Jennifer E. Alleyne, Kaustubh G. Joshi and Marie E. Gehle
Journal of the American Academy of Psychiatry and the Law Online June 2016, 44 (2) 265-267
Here is the Discussion Section:
Sexually dangerous individual (or sexually violent predator) laws across the country follow a general scheme. The individual has been convicted of certain sexual offenses and has a mental abnormality or personality disorder that makes him likely to commit similar crimes in the future. Whether decided by a judge or jury, the result is frequently the indefinite commitment of the person. Because the questions at hand are generally outside the expertise of the trier of fact, the testimony of qualified expert witnesses is crucial. Therefore, the admissibility and credibility of mental health testimony are often heavily scrutinized during the proceedings.
Mr. Loy sought to find Dr. Sullivan's and Dr. Volk's testimonies inadmissible on different grounds. Having a license on probation, giving testimony that creates an alleged bias, or, for example, routinely testifying for one side versus the other does not automatically render the witness unqualified or the testimony inadmissible. In most jurisdictions, the case law and statutes governing the admission of expert witness testimony allow for its use if the witness has some degree of expertise in the field in which he will testify and if the testimony helps the trier of fact to understand the evidence or determine a fact at issue.
Inherent in the civil commitment of sexual offenders are complex concerns regarding psychiatric diagnoses, risk assessment, and volitional impairment. The trier of fact depends on expert testimony to understand and decide these questions. If the expert has a skeleton in the closet, has an imperfection in his qualifications, or holds an alleged bias, the trier of fact should appropriately weigh the credibility of that testimony when rendering a decision. Such testimony is not automatically inadmissible. A court's discretion in admitting expert witness testimony will not be reversed unless the district court abuses its discretion in admitting expert testimony. Finally, in most jurisdictions, the court's assessment of witness credibility is granted deference.
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