I don't think you know shit. In a lethal force encounter I am legally entitled to defend my life with lethal force. I have no legal obligation to disable, wound, give a 2nd chance, or do what Jesus would have done. I will shoot until the threat is neutralized. That could take anywhere from one shot to a full mag depending on the situation.
Assigning arbitrary round counts and saying "x rounds is all you need and anything more is overkill" is one of the stupidest things I've ever heard. Every situation is different. If someone's coming at me with a knife, maybe a double or triple tap would do it. If we're wrestling around point blank and I just managed to reach my CCW, I'm going to put all 8 rounds into my attacker to be sure.
The only way I could get a lawsuit is if there's evidence of overkill, like he was on the ground dead and I went up and emptied the rest of my mag into him. Fact is, if I ever have reason to draw and fire rest assured it will be a legally bulletproof situation.
If the victim has several rounds in a combat effective center body mass, falls to the floor and you stop shooting, this is fine. However, if I then proceed to shoot them in the head while they're on the floor and the ballistics prove that I deliberately shot them two separate times with separate trajectories, then yes. I am going beyond simple self defense.
I think Alkemyst is confusing me with a moron. And no, there are numerous reports of police encounters (the FBI has done research and compiled statistics on combat 'shots fired', wherein an officer's average hit % at 10 yards was less than 4% of rounds fired) where the officer puts 7+ rounds center mass into a perpetrator with no noticeable effect and then was shot 2-3 times and killed while the criminal survived.
2-3 rounds is just 2-3 rounds, it means absolutely nothing. Outside of a critical shot to the spinal cord that shuts down motor control, adrenaline will keep a person functioning at nearly 100% for minutes even with mortal wounds having been inflicted. Everytime I watch a movie and one shot takes out a bad guy, I just shudder at the absolute absurdity of that happening in real life.
If you, say mountain bike, the first thing you do when you crash is check yourself for injuries. Because once you crash, adrenaline floods your system and dulls all of your senses. And you're perfectly capable of getting up and continuing riding with broken ribs and bones and not noticing until the adrenaline is removed from your system.