This shit is fucked up. I am not gonna defend what the cop did, because its completely unexcusable.
But I think some people might not really realize exactly what a BART cop is. BART gets federal funding, and this makes a BART cop technically a federal agent. They are not like a mall cop or some rent a cop security guard, you do not want to fuck with them. I used to think that they were like some fuckin rent a cop type shit, but they are definitely not. Now I dont know what set the situation off, and clearly the cop was out of line, but maybe if these guys had gone into the situation thinking of BART cops as federal agents, the whole thing could have been avoided.
Again I am 100% not defending the BART cop. That motherfucker deserves life in prison or worse, but I think that this situation could have been avoided if the dude and his friends actually knew the big picture for the situation.