in being labeled a snitch, which can be as good as a death sentence, possibly extending to family members, I can understand why most people just stay quiet. Unfortunately, this silence contributes to another significant problem: the ineffectiveness of the police--not to say that they aren't doing their best with minimal community support and funding.
It's a difficult problem that doesn't have easy, black and white solutions. The Interrupters, however, seem to have practical strategies for diffuse the violence which are far more effective than the threat of incarceration, which obviously doesn't work. I believe it was Cobe Williams who said, "We aren't in the good and bad game; we aren't in that Drama." With the exception of a few extreme cases, people aren't "bad," they're just doing what they think they need to do in order to survive, reacting in a ways they're conditioned to. By approaching these people as people, not bad people, The Interrupters are able to get through where others are defensively turned away.