Opinion ID: 1375796
Heading Depth: 3
Heading Rank: 2

Heading: Opinion evidence as an end-run around Frye

Text: The court of appeals suggested that although couched in terms of their personal experience, the experts' testimony effectively conveyed to the jury the then-impermissible random match probability statistics. We do not agree. Both witnesses explained why they had found a match both visually and numerically. They explained that the profiles matched over four probes, though one of the probe matches was rejected in the interests of accuracy and that the areas looked at by RFLP analysis are polymorphic and vary between individuals. This testimony fit within in the scientific evidence category and was permitted because it met the requirements of Frye. The prosecutor then turned to the experts' personal experience, developing their experience with the RFLP analysis and the pertinent literature to support their testimony that they had never personally seen or heard of a random match over three or four loci. However, it was also developed that such a match would be possible between identical twins or even brothers. Defendant chose not to cross-examine the experts on the basis for their opinions, instead focusing on the fact that only a small percentage of DNA differs from person to person, the possibility of laboratory error, bias, and environmental insults to the evidence DNA. As noted, this is the very type of opinion evidence discussed in Roscoe, which is not based on the application of scientific principle but, rather, on the observations and credibility of the witness. Thus, it need only meet the requirements of relevancy and not be substantially more prejudicial than probative. See Ariz.R.Evid. 401 and 403.