Robert Bates (left), a Tulsa County, Okla., reserve deputy, leaves his arraignment Tuesday with his attorney. Bates fatally shot a suspect who was pinned down by officers, raising alarms about volunteer police officers who wear badges and carry guns. Sue Ogrocki/AP hide caption

itoggle caption Sue Ogrocki/AP

Makeshift memorials to Walter Scott sprouted up at the scene of his fatal encounter with Michael Slager, the police officer who shot him in the back as he ran away following a routine traffic stop. David Goldman/AP hide caption

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Multiple lawsuits accuse the New York City Police Department of pressuring officers into fulfilling monthly quotes for tickets and arrests, resulting in warrantless stops. The NYPD denies the allegations. Spencer Platt/Getty hide caption

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Detective Mark Williams (right) speaks with an officer in Richmond, Va. A decade ago, amid a surge in violent crime, Richmond police were identifying relatively few murder suspects. So the police department refocused its efforts to bring up its "clearance rate." Alex Matzke for NPR hide caption

itoggle caption Alex Matzke for NPR

Indiana "Indy" Bones reports for duty on a field investigation, in which the dog sniffs to detect human remains for a reopened cold case. Gloria Hillard/NPR hide caption

itoggle caption Gloria Hillard/NPR

Body cameras, like this one shown at a 2014 press conference in Washington, D.C., are small enough to be clipped to an officer's chest. Washington and Denver are among U.S. cities trying the cameras. BRENDAN SMIALOWSKI/AFP/Getty Images hide caption

itoggle caption BRENDAN SMIALOWSKI/AFP/Getty Images

The 2,100-person Tijuana municipal police force is one of Mexico's largest. It's also the first in the country to employ body cameras for its officers. Washington Post/Getty Images hide caption

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Madison Mayor Paul Soglin addresses a crowd of protesters on Martin Luther King Boulevard in Madison, Wis., during a protest of the shooting death of Tony Robinson. Andy Manis/AP hide caption

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Ferguson, Mo., Police Chief Thomas Jackson is resigning after a scathing Justice Department report showed racial bias in the department and the city's courts. Jeff Roberson/AP hide caption

itoggle caption Jeff Roberson/AP

A cellphone video captured the deadly struggle between Los Angeles police officers and a man on a city sidewalk (in background). Seconds after this image appears in the video, shots were fired that killed the man, a robbery suspect. Anthony Blackburn/Facebook hide caption

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