Psychologists, psychiatrists, and licensed social workers routinely testify as experts in both criminal and civil cases in which the mental condition of an individual is at issue. While the credentials and qualifications of such experts may not always be subject to challenge, the reliability and relevance of their proffered testimony should be examined closely. Regardless of the conclusion generated, the inquiry into a mental health professional’s opinion must be one that looks to the principles and methods used, not the ultimate conclusion reached. Daubert v. Merrill Dow Pharmaceuticals, Inc., 509 U.S. 579, 595 (1993).
As with all experts, the testimony of mental health professionals must meet the minimum requirements established in Daubert and Kuhmo Tire Co. v. Carmichael, 526 U.S. 137 (1999) and their progeny. The test of admissibility is not whether a particular scientific opinion has the best foundation or is demonstrably correct; rather, it is whether the “particular opinion is based on valid reasoning and reliable methodology.” Oddi v. Ford Motor Co., 234 F. 3d 136, 146 (3d. Cir. 2000) (quoting Kannankeril v. Terminix Int’l, Inc., 128 F. 3d 802, 806 (3d Cir. 1997). Moreover, a court may admit questionable testimony if it “falls within ‘the range where experts might reasonably differ, and where the jury must decide among conflicting views …’” S.M. v. J.K., 262 F. 3d 914, 921 (9th Cir. 2001) (quoting Kuhmo, 526 U.S. at 153). As “‘mental health professionals involved in everyday practice may disagree more than half the time – even on major diagnostic categories such as schizophrenia and organic brain syndrome’” – courts are especially loathe to exclude their expert opinions. Id. (quoting Christopher Slobogin, Doubts about Daubert: Psychiatric Anecdata as a Case Study, 57 Wash. & Lee L. Rev. 919, 920 (2000)). There are numerous state and federal court opinions that discuss the admissibility of expert opinions from mental health professionals. This article will examine some of those decisions and discuss the evidentiary issues to watch for when evaluating the proffered testimony of psychiatrists and other mental health professionals.
