You never shoot to kill, you shoot to neutralize the threat. Minimum response is typically two shots to center mass. Then you make sure the world is a safe place and reassess the threat.
“You never shoot to kill, you shoot to neutralize the threat.”
...and offer the responding LEO no more explanation than “I was in fear of my life”. And never waver in that story. Bottom line, whose family do you want grieving, your’s or the perp’s?