Anti-social behavior such as flaming and griefing is pervasive and problematic in many online venues. This behavior breaks established norms and unsettles the well-being and development of online communities. In a popular online game, Riot Games's League of Legends, the game company received tens of thousands of complaints about others every day. To regulate what they call "toxic" behavior, Riot devised the "Tribunal" system as a way of letting the community to police itself. The Tribunal is a crowdsoucing system that empowers players to identify and judge misbehavior.