John Hinckley Jr. is escorted by police in Washington, D.C., on March 30, 1981, following his arrest after shooting and seriously wounding then-President Ronald Reagan. AFP/Getty Images hide caption

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Students sit at the Virginia Tech campus on April 18, 2007, two days after a student killed 32 people and himself. FBI victim specialists span out to help in the wake of crimes like the Virginia Tech massacre. Mary Altaffer/AP hide caption

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Carolyn Lerner is the new head of the U.S. Office of Special Counsel. Peter Krogh/Courtesy of U.S. Office of Special Counsel hide caption

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Patricia Maisch, one of the people who helped halt the Tucson shooting that killed six and wounded 13, including Arizona Rep. Gabrielle Giffords, holds up a photograph of victim John Roll, a federal judge, while testifying before a Senate subcommittee on Tuesday. Maisch testified in support of legislation that would strengthen federal power over the states' handling of background checks. Chip Somodevilla/Getty Images hide caption

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U.S. authorities must now decide the fate of Ali Mussa Daqduq — shown here on a poster at a 2007 U.S. military news conference in Baghdad — and other enemy combatants once troops withdraw from Iraq. Chris Hondros/AFP/Getty Images hide caption

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A placard featuring the photo of a child sits on a table during a conference on human sex trafficking last month in Atlanta. In Fairfax County, Va., gang members who have forced girls as young as 12 into prostitution are being sent to prison. Prosecutors there expect to bring more sex trafficking cases against gang members over the next several months. David Goldman/AP hide caption

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U.S. Attorney General Eric Holder is sworn in before testifying during a Senate Judiciary Committee hearing about the controversial "Fast and Furious" gun-trafficking program on Tuesday. Mark Wilson/Getty Images hide caption

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U.S. Border Patrol vehicles drive from a checkpoint in December 2010, as teams of border officers comb the Arizona desert about 10 miles north of Mexico in search for a suspect in the fatal shooting of U.S. Border Patrol agent Brian Terry in the rugged terrain in Rio Rico, Ariz.

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