Serbian police officers of the Special Anti-Terrorist Unit pose for a picture in their base outside Belgrade October 8, 2014. When the killing of an unarmed black teenager by a white policeman in Ferguson, Missouri, in August sparked sometimes violent protests, the response of police in camouflage gear and armoured vehicles wielding stun grenades and assault rifles seemed more like a combat operation than a public order measure. Some U.S. police departments have recently acquired U.S. military-surplus hardware from wars abroad, but there are many law enforcers around the world whose rules of engagement also allow the use of lethal force with relatively few restrictions. But for every regulation that gives police wide scope to use firearms, there is another code that sharply limits their use. In Serbia, police may use measures ranging from batons to special vehicles, water cannon and tear gas on groups of people who have gathered illegally and are behaving in a way that is violent or could cause violence, but they may use firearms only when life is endangered. (Photo by Marko Djurica/Reuters)

A witch doctor prepares an offering for the inauguration of the World People's Conference on Climate Change and the Defense of Life, prior to the World Climate Change Conference, in Tiquipaya, Bolivia, October 10, 2015. Almost 150 nations, including major emitters led by China and the United States, have submitted plans to the United Nations for curbing greenhouse gas emissions blamed by the U.N. for causing more floods, droughts and heat waves. France will host the conference in Le Bourget, near Paris, from November 30 to December 11, 2015. (Photo by David Mercado/Reuters)

Models wait backstage during the Ukrainian Fashion Week in Kiev, October 16, 2015. (Photo by Valentyn Ogirenko/Reuters)

Men walk towards law enforcement with their hands up on August 24, 2020 in Kenosha, Wisconsin. A second night of civil unrest occurred after the shooting of Jacob Blake, 29, on August 23. Blake was shot multiple times in the back by Wisconsin police officers after attempting to enter into the drivers side of a vehicle. (Photo by Brandon Bell/Getty Images)

Pals let their hair down for one last hoorah in Cardiff, capital of Wales on September 12, 2020. Groups of friends crammed into pubs and restaurants to “go out in style” before the “rule of six” is enforced on Monday. (Photo by Huw Evans Picture Agency/The Sun)

A handout TV grab made available by the Demiroren News Agency (DHA) on September 12, 2020, shows a freak sandstorm sweeping over Polatli, in Ankara, on September 12, 2020. A freak sandstorm hit Ankara on September 12, 2020, the Turkish capital's mayor said, as officials said six people were injured after strong winds. (Photo by Handout/DHA via AFP Photo)

Bystanders look at MV Wakashio bulk carrier that had run aground and from which oil is leaking near Blue Bay Marine Park in south-east Mauritius on August 6, 2020. The carrier, belonging to a Japanese company but Panamanian-flagged, ran aground on July 25 and its crew was evacuated safely. The ship was empty at the time but was carrying 200 tonnes of diesel and 3,800 tonnes of bunker fuel, according to the local press. (Photo by Dev Ramkhelawon/L'Express Maurice/AFP Photo)

A stag reacts as magpies and crows fuss over a resting stag as they feed on ticks from the fur of the deer herd roaming on the Ashton Court Estate, Bristol, in crisp and cold Autumnal weather on November 23, 2020. (Photo by Ben Birchall/PA Images via Getty Images)