Interesting, and I don't wholly disagree with your point of view, I'm mostly just thinking it through. I really agree that technically it seems like the best option, a few days in jail at most, but it still seems to go against our rights, and eroding those seems to be too easy anyway.
And where do you draw the line? You said anytime you shoot, does that mean other ways of killing people would not result in the same actions, like hitting someone over the head with a Rick, or stabbing with a knife.
What about when someone claimed they did not shoot the person?
And do we really want to put someone in jail when it is completely obvious they were the victim? What about when the victim sustains injuries, do you handcuff them to their hospital bed as we would a criminal?
Practically it seems like a good rule 99.5% of the time, but what about that last sliver, their rights count for something.