Smith attempted to shoot her again, but his rifle jammed, prompting Kifer to laugh.Yes, I would think he went a bit beyond self-defense, if this is what he said.
Upset, Smith, pulled out a revolver he had on him and shot her "more times than I needed to" in the chest, he said.
Smith dragged Kifer next to Brady as she gasped for her life. He pressed the revolver's barrel under her chin and pulled the trigger in what he described as a "good, clean finishing shot" that was meant to end her suffering.
See #25, and linked article, for more details. He appears to have admitted that after wounding them, he deliberately finished them off.
From self-defense to 2nd degree murder with a pull of the trigger.
This stinks to high heaven, it looks like these two petty criminal teens ran into a psycho killer.