From Elliot Ness to Robert Kennedy, America has a long history of crusaders against organized crime, but one name is far less known. Back in the 1930s, Eunice Carter, a granddaughter of slaves, became New York’s first African-American assistant district attorney. She's credited with helping take down one of America’s most notorious mob bosses, known as "Lucky Luciano." It's just one of the fascinating stories told in a new biography of Carter, "Invisible," written by her grandson, Yale law professor Stephen Carter. Michelle Miller reports.