Two comments:
1. US police are not peace officers - they are ex-members of the military force and act as such - shoot first and ask questions later. In some cases it might be justified by the violent nature of the US society, but the "collateral damage" of such policing tactic is high.
2. It is utterly stupid to resist or otherwise provoke a police officer - again they are not peace officers but paramilitaries sent out to a combat zone, and will respond with deadly force to any resistance or perceived threat they encounter. Again, in many cases using such force is justified, while in other cases it is not - but the paramilitaries have no way of telling which is the case. Therefore it is utterly stupid to provoke an armed paramilitary who has been trained to kill. The best strategy is to do what they say and then argue your case in courts. That gives one a much better chance of defense, especially for those with money.
Wojtek