Ferguson activists march through downtown St. Louis during a protest last month. Scott Olson/Getty Images hide caption

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Martin Luther King Jr., with his wife, Coretta, at a Harlem hospital after he was stabbed by Izola Ware Curry in 1958. AP hide caption

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Rev. Willie Barrow, a 'superdelegate,' attending the opening night of the 2008 Democratic National Convention. The long-time activist, who was a mentor to President Obama, died on Thursday. Melanie Stetson Freeman/Christian Science Monitor/Getty hide caption

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Spider Martin's most well-known photograph, Two Minute Warning, shows marchers facing a line of state troopers in Selma moments before police beat the protestors on March 7, 1965. The day became known as Bloody Sunday. Spider Martin/Courtesy Tracy Martin hide caption

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Tonya DeBerry (center) and her children, Herbert Nelson and Allison Nelson, have all been held in Ferguson and Jennings jails for unpaid traffic tickets. Joseph Shapiro/NPR hide caption

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Rosa Parks, shown in Seattle in 1956, saved postcards from Martin Luther King Jr. and notes about carpooling during the Montgomery Bus Boycott. They're now being cataloged by the Library of Congress. Gil Baker/Courtesy of the Library of Congress, Rosa & Raymond Parks Institute for Self Development hide caption

itoggle caption Gil Baker/Courtesy of the Library of Congress, Rosa & Raymond Parks Institute for Self Development

Amy Barnes, of Marietta, Ga., has won a settlement after she says police abused her constitutional rights. Barnes was arrested and held in solitary confinement overnight for cursing at officers. David Goldman/AP hide caption

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Bryan Stevenson takes on cases to exonerate people wrongfully convicted. "One of the things that pains me is we have so tragically underestimated the trauma, the hardship we create in this country when we treat people unfairly, when we incarcerate them unfairly, when we condemn them unfairly," he says. Tracy King/iStockphoto hide caption

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A memorial sits at the site of Michael Brown's death in Ferguson, Mo. Any investigation into his shooting by a police officer is likely to take months. Larry W. Smith/EPA/Landov hide caption

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(From left) Joseph McNeil and Franklin McCain, two of the Greensboro Four who the day before had sat at the "whites only" counter of a Woolworth store, came back on Feb. 2, 1960, with two others — Billy Smith and Clarence Henderson. Jack Moebes/Greensboro News & Record hide caption

itoggle caption Jack Moebes/Greensboro News & Record

President Obama reached out to touch the statue of civil rights icon Rosa Parks during Wednesday's dedication ceremony in the U.S. Capitol. Senate Minority Leader Mitch McConnell, R-Ky., was behind the president. Jason Reed/Reuters /Landov hide caption

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Robert Carter (second from left) and other attorneys with the NAACP Legal Defense and Educational Fund in 1954. Others (from left to right): Louis L. Redding, Oliver W. Hill, Thurgood Marshall and Spottswood W. Robinson III. AP hide caption

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