The testimony of experts in child sex abuse trials is controversial. There are serious legal constraints on expert testimony concerning credibility of the witness, properly the domain of the trier of fact (see US vs. Brooks, a court martial, where my testimony was rejected by a military court of appeals as crossing the line). Thus, case specific testimony is strictly proscribed. The question is whether “social framework evidence” testimony is helpful and ought to be admitted: “Experts educate fact-finders about general scientific findings, regarding the reliability of children’s reports so they can use the information in weighing the evidence.” There is some literature on what sort of testimony is most effective. I found one reference that stated that combined case specific and general educational testimony were together most effective; general education testimony least effective.
Do juries need such information? Is the information about forensic interviews of children, issues related to memory and suggestibility, and issues related to the quality of forensic interviews provided by the expert “outside the jury’s ken”? Is it helpful? Buck, London, and Wright’s piece in Law Human Behavior will be very helpful to counsel and expert witnesses on either side in assessing testimony strategy and tactics.
Reference: Buck, JA., London, K., & Wright, DB (2011). Expert testimony regarding child witnesses: Does it sensitize jurors to forensic interview quality? Law and Human Behavior, 35: 152-164.