That is a wikipedia-type sentence, not a law.
Dorner had used deadly force on the officers on the scene.
He still was armed and refusing to surrender.
He had killed a deputy when he tried to bolt the house earlier.
He was still armed and represented a lethal threat to officers on the scene.
Deadly force was justifiable until such time that he surrendered.
What if a sniper spotted where he was in the cabin and shot him dead that way? Would that make him less dead? Dead in a way more satisfactory to you?
ROFLMAO !!!! Surely you don’t think those LEOs were going to allow that now did you? Deadly force? Who was in danger if the LEOs just stayed back and starved him out?