FREDDIE GRAY Baltimore, Maryland; April 12, 2015
Police officers arrest Mr Freddie Gray, 25. He is handcuffed and eventually placed on his stomach in a police van. While in transit, Mr Gray asks for medical help but none is given and the police van is diverted to assist in an unrelated case. Mr Gray is later found to be in cardiac arrest, having suffered serious spinal injuries in the van. He dies on April 19, leading to rioting in Baltimore and protests in other United States cities.
Six officers are later charged over the incident. One trial ends in a hung jury, and two others in acquittal. The fourth trial started on Thursday.
WALTER SCOTT North Charleston, South Carolina; April 4, 2015
A video shows police officer Michael Slager gunning down a fleeing black man, 50-year-old Walter Scott, after a traffic stop. Following an altercation, Slager then draws his gun and fires seven to eight shots in Mr Scott's back as he flees.
Slager was charged with murder in June last year. His trial is due to open on Oct 31.
TAMIR RICE Cleveland, Ohio; Nov 22, 2014
A video emerges of US police officers shooting dead Tamir Rice, a 12-year-old carrying a replica gun, just seconds after confronting him. In December last year, the US authorities announced that the police officers concerned will not be prosecuted.
MICHAEL BROWN Ferguson, Missouri; Aug 9, 2014
A white police officer shoots and kills 18-year-old Michael Brown, unleashing sometimes violent protests. A subsequent decision not to indict officer Darren Wilson prompts riots in Ferguson and raises tensions from New York to Seattle.
In March last year, the US Justice Department publishes a scathing report on the shooting, condemning Ferguson's city hall, police department and municipal court for targeting the city's African-American majority.
ERIC GARNER Staten Island, New York; July 17, 2014
Mr Eric Garner, 43, dies after being held in a police chokehold while he is being arrested for selling cigarettes illegally. In an amateur video, police officers are seen wrestling him to the ground. Mr Garner is heard repeating: "I can't breathe." A coroner declares the death a homicide. But a grand jury opts not to charge the white officer involved.