Drunk while asleep in a car? Could be a problem if the engine was running actually. Probably to keep warm I guess, but if the engine is running and the car is not on his own private property, he could have a problem.
There was an Everybody Loves Raymond about this. Debra was too tipsy to drive, but didn’t want Ray’s parents to see her dropped off by a cab, so she slept in her car. She was arrested and had to go to a hearing to determine if her license would be revoked. Her defense was “intent to nap.”