i don't mean nothing bad, but my thoughts are more with the family of the person who was killed through no real fault of his own (regardless of the fact he wasn't wearing a seatbelt).
if i had a friend/loved one killed by someone who ran a stop sign, i would move heaven and earth to ensure justice of one kind or another was dealt out.
but the passengers in your friends car are "innocents" too, i hope they recover %100.
if it was a genuine mistake when he ran the stop sign, my heart go's out to him, if it wasn't, then i hope this torments him for the rest of his days.