The DA (who is a widely respected person) is saying that in any situation where a suspect has run it is policy to draw your weapon as the officer did. From a rules perspective, he did the right thing. It is also policy to fire two shots, and the officer only fired one which suggests (to the DA) it was an accidental discharge and not intentional. I think that is further supported by the fact that after the gun goes off, he holsters it rather than keeping it on the situation - he doesn't trust it anymore.
However, he doesn't appear jarred from the shot, nor does his demeanor change. And he waited a long damn time to report the shooting after it happened. And he does not appear to announce himself or give the guy any orders but later announced the dude he shot in the neck "refuses to get out."
All very odd. Pretty sure this is going to end in a lawsuit.