The impact of DNA evidence in a child sexual assault trial.

Two experiments investigated the impact of DNA evidence in a child sexual assault (CSA) case involving a 6-year-old alleged victim. In Experiment 1, participants read criminal trial summaries of CSA cases in which only DNA evidence was presented, only the alleged child victim's testimony was presented, or both forms of evidence were presented. When DNA evidence was presented, there were more guilty verdicts and greater belief of the alleged victim than when only the alleged victim testified. In Experiment 2, DNA evidence was countered by an alibi witness testifying as to the defendant's whereabouts at the time of the alleged assault. The alibi witness reduced the influence of DNA evidence compared with when DNA evidence was presented without this witness. These results are discussed in terms of the comparative strengths of DNA evidence versus the testimony of the alleged victim.