A comparison of eyewitness and physical evidence on mock-juror decision making

Two studies compared the effectiveness of eyewitness testimony and physical evidence on mock-juror decision making. Jury-eligible participants were ra ndomly assigned to read one of eight versions of a hypothetical murder scen ario and were each asked to render a verdict, to recommend a sentencing opt ion, and to make other evaluative judgments of the defendant. In Study 1, e ither eyewitness testimony or physical evidence was presented, whereas in S tudy 2, both types of evidence were presented together. Also, in both studi es, the strength of evidence varied. Log linear analysis confirmed that moc k jurors' verdicts and evaluative judgments were influenced to a greater ex tent by physical evidence than by eyewitness testimony. Strong evidence pro duced more guilty verdicts than weak evidence, However, combining strong ev idence of both types was no more effective than presenting strong evidence of either type. Implications of these factors for prosecutors and defense a ttorneys in criminal proceedings are discussed.