It was based on a novel by Ward Greene called Death in the Deep  South, which was in turn a fictionalized account of a real-life case: the trial and subsequent lynching of Leo Frank after the murder of Mary Phagan in 1913.
This story stemmed from Ward Greene’s novel "Death in the Deep South," which portrayed a true-life case: the trial and lynchings of Leo Frank after he was accused of killing Mary Phagan in 1913.