I get the leathal force part. The car senario was ment to draw your focus to the fact that driving irrisponceably and acting irrisponably are the same thing. ramming your car into someone else's because you wanted to get around someone else driving too slow for your personal preferance is and killing them is usually manslauter. That is no different that bashing a bat into someone's face after they deliberatly antaginize you.
Don't get me wrong- the kid is at fault. He is definanly old enough to know that is not acceptable behavior, even if his parents don't teach it, or act that way, at home. I was just thinking that charging a 13 year-old kid with murder, then letting a supposed adult off with mere manslauter for very similar crimes is wrong.