New York City police officers stand guard in Times Square earlier this month after a blog affiliated with the so-called Islamic State militants mentioned the area as a target for bombing. Andrew Burton/Getty Images hide caption

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In this image taken from video on Jan. 15, police officers Edward Sarama (from left) and Robert McGuire try to talk to officer Matt Dougherty, who is pretending to be mentally ill, during a training simulation at Montgomery County Emergency Service in Norristown, Pa. Michael Rubinkam/AP hide caption

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This hangout spot in East Baltimore — like the rest of the city's outdoor spaces — now comes with a police-enforced nighttime age limit. Children under 14 must be indoors by 9 p.m. each night, all year long. Kids age 14-16 can stay out a little later, until 10 p.m. on school nights and 11 p.m. on other nights. Courtesy of Brian O'Doherty hide caption

itoggle caption Courtesy of Brian O'Doherty

Police officers and other first responders attend a 2012 autism information training session in Wrentham, Mass. Several cities are working to reduce the risk of miscommunication between police officers and people with autism. Elise Amendola/AP hide caption

itoggle caption Elise Amendola/AP

Eric Garner, an unarmed black man, died on July 17 after being placed in a chokehold by police. His death sparked numerous protests, including a march scheduled for this Saturday. Here, Garner's sister Ellisha Flagg (center) leads demonstrators on a march toward the 120th Precinct on July 22, following a vigil demanding justice for her brother. John Minchillo/AP hide caption

itoggle caption John Minchillo/AP

Officers Ned Bandoske (left) and Ernest Stevens are part of San Antonio's mental health squad — a six-person unit that answers the frequent emergency calls where mental illness may play a role. Jenny Gold/Kaiser Health News hide caption

itoggle caption Jenny Gold/Kaiser Health News

A memorial for Eric Garner rests on the pavement near the site of his death. The poster on the ground quotes Garner; video of the arrest shows him telling police officers he couldn't breathe, shortly before he lost consciousness. John Minchillo/AP hide caption

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Officer Michael Crowder says his roots are too deep to leave Detroit, but he knows younger officers who were lured away by better pay. Dawn Uhl-Zifilippo hide caption

itoggle caption Dawn Uhl-Zifilippo

Outside New York City Hall, a policeman watches a protest against racial disparities in marijuana arrests. The majority of those arrested are black or Latino, even though those groups are not more likely to smoke pot. Andrew Burton/Getty Images hide caption

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