This had nothing to defend your imaginary defend thd police mentality. And no one is holding him to law enforcement standards.
It's illegal to kill someone, even by accident. There are exceptions, such as self-defense. But even self-defense has limitations.
2. A person may not use deadly physical force upon another person under circumstances specified in subdivision one unless:
(a) The actor reasonably believes that such other person is using or about to use deadly physical force. Even in such case, however, the actor may not use deadly physical force if he or she knows that with complete personal safety, to oneself and others he or she may avoid the necessity of so doing by retreating; except that the actor is under no duty to retreat if he or she is:
(i) in his or her dwelling and not the initial aggressor; or
(ii) a police officer or peace officer or a person assisting a police officer or a peace officer at the latter's direction, acting pursuant to section 35.30; or
(b) He or she reasonably believes that such other person is committing or attempting to commit a kidnapping, forcible rape, forcible criminal sexual act or robbery; or
(c) He or she reasonably believes that such other person is committing or attempting to commit a burglary, and the circumstances are such that the use of deadly physical force is authorized by subdivision three of section 35.20.