Wow, sorry to hear about the injuries, but glad to hear it wasn't worse.

Just curious, how old is your truck? It sounds like there may be something wrong with it unless it is pretty old. They started putting the ignition/shifter interlock on them back in the early 70's didn't they? He shouldn't have been able to shift it out of park without a key - unless it is old enough to have been built before the interlock became standard anti-theft equipment....