The officer was absolutely in the right. Would there be this much debate had the guy went for them with a knife or similar deadly weapon? The dog presented an immediate risk to the officers and others around them.
Also, the owner is the reason the dog is dead.
Gutted I'm missing this as I rarely miss a chance to see them, I'm in Barcelona that week, though then back on the Saturday for The View plus very special guests The Stone Roses & Primal Scream