That is the exact reason why I never served anyone who appeared intoxicated. That is the law actually. If you serve someone who is already drunk, you can be held accountible for the consequences.
When I was working at Denny's a guy walked in and asked for a beer. I told him no. He got pissed and stormed out of the restaurant. He got in his car and proceeded to strike another car head on in the parking lot
Cops came in and asked me about him. They told me if I would have given him anything, I would have been liable as well. Eff that.
while hes at it, why doesnt he sue the car maker for operating under the usage for a drunk driver, the tow truck maker, the tow truck company...the list can go on and on...the gas station for selling the fuel used in the accident...the oil company for providing the oil...the oiler that brought the oil over from the middle east...al queda for operating oil fields, and then the US Government for funding al queda during the cold war