Do Vigilante Groups Reduce Cartel-Related Violence? An Empirical Assessment of Crime Trends in Michoacán, Mexico

Abstract When the Knights Templar cartel targeted the people of Michoacán, vigilantes formed for protection. This study uses a paired sample t-test to investigate the effect that the emergence and subsequent removal of the vigilantes and their confrontational approach against the Knights Templar had on cartel-related crimes. Initially, homicides increased in vigilante areas, while kidnappings and extortions decreased. After vigilantes were removed, homicides and kidnappings increased, while extortions decreased. Government removal of vigilantes allowed for a power vacuum to ensue, allowing violence to increase. Therefore, violence initially increases with vigilante presence, then decreases, while increasing again once the group is removed.