Assuming there is not more to the story, I wish gun owners would use better discretion. Shooting thru doors or out your window is hardly “self-defense.” Everytime some knucklehead kills some innocent person like this, it hurts the Second Amendment and our cause. Ugh.
The best argument for trigger discipline is that you won’t be pulling the trigger just because you might be experiencing heightened adrenaline levels. That’s also why it’s a bad idea to rest your trigger finger on the mag release button of your AR. Don’t need to hit that in the excitement, either.