You are talking like this a white/black thing. Every media outlet always finds an angelic looking picture of the victim and a nasty looking one for the perpetrator. It has nothing to do with colour of skin.
This murder did have something to do with colour of skin though, the way you are painting it though is that the media only grabbed hold of it because he was black, which is false. They grabbed hold of it because the state officials tried their very best to bury it and only when the video was released by a lawyer were they left with no choice but to do something. That may well be because he was black and the killers were white, we will have to see what comes out, it might just be because they knew the father but regardless from the first interaction with the police to the district attorneys, the killers were protected and the victim was blamed. It shouldn't take a video being released months later by a lawyer to get justice.