Omega Research Foundation National Guard official armed with a shotgun. He was reportedly trying to flee at the time he was shot.78 International standards require force to be used exclusively against persons engaged in violence. By their nature metal pellets are indiscriminate and therefore serve no legitimate law enforcement purpose. In a situation where people are acting violently in a public gathering, law enforcement officers should use less harmful means to bring the situation under control.79 An additional advantage of prohibiting rubber pellet ammunition (see above), is that other types of ammunition are more difficult to tamper with. The use of firearms should only be permitted for the purpose of protecting against an imminent threat to life or of serious injury. Any law enforcement officials found to have used firearms in an abusive manner should be held to account and their conduct treated as criminal offences. Recommendations    Law enforcement agencies should be adequately equipped with a range of weapons and ammunition that would allow for a differentiated use of force and firearms. The use of firearms by law enforcement officials should be controlled in accordance with the BPUFF (i.e. to defend against a threat to life or of serious injury), regardless of the type of ammunition being used. Prohibit the use of any firearms or ammunition that cause unnecessary injury or present an unnecessary risk. This includes ammunition which is inherently indiscriminate, including shotgun pellets. Water cannon Water cannon are high-pressure systems designed to fire jets of water at people. They can be backpack style, or more typically mounted on vehicles. The pressure of the water jet can be varied from low pressure (designed to soak, deter or demoralise), to high pressure - which can cause blunt trauma or knock a person to the ground. The water jet can have additives including marker dye (for later identification of persons) or a range of chemical irritants for additional effects. Illustrative country examples of excessive use of force with water cannon Chile: It has been reported that the Chilean Carabineros sometimes respond to violence in public demonstrations with indiscriminate or disproportionate force.80 The Chilean National Human Rights Institute (INDH) reported Carabineros used force indiscriminately and disproportionately in 70% of the demonstrations it observed in 2013, with water cannons used in 77% of these gatherings.81 On 21 May 2015, Rodrigo Avilés sustained serious head injuries after being thrown several metres by a high-pressure jet of water fired by Carabineros from a distance of 4.5 metres.82 78 Ibid. p. 26. For more on this topic, see Amnesty International, Use of Force Report, note 6, pp. 138-139. 80 Human Rights Watch, World Report 2014, p. 224. 81 National Human Rights Institute of Chile, Informe Anual 2013: Programa de Derechos Humanos y Función Policial, May 2014, pp. 25-28. 82 Francisco Marín, ‘Chile: Incentivos perversos para la violencia policiaca,’ Proceso, 12 June 2015, <http://www.proceso.com.mx/?p=407435> [accessed 31 May 2016]. 79 22