Point being missed here is that police can not act with physical force from verbal taunts or jestures deemed offensive. Flipping the bird/one finger salute or for brits, its the two fingers forfinger and the middle finger (of historical significance toward the French army).

Now if one were to approach an officer and start to scream at the officer in the face... A grey area.

Or if you were to raise your hand and ready to make a physical contact with the officer, then its all's fair on the part of the police.

I'm just suprised that the 22 or was he a 23 year old even managed to get on the force. You would think he would have been rejected on psyche profile. Wrong temperment...