Does anyone have a link to a summary of the actual events?

Well, I don't think someone else - other than the documentary maker - would have looked into the story (it's not known here in Brazil).
As for your questions, these are the answers (as far as I understand the documentary and all the pieces of news that I followed here):

a) Yes. I know not many people will like to read that, but robbing passengers on a bus is a common practice here in Brazil, not only in big cities but especially in the outskirts. So, I guess it was his original intention, indeed;

b) Actually, a passenger suspected Sandro of robbing the passengers. She got off the bus and called the cops;

c) There were more passengers on the bus, who got off it as time went by. He didn't really focus on just 04 of them because he was totally doped. It seems to me he just couldn't figure it out;

d) Pure lack of competence.

The DVD has more interviews and special feature on the situation. But as for street kids in general Rio has a good 4 Million alone.

There are lots of different point of views to look at the street kid issue, there are the slums, then there's what happened when all the kids where shot at the church and there's kids living on the street.

Another good film that somehow deals with the issue is "City of God" - the film is also based on a true story but the DVD for City of God has a documentary on the real life slums in Rio today. How drug dealer rule the hills and cops are fighting them.

That we really have to ask these basic questions re: what really happened is a testament to the piss-poor quality of this so-called "documentary", lol.

1/10

- don't worry, that's just my signature there.