A police officer who was injured when falling of a horse during scuffles with demonstrators at Downing Street during a Black Lives Matter march in London, Saturday, June 6, 2020, is dragged by colleagues, as people protest against the killing of George Floyd by police officers in Minneapolis, USA. Floyd, a black man, died after he was restrained by Minneapolis police while in custody on May 25 in Minnesota. (Photo by Frank Augstein/AP Photo)

A demonstrator confronts a police officer outside the 18th District Police station during a rally after the death of Walter Wallace Jr., a Black man who was shot by police in Philadelphia, Pennsylvania, U.S., October 27, 2020. (Photo by Bastiaan Slabbers/Reuters)

A man raises his fist as a group of Black Lives Matter marchers approached Brooklyn's Grand Army Plaza ast the beginning of a Caribbean-led rally, Sunday, June 14, 2020, in New York. Protests have grown since the May 25th death of George Floyd, a black man who died inn police custody in Minneapolis after a white police officer pressed his knee into Floyd's neck for nearly nine minutes. (Photo by Kathy Willens/AP Photo)

Police officers take cover as they clash with protesters after an officer shot and killed a black man in Brooklyn Center, Minneapolis, Minnesota on April 11,2021. Protests broke out April 11, 2021 night after US police fatally shot a young Black man in a suburb of Minneapolis – where a former police officer is currently on trial for the murder of George Floyd. Hundreds of people gathered outside the police station in Brooklyn Center, northwest of Minneapolis. Police fired teargas and flash bangs at the demonstrators, according to an AFP videojournalist at the scene. (Photo by Kerem Yucel/AFP Photo)

New Orleans police officers try to keep their heads down as they move in on a Black Panther headquarters during an exchange of gunfire in New Orleans on September 15, 1970. The shootout occurred as police moved in to make arrests on Tuesday morning following a series of incidents. (Photo by Jack Thornell/AP Photo)

A demonstrator holds up her fist, in front of police officers during a protest, organised by Black Lives Matter Belgium, against racial inequality in the aftermath of the death in Minneapolis police custody of George Floyd, in central Brussels, Belgium on June 7, 2020. (Photo by Yves Herman/Reuters)

A woman stands in front of police officers during a Black Lives Matter protest in London, following the death of George Floyd who died in police custody in Minneapolis, London, Britain, June 7, 2020. (Photo by Dylan Martinez/Reuters)

A man protesting the Ferguson grand jury decision to not indict officer Darren Wilson in the Michael Brown case is arrested while marching through the streets on December 1, 2014 in New York City. Brown, an 18-year-old black man, was killed by Darren Wilson, a white Ferguson, MO police officer, on August 9. (Photo by Andrew Burton/Getty Images)