You are confusing civil and criminal cases. A bar owner CAN be found negligent and responsible if he over-serves a patron and that patron goes out and injures another person or property. However, 1) it is not entirely clear that an employer could be held to the same standard as a bar owner in that situation and found responsible for injuries caused after a holiday party, and 2) you are on your own for the DUI. The liability (if any) for proximately caused damages of the person who serves the drinks does not extend to the criminal charges against the drinker.
