Attorney General Eric Holder speaks before a meeting of the National Association of Attorneys General on Tuesday. Manuel Balce Ceneta/AP hide caption

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Caitlin J. Halligan, shown in 2005, waited more than 700 days in the last Congress for a vote on the Senate floor before she was filibustered, the White House says. She was nominated again last month. Jim McKnight/AP hide caption

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In this 1971 file photo, the real-life Frank Serpico (center, with beard) appears at a hearing during an investigation into police corruption in New York City. Jim Wells/AP hide caption

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President Obama "strongly but respectfully disagrees with the ruling" on recess appointments by a federal appeals court, says White House spokesman Jay Carney. Carolyn Kaster/AP hide caption

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New White House Chief of Staff Denis McDonough (left), at Friday's announcement. Behind the president: outgoing Chief of Staff Jacob "Jack" Lew, who has been nominated to be Treasury secretary. Jewel Samad /AFP/Getty Images hide caption

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Sen. Dianne Feinstein, D-Calif., speaks at a news conference Thursday announcing her plan to introduce a bill to ban assault weapons and high-capacity magazines. Alex Wong/Getty Images hide caption

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Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., voted to allow guns in national parks and on Amtrak trains, but rejects suggestions that he'll slow-walk gun control efforts through Congress. Chip Somodevilla/Getty Images hide caption

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Handgun barrels on the assembly line of Hi-Point Firearms in Mansfield, Ohio. Gus Chan/The Plain Dealer /Landov hide caption

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The Transocean Discoverer Enterprise drill ship collects oil from the site of the Deepwater Horizon oil well as workers try to stem the flow of the spill in the Gulf of Mexico, June 12, 2010. Saul Loeb/AFP/Getty Images hide caption

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