You defend your life
You defend your family
You defend your propery
You get arrested & prosecuted
That is just sad, that it has turned this way in America,
Where criminals have more say & rights than you
The problem here is that you are assuming the shooter is necessarily the good guy, that the shootee is necessarily the bad guy, and that such information is clearly obvious to law enforcement.
After a crime occurs and law enforcement arrives, they are often faced with a myriad of information, some of it conflicting, some of it potentially evening appearing to be admissions of laws broken by the purported good guy or desbribed by witnesses. Sometimes the story given by the purported good guy doesn't match the evidence.
That the purported good guy gets arrested as has to go through the whole legal process is called "due process."
As noted in OK, you won't necessarily get arrested. I would not count on not getting arrested. In fact, I would go ahead and assume that you will likely be arrested until which time you make bail or the cops figure out that you aren't the bad guy. Hopefully, that will be resolved quickly.