Riot control refers to the measures used by police , military , or other security forces to control , disperse , and arrest people who are involved in a riot , demonstration , or protest . If a riot is spontaneous and irrational , actions which cause people to stop and think for a moment ( e.g. loud noises or issuing instructions in a calm tone ) can be enough to stop it . However , these methods usually fail when there is severe anger with a legitimate cause , or the riot was planned or organized . Law enforcement officers or military personnel have long used less lethal weapons such as batons and whips to disperse crowds and detain rioters . Since the 1980s , riot control officers have also used tear gas , pepper spray , rubber bullets , and electric tasers . In some cases , riot squads may also use Long Range Acoustic Devices , water cannons , armoured fighting vehicles , aerial surveillance , police dogs or mounted police on horses . Officers performing riot control typically wear protective equipment such as riot helmets , face visors , body armor ( vests , neck protectors , knee pads , etc. ) , gas masks and riot shields . However , there are also cases where lethal weapons are used to violently suppress a protest or riot , as in the Boston Massacre , Haymarket Massacre , Banana Massacre , Hungarian Revolution of 1956 , Kent State Massacre , Soweto Uprising , Mendiola Massacre , Bloody Sunday ( 1905 ) , Ponce massacre , Bloody Sunday ( 1972 ) , Venezuelan Protest ( 2017 ) , Tuticorin Massacre ( 2018 )
Bloody Sunday ( 1972 )
Bloody Sunday (1972)
Riot control