ISSN : 2093-3843
The current study aimed to test the impact of unique evidence, on which the prosecution was solely based, upon the lay people’s verdict for the defendant. We also examined if the probability of the defendant’s guilt and the probative value of evidence would vary by the type of the sole evidence and the existence of additional evidence. In the study, 250 lay people participated and were asked to read one of the four simple trial scenarios, to render a verdict for the defendant, and to estimate the probative value of evidence and probability of the defendant’s guilt. The results showed that lay people tended to return a guilty verdict. The additional evidence was found to play a significant role in estimation of the probability of the defendant’s guilt and of the probative value of the evidence, depending on the type of the additional evidence. In discussion, it was suggested that lay people would overestimate the probative value of the unique evidence that was the sole basis of the prosecution. Finally, we discussed the influence of the evidence type on legal judgement in trials.
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