Your lead should set the stage for your proof that Juror Eight is a hero.  Present the situation in which Juror Eight finds himself, including the circumstances that cause him to initially vote as he did.  By explaining the testimony presented before the jurors begin their deliberations, you build your basis to support your later conclusions.  Summarize the positions initially taken by the other members of the jury and the reasons for those positions, as the contrast and conflict resulting from the differing opinions is the critical focus of the story.