nine years after james duckett had been sentenced to death, the key witness in his prosecution, gwen gurleyed at his original trial. but the presiding judge put a stop to gwen's admission, warning her of perjury charges if she changed her testimony. >> judge lockett told me if i perjured myself that i could be sentenced to the maximum of i think it was seven years for each perjury. so i pled the fifth. >> we asked the judge to grant immunity and he just didn't do it. >> how can you kill somebody, how can you execute somebody and you have a state's key witness that wants to tell the truth and yet because it is not what the state wants, they're going to threaten her with perjury and send her back to prison. what kind of system is that? >> while duckett's appeal was severely weakened without gurley's recanted testimony, beth wells was still able to attack the prosecution's case starting with the tire tracks found near teresa's body. >> that little dirt road still had the tire tracks on it. which was a pretty good catch by the detective. so they did the right thing and preserved the tracks. the