Strange story, why would the police check him during the preflight check? I mean this guy not just had some left over alcohol, this guy was stone drunk with a BAC of 0.96. Why did this guy even show up for work, what about his fellow crew members, why did they not tell him to book off before the flight?
Now about the car laws. In the US you can sleep in the car drunk as long as the key is not in the ignition. Charging a guy because he is asleep in the back seat is ridiculous.