1. The police officer stopped Brown because, according to the Ferguson police chief, he was walking down the middle of the street blocking traffic. There is some speculation that Officer Wilson stopped Brown because he was a suspect in a robbery earlier that day, however, these rumors turned out to be false.
2. So was the shooting legal? Two Supreme Court decisions from the 1980s set a precedent for deadly force when used by cops. Basically, deadly force is justifiable by law when the police officer needs to protect their life or the life of another innocent party, or there is the threat of death or other serious bodily harm to them. The second circumstance is to prevent a suspect from escaping, but only if the officer has probable cause to think the suspect has committed a serious violent felony and it appears to be necessary to prevent escape. The St. Louis County Police Department is conducting an investigation of the shooting.
3. Right now in Ferguson, residents are protesting as to what they feel is unfair treatment of the black community. Police are using military grade hardware like tear gas, rubber bullets, and mine resistant vehicles.