From everything I have read today, the person in your original picture is Michael Brown - but NOT the same one who was shot.
As to this picture, I have no idea who either is and really don’t care.
I am not defending the thug in your original picture, nor am I defending the MB who was shot. I come from 3 generations of NYPD, and until shown otherwise in a particular situation I lean to defending LEO’s.
A retired LEO friend of mine, on another forum, pulled that picture(your first one) after it having been proven to him it it was not the same person. He also apologized for not having done his own due diligence in ascertaining the veracity of the photo he shared.
I guess I will have to see the same proof your friend saw. Jim Hoft of Gateway Pundit has been following this story very closely since he lives in St Louis. He has contacts that provide him information. Hoft has yet to pull the picture down from his site.