I'll disagree.He did not shoot on sight. However, it could lead a reasonable officer to believe he was reaching for a weapon even though one was not found later.
He spots someone fitting the description cutting between buildings, parks and runs to the other side of another building... reporting in on the run.
He rounds the corner, yells "get on the ground, get on the ground" and then commences to firing 4 rapid shots within THREE SECONDS of rounding the corner (1:28 - 1:31). First shot ONE SECOND after his commands.
At the break of that first shot, IMO, there is only one person who has a legitimate fear of imminent death or serious injury... and it ain't Officer Rootin' Tootin' Shootin' Cowboy.