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Can Jury Trial Innovations Improve Juror Understanding of DNA Evidence?

NCJ Number
National Institute of Justice Journal Issue: 255 Dated: November 2006 Pages: 2-7
Date Published
November 2006
6 pages
Publication Series
This study examined the influence of four jury-trial innovations on mock jurors' understanding of contested mitochondrial DNA (mtDNA) evidence.
Findings show that jurors who took notes during the trial and were also issued a juror notebook--containing paper, copies of the two experts' slides, the mtDNA checklist, a glossary of DNA terms used in the case, and a witness list--did better on the Jury Comprehension Scales after deliberation than did those allowed only to take notes. The same was true for jurors exposed to all four innovations: note taking, juror questioning, mtDNA checklists, and multipurpose juror notebooks. Researchers recommend five ways to facilitate juror understanding of DNA evidence. First, distribute juror notebooks that contain expert's slides, overheads, and charts; a glossary of technical terms; a list of issues presented by the DNA evidence; and blank paper for note taking. Second, distribute a checklist that contains the issues presented by the DNA evidence and provide a step-by-step pathway for jurors' resolution of the issues. Third, provide a brief explanation of forensic DNA without including technical details about the analysis. Fourth, allay fears of contamination even in cases where there is no evidence it has occurred. Fifth, encourage jurors to weigh the probative value of the DNA evidence that links the defendant to the crime against the value of other nonscientific evidence. The study was conducted with jury-eligible adults called to jury duty in New Castle County, DE. Sixty eight-person juries were divided into groups of 10 juries (n=6 groups). Five groups were given various numbers and combinations of the four innovations, and one group was given no innovations (control group). Groups of jurors were tested for DNA comprehension before and after jury deliberations following the viewing of an armed robbery trial. 5 notes and an mtDNA evidence checklist

Date Published: November 1, 2006