Police riot

A police riot is a riot carried out by the police; a riot that the police are responsible for instigating, escalating or sustaining as a violent confrontation; an event characterized by widespread police brutality; a mass police action that is violently undertaken against civilians for the purpose of political repression. The term "police riot" was popularized after its use in the Walker Report, which investigated the events surrounding the 1968 Democratic National Convention in Chicago to describe the "unrestrained and indiscriminate" violence that the police "inflicted upon persons who had broken no law, disobeyed no order, made no threat." In this sense a police riot refers to rioting carried out by the police (or those acting in a police capacity) rather than a riot carried out by people who may be motivated to a greater or lesser degree by grievances with the police (see the 1981 Toxteth riots or the 1992 Los Angeles Riots for examples of riots over policing rather than police riots).

During the early years of labor union organizing, police violence was frequently used in efforts to quell protesting workers. One notable incident took place in May 1886, when police killed four striking workers at the McCormick Harvesting Machine Co. in Chicago. The following day, a peaceful demonstration in Haymarket Square erupted in violence when a bomb was thrown, killing eight policemen. Other police then opened fire, before or after they were fired on by people in the crowd (accounts vary) killing at least four demonstrators and wounding an undetermined number, in an event known as the Haymarket Riot.

In July 1934, police in San Francisco were involved in several encounters with striking longshore workers. After two picketers were killed, the other area unions joined together and called a general strike of all workers (the "Big Strike"). Subsequent criticism of the police was probably the occasion for the coining of the term "police riot."

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