The members, some of whom belong to the police department, also play a kind of vigilante role against drug dealers, etc. The group was formed in the 1940s as the Citizens Brigade to defend Twin Peaks prior to the United States' entry into World War II. Among the founders was Sheriff Frederick Truman, whose sons Frank and Harry would succeed him as sheriff and become members of the Bookhouse Boys. They are not afraid to take the law into their own hands: e.g., when Bernard Renault is interrogated in the Bookhouse.