The worst part about that fact is that that's better accuracy than the average for cops. For the US army, it's about 50% accuracy under duress, and cops are about 30%.
I'm not sure about the exact laws where the incident occurred, but in several other states that I know the law of, aggravated assault carries the exact same penalties as attempted murder. Because of the wording of the two laws, aggravated assault is much easier to prove. If you're a prosecutor, why would you not go with the easier to prove, exact same penalty crime?
I have to be honest, I was surprised the delivery driver wasn't black. This idiot was just ready to kill someone, anyone. He's probably been looking out his front window, gun in hand, at every little noise for months or years.
And even if the kid was trying to steal an empty car, this guy would still go to prison if he killed him because no one's life or health was in danger. Stealing a car is not a capital offense.