I just read that the person with Brown, Dorian Johnson, admitted to the FBI and local police departments that it was them on the tape.
http://www.msnbc.com/msnbc/ferguson-police-name-michael-brown?cid=sm_m_main_1_20140815_29822566
I was under the impression that the officer just stopped those two cats for no reason, and some ugly shyt went down. After seeing these pictures and article, the officer appeared to have probable cause to question Brown and Johnson on the street. Now, Mr.Brown had a right to due process and to at least defend himself in court though, not be executed in the street. This isn't Judge Dredd.
Either way, the cop would have probably escaped being found guilty in a court of law, but I doubt he even gets charged now. It was also going to be his word against theirs, and now it will be the word of a cop with no blemishes on his record against what will eventually be someone charged with robbery and one dead suspect of a robbery. Only hope for change now is that the FBI digs something up that was covered up. We'll see.