Already one of the longest-serving attorneys general in history, Eric Holder says he has no immediate plans or timetable to leave. Here, he speaks at the annual Attorneys General Winter Meeting in Washington on Feb. 25. Manuel Balce Ceneta/AP hide caption

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Debo Adegbile, special counsel of the NAACP Legal Defense Fund, speaks with the media outside the Supreme Court in Feb. 2013 after presenting arguments in the Shelby County, Ala., v. Holder voting rights case. Evan Vucci/AP hide caption

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The U.S. holds more prisoners in solitary confinement than any other democratic country, according to critics of the treatment. Here, an immigrant detainee makes a call from his "segregation cell" at a detention facility in Adelanto, Calif., last November. John Moore/Getty Images hide caption

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