Amnesty's lastest report on Brazil "We have come to take your souls": the caveirão and policing in Rio de Janeiro is another in a long line of reports concerned with policing the favelas. This summary from a similar report from 2005 contains a compelling rundown of statistics on the on-going violence in these communities. Here's an action related to the current report: Link
At our last meeting I recalled that there is a documentary attached to the City of God DVD about violence in the favelas. I've confirmed that-- it's called Notícias de uma Guerra Particular. Of course I recommend City of God itself, as well as the documentary Bus 174 which I saw at the Amnesty International Film Festival a few years ago.