Once I attended a math olympiad training camp, and was told a story explaining why we were not allowed to play &quot;Mafia&quot;:<p>The previous year, students had arranged a real-time version of the game, so that, each night, the mafia would vote and eventually someone would go knock on the victim&#x27;s door.  At some point, a maid found a piece of paper in someone&#x27;s dorm, listing a &quot;God&quot;, the names of people who had been &quot;killed&quot;, who was to be killed that night, etc.  The police were called.<p>The matter was eventually cleared up, but from then on, the camp imposed a strict policy of no &quot;Mafia&quot;.  People were free to play equivalent games, as long as the vocabulary of the game was not something that could conceivably lead to a repeat incident.