Neither of these assertions has yet been proven. There are other theories that explain the actual known facts, though not perhaps as well.
For instance, if the cop has a broken head bone, it is possible Brown gave that to him while legitimately defending himself against an unprovoked attack by the cop. Admittedly, not very likely.
We also have, to my knowledge, no indisputable evidence that he was charging the cop when killed. Though I suspect that's exactly what happened, it hasn't been proven yet.
If the black can jump to conclusions, so can the white.
Some conclusions seem more likely than others as well.
A further conclusion is that Brown’s accomplice was full of sh!t...surprisingly.