Short Answer 
The server may face negligence liability under tort law if they fail to report illegal drug sales, as it can lead to harm for others. Dram shop laws also hold establishments accountable for allowing illegal activities, while criminal law could impose penalties for not addressing such behavior, emphasizing the need for vigilance and proactive reporting by servers.
Step 1: Understand Tort Law Implications
Tort law addresses civil wrongs that can cause harm to individuals. In this case, if a server notices guests selling drugs and neglects to report it, the server may be deemed negligent. This negligence may result in legal liability if a guest or other individual suffers harm due to this inaction.
Step 2: Recognize Dram Shop Law Responsibilities
Dram shop laws impose liability on establishments that serve alcohol if they knowingly allow illegal activities, such as drug sales, to occur on their premises. If an incident arises from the drug sale, the establishment may face serious consequences. Thus, it is crucial for servers to monitor and report such activities to avoid potential liability.
Step 3: Comprehend Criminal Law Consequences
Failure to address or report the illegal sale of drugs can lead to repercussions under criminal law for the server or establishment. Depending on jurisdiction, there could be severe penalties for not taking action against criminal behavior occurring on the premises. Servers need to be vigilant and proactive in reporting any unlawful activities to protect themselves and their establishment.