Some Legal Background About Expert Witnesses

“An intelligent evaluation of facts is often difficult or impossible without the application of some scientific, technical, or other specialized knowledge. The most common source of this knowledge is the expert witness ….” [FRE 702- Committee Notes] In non-scientific, financial issues cases, experience often is the predominant, if not sole, basis for reliable expert testimony.

The specialized knowledge-based testimony by the expert often includes the accepted industry standards and principles applicable to the events or transactions at issue in the case. The expert may also take the additional step to infer or conclude whether those standards or principles were met, if the court finds that testimony would be helpful to a determination by the judge or jury. 

To admit experts’ testimony, courts typically find whether experts are qualified based on their knowledge, skill, experience, training, or education, and whether the testimony will be reliable and helpful to the court. Where the testimony is grounded in the experts’ experience in the field, the witness must explain how that experience leads to the conclusion reached, why that experience is a sufficient and reliable basis for the opinion, and how that experience is reliably applied to the facts. See Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311, 1319 (9th Cir. 1995).