Police cordon off the area around a shooting in Chicago Wednesday. The violence broke out down the street from where NPR's David Schaper was conducting an interview about urban renewal efforts. David Schaper /NPR hide caption

itoggle caption David Schaper /NPR

A makeshift memorial sits in front of IV Deli Mart, where part of Friday night's mass shooting took place in the Isla Vista, Calif., community. The parents of Elliot Rodger, accused of killing six people, were reportedly rushing to try to stop their son when they heard about the violence. Chris Carlson/AP hide caption

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Michael Dunn reacts after the verdict is read in Jacksonville, Fla., on Saturday. Dunn was convicted of attempted murder in the shooting death of a teenager over an argument over loud music, but jurors could not agree on the most serious charge of first-degree murder. Bob Mack/The Florida Times-Union/AP Pool hide caption

itoggle caption Bob Mack/The Florida Times-Union/AP Pool

A police officer walks out of the Electrical Engineering Building on the campus of Purdue University in West Lafayette, Ind., Tuesday. One person was killed in a classroom by a gunman who surrendered to a police officer within minutes of the attack, officials said. Michael Conroy/AP hide caption

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An image from a Connecticut State Police report on the shootings at Sandy Hook Elementary School shows a scene at 36 Yogananda St. in Newtown, Conn., where Adam Lanza killed his mother before driving to the school and killing 26 students and staff last December. AP hide caption

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Theodore P. Wafer, 54, charged with second-degree murder in the shooting death of Renisha McBride, appears at his arraignment in Dearborn Heights, Mich., on Friday. Paul Sancya/AP hide caption

itoggle caption Paul Sancya/AP

Officers on Capitol Hill look at a car following Thursday's shooting, which left Miriam Carey, 34, dead. "We're still very confused as a family why she's not still alive," Carey's sister says. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP

Flags fly at half-staff Tuesday after the deadly shootings at the Navy Yard in Washington, D.C. J. Scott Applewhite/AP hide caption

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Kathy Gaarde, one of the people killed in Monday's shootings at Washington's Navy Yard, in a family photo. Her husband, Douglass, says the picture depicts Gaarde "with her 94-year-old mother who she cared for until she passed away last year." Douglass Gaarde hide caption

itoggle caption Douglass Gaarde

President Obama walks out to deliver remarks on the economy at the White House on Monday. At the beginning of his news conference, Obama commented on the shootings at the Navy Yard. Pablo Martinez Monsivais/AP hide caption

itoggle caption Pablo Martinez Monsivais/AP

A tribute page to Christopher Lane, an Australian college baseball player who was shot and killed in Oklahoma last week, has drawn thousands of responses on Facebook. Facebook hide caption

itoggle caption Facebook