When I lived in Seattle, there was a California attorney being interviewed on local talk radio about California (not washington, but interesting) law regarding using deadly force. Here is the example he used to drive the point home:
If you are a woman who has just been the victim of a home invasion and the perp has just brutally raped you and left you for dead, as you lay on your living room floor he is exiting your apartment. You suddenly notice your hand is touching your pistol under your sofa. In a fit of adrenylin, you grab the pistol, force yourself up, aim the pistol and shoot him in the doorway. He dies of his wounds.
You are guilty of first degree manslaughter (at the least) because the guy was leaving and not a current threat to your life.
I no longer take the law seriously in this country.
I volunteer to serve on this jury...in fact, I don’t do much more than send in an absentee ballot: NOT GUILTY.
If you're smart, you are only guilty of perjury, and it's not provable in court.
The rapist turned back, said he was going to shoot/stab/beat you to death, took a step toward you, and only then, when your life was in immediate danger, did you decide to shoot. In the moment it took your shaky hand to squeeze the trigger, he turned away, so the bullet hit him in the back, but at the time you started to pull the trigger, your life was in immediate danger.
(1) Don't give any details, truthful or not, without a lawyer, and
(2) don't recant or waver once you have decided how and why your life was in immediate danger when you shot that predator in the back.