A riot is a form of civil disorder commonly characterized by a group lashing out in a violent public disturbance against authority, property or people. Riots typically involve vandalism and the destruction of property, public or private. The property targeted varies depending on the riot and the inclinations of those involved. Targets can include shops, cars, restaurants, state-owned institutions, and religious buildings. Riots often occur in reaction to a perceived grievance or out of dissent. Historically, riots have occurred due to poor working or living conditions, governmental oppression, taxation or conscription, conflicts between ethnic groups, or religions, the outcome of a sporting event or frustration with legal channels through which to air grievances. While individuals may attempt to lead or control a riot, riots typically consist of disorganized groups that are frequently "chaotic and exhibit herd behavior." However, there is a growing body of evidence to suggest that riots are not irrational, herd-like behavior, but actually follow inverted social norms. T. S.