And the cop's defense attorney would say that it was adrenaline, that it was the heat of battle due to being hit by and struggling with Brown, that he had tunnel vision, and was following procedure when it comes to a charging and violent person.
That's how it will work out. And the burden of proof will be on the prosecutor.
likely....
because as we all know, there was no urine or blood taken i assume.....because......well, cops are a protected species.