Actually, one should ask why was this person resisting. Watch and see where his hand is before being struck. Appears as if he was preparing to strike the officer, maybe the officer was attempting to strike the subjects had to avoid be punched in the face. Should the officer have waited to get struck first? Or maybe I am totally wrong and this was excessive. Might be wise to wait until all information is in prior to crucifying this officer. And all you armchair warriors can relax until all facts