In this Nov. 24, 2015, file photo, Chicago police officers line up outside the District 1 central headquarters in Chicago, during a protest for the fatal police shooting of 17-year-old Laquan McDonald.
An elderly man lights a candle during a rally against the murder of Brazilian councilwoman and activist Marielle Franco, in Sao Paulo Brazil on March 15, 2018. Brazilians mourned for the Rio de Janeiro councilwoman and outspoken critic of police brutality who was shot in the city center in an assassination-style killing.
Miguel Schincariol /AFP/Getty Images
On Dec. 21, 2017, Trina Singleton holds a photo of her eldest son Darryl who was murdered in 2016. The Philadelphia Obituary Project, a new website, is working to show that homicide victims in Philadelphia are more than statistics.
Members of the San Leandro Police Department SWAT Team during a planned training exercise in 2013. The FBI has been monitoring "swatting" — made-up crimes called in to 911 that are designed to get SWAT teams to deploy — for nearly 10 years.
The mass shooting in Las Vegas this month was one of the latest incidents to draw listeners to apps allowing the public to listen to police and fire frequencies.
Mark Ralston/AFP/Getty Images
A police officer in Redford Township, Mich., leads Michael Zaydel to jail after he turned himself in, delivering doughnuts and a bagel while he was at it.
Redford Township Police Department
Fifty-eight white crosses for the victims of the shooting on the Las Vegas Strip earlier this month are arrayed Oct. 6 just south of the Mandalay Bay hotel. The shooter fired down on a crowd of concertgoers from a room in the hotel, and on Thursday its parent company disputed the police timeline of the attack.
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This is a Nov. 17, 1967 file photo of former president Lyndon B. Johnson. That year a commission Johnson had organized to come up with recommendations for how to win his "war on crime" issued their report. The legacy of some of those recommendations can be seen today.
Nurse Alex Wubbels (right) displays video frame grabs of herself being taken into custody while her attorney, Karra Porter, looks on during an interview Friday. Wubbels was arrested after she told a police detective it was against hospital policy to conduct a blood draw from an unconscious patient without a warrant.