(Talking about the Sammy Yatim streetcar case, here.)
No -- the cop (james forcillo) is already charged with 2nd degree murder. So the prosecution has to prove (i) that the homicide took place, (ii) that JF had formed the intention to kill SY, (iii) that JF actually did deliberately and purposefully commit the act that resulted in SY's death.
All those elements are unmistakably clear from the video. Obviously, the cop can't argue that someone else committed the homicide. Nor that it was an accident.
There's no premeditation -- but they don't need to prove premeditation for 2nd degree murder.
From the video, it seems inescapable that JF is guilty of 2nd degree murder. I assume that will be proved beyond doubt, straight off the bat, in his trial. JF's only hope is that he can prove he was acting in self-defence. And he must prove that he was -- the prosecution does not have to prove that he wasn't.
Naturally, the court and the jury will be disposed to believe that any officier who shoots someone was indeed acting in self-defence. But this time, the offiicer must explain how the facts that are evident from the video can be squared with his theory of self-defence -- which is going to be tough.