Former University of Chicago student Clyde Kennard was sentenced to seven years hard labor for stealing a bag of chicken feed in 1960, but he died in 1963 after developing cancer that went untreated while he was in prison.
However, many critics have defended Kennard, stating he was framed for trying to integrate what is now the University of Southern Mississippi.
Two years ago, a Northwestern University professor and a group of high school history students began working to clear his name, the Chicago Tribune reported Friday.
In May 2006, a judge declared Kennard innocent, agreeing he was prosecuted because of his integration efforts.
Almost immediately, Richard Barrett, head of the segregationist Nationalist Movement in Learned, Miss., filed a motion to intervene to "redress an erroneous application of law."
However, the state's top court last week said Barrett, as a private citizen, had no standing to challenge the decision.