The Trial Court\u27s Gatekeeper Role under Frye, Daubert, and Kumho: A Special Look at Children\u27s Cases

The typical requisites for receiving testimony from an expert witness are that the expert be qualified in a particular subject or area of expertise, that the expert testify in opinion form or otherwise, which will help the fact finder, and that there be a proper basis for the expert\u27s testimony. This article examines the changing meaning in the law of evidence of the expert\u27s subject area in cases involving children. During most of the last century, where the expert witness proposed to testify concerning a new or novel scientific system, process or technique, the court applied the rule of Frye v. U.S. to determine the reliability of the subject matter. The Frye test requires the court to determine whether the new scientific process is generally accepted in the scientific community to which it belongs. In other cases involving experts, the courts have been left to determine, in the exercise of discretion, whether they feel comfortable putting a particular subject in front of the jury or admitting the evidence in a bench case. Since most experts do not testify about evidence derived from a novel scientific system or technique, the courts in most cases have applied the traditional rules, which apply to expert witness testimony. As a rule, most of the new or novel scientific evidence was derived from the physical or hard sciences. In Daubert v. Merrell Dow Pharmaceuticals, the U.S. Supreme Court held that the Federal Rules of Evidence and not Frye determine the admissibility of scientific evidence in the federal district courts. Under Daubert, the court must make a preliminary assessment of whether the reasons (principles) or methods (techniques) are scientifically valid (reliable) and can be properly applied to the facts of the case. Daubert provided a list of preliminary considerations for the trial court judge to use in deciding whether to admit the evidence. The Supreme Court clarified its Daubert decision in Kumho Tire Co. v. Carmichael, by extending the Daubert analytical framework and list of factors beyond scientific knowledge to cases involving technical or other specialized knowledge. Thus, Kumho directs the federal district court to consider the Daubert factors, and others as necessary, with every expert witness. While the federal law is developing along the lines of Daubert and Kumho, the states are taking various approaches to expert testimony. Some jurisdictions continue to adhere to the Frye rule, others have embraced Daubert but not Kumho, some states have adopted both Daubert and Kumho, and other state jurisdictions have developed their own tests with respect to scientific, technical, or other specialized knowledge described by experts. This article analyzes these various approaches, with special emphasis upon the proliferation of non-traditional, soft psychological evidence, which frequently is at the center of cases involving children