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 Russian peacekeeper shouts “No pictures!” at a checkpoint outside the city of Stepanakert on November 13, 2020, during a ceasefire in the military conflict between Armenia and Azerbaijan over the breakaway region of Nagorno-Karabakh. Russian began deploying 2,000 peacekeepers to Nagorno-Karabakh on November 10 after Armenia and Azerbaijan agreed a peace deal to end weeks of fierce fighting over the disputed region. (Photo by Alexander Nemenov/AFP Photo)

Katie Austin (L) and Denise Austin attend the 2019 ESPY Awards at Microsoft Theater on July 10, 2019 in Los Angeles, California. (Photo by Chelsea Lauren/Rex Features/Shutterstock)

A graduated cadet bleeds after being hit by a hat tossed in the air, at the end of the 2023 graduation ceremony at the United States Military Academy (USMA), at Michie Stadium in West Point, New York, U.S., May 27, 2023. (Photo by Eduardo Munoz/Reuters)

Frank A. Rinehart, a commercial photographer in Omaha, Nebraska, was commissioned to photograph the 1898 Indian Congress, part of the Trans-Mississippi International Exposition. More than five hundred Native Americans from thirty-five tribes attended the conference, providing the gifted photographer and artist an opportunity to create a stunning visual document of Native American life and culture at the dawn of the 20th century. Photo: Little Bird, Arapahoe, 1899. (Photo by Frank A. Rinehart)

Breitling Wingwalker Freya Paterson, from Liverpool, UK, flies above Kuwait City's iconic Water Towers with pilots David Barrell and Martyn Carrington, on March 6, 2014. The team loop and roll up to 160 mph enduring G-forces of 4-5g. Crowds are expected to line the Kuwaiti coastline to catch a glimpse of the Wingwalking team on Saturday, March 8, 2014, to mark the opening of the first dedicated boutique in the city for the prestigious watch brand. (Photo by Katsuhiko Tokunaga/Breitling)

Mug shot of William Stanley Moore, 1 May 1925, Central Police Station, Sydney. This picture appears in the Photo Supplement to the NSW Police Gazette, 28 July, 1926 captioned: “Opium dealer. Operates with large quantities of faked opium and cocaine. A wharf labourer; associates with water front thieves and drug traders”. (Photo by NSW Police Forensic Photography Archive, Justice & Police Museum, Histiric Houses Trust of NSW)

A member of the Unidos do Viradouro samba school performs during the last night of the Carnival parade at the Marques de Sapucai Sambadrome in Rio de Janeiro, Brazil, on February 13, 2024. (Photo by Pablo Porciuncula/AFP Photo)