Several recent killings of black men or boys by police officers across the nation and grand juries' decisions not to indict some of the officers have angered many people, especially in minority communities, and have spurred sometimes violent demonstrations.
Here's a look at killings by police that protesters have cited as examples of an epidemic of police brutality and heavy-handed law enforcement efforts often targeting minorities and related events:
On July 17, a white plainclothes police officer, Daniel Pantaleo, applied what a medical examiner determined was a chokehold to an unarmed black man accused of selling loose, untaxed cigarettes on a New York City street. A videotape of the takedown of Eric Garner, who had asthma, showed him repeatedly saying, "I can't breathe," while officers wrestled him to the ground. Garner died soon after, and a grand jury decided Wednesday not to indict Pantaleo, prompting daily protests and chants of "Black lives matter!"
On Aug. 5, a white policeman responding to a call about a man waving what appeared to be a rifle in an Ohio Wal-Mart store shot and killed John Crawford III, who was black. What Crawford was holding was an air rifle. A special grand jury decided in September the actions of Officer Sean Williams and another Beavercreek officer in the racially charged case were justified.
'HANDS UP! DON'T SHOOT!'
On Aug. 9, white police officer Darren Wilson shot and killed unarmed black teenager Michael Brown on a street in Ferguson, Missouri. Supporters of Brown's family say he had his hands up in surrender, but Wilson has said that's "incorrect" and he couldn't have done anything differently in their confrontation. A grand jury decision last month to not indict Wilson sparked violent demonstrations and looting in the St. Louis suburb, and around the nation protesters have chanted, "Hands up! Don't shoot!"
On Nov. 20, a rookie New York Police Department officer walking with his gun drawn in a darkened stairwell of a public housing complex shot and killed a black man leaving the building with his girlfriend. Police Commissioner William Bratton said that Akai Gurley had been "a total innocent" when he was shot and that the shooting, by an Asian officer, was under investigation. The Brooklyn district attorney said Friday that the case would be presented to a grand jury.
PELLET GUN SHOOTING
On Nov. 22, a white rookie police officer, Tim Loehmann, shot and killed a 12-year-old black boy, Tamir Rice, who had been pointing a pellet gun near a Cleveland playground. Police say Tamir was told to raise his hands but reached into his waistband for the realistic-looking airsoft gun, which was missing its orange safety indicator. The shooting, captured on surveillance video, has prompted street protests, and Tamir's family on Friday filed a lawsuit against the city, Loehmann and his partner.
UNARMED DRUG SUSPECT KILLED
On Tuesday, a white police officer who authorities say mistook a pill bottle for a gun shot and killed an unarmed black drug suspect during a struggle at a Phoenix apartment building. About 150 people upset about the killing of Rumain Brisbon marched to police headquarters, and police and prosecutors met with local civil rights leaders.
FIGHT OVER TAILLIGHT TICKET
On Thursday, in tiny Eutawville, South Carolina, a white former police chief was charged with murder in the 2011 shooting death of an unarmed black man, Bernard Bailey, who had gone to Town Hall to argue about a broken-taillight ticket. Bailey and then-chief Richard Combs fought, and Combs shot Bailey twice in the chest. Combs' lawyer accused prosecutors of taking advantage of national outrage toward police to obtain the indictment.
137 BULLETS FIRED
Also Thursday, in Cleveland, the U.S. Department of Justice and the city reached an agreement to overhaul the police department after federal investigators found officers use excessive force far too often, causing deep mistrust, especially among blacks. The investigation was prompted chiefly by a November 2012 car chase that ended in the deaths of two unarmed black people in a hail of 137 bullets.