Forensic Expert Testimony Must Not Be Excluded On the Basis of the Expert's Opinion Alone
In U.S. v. Ray, 956 F.3d 1154 (9th Cir. 2020), the U.S. Court of Appeals for the Ninth Circuit ruled that the U.S. District Court for the Central District of California had abused its discretion in excluding expert testimony offered as part of an insanity defense. The Ninth Circuit found that the district court erred by focusing on the proposed expert's opinion rather than considering whether the expert's testimony would have helped the trier of fact make its own decision.
Facts of the Case
In October 2016, Patrick Bacon and Daniel Ray, inmates at the Victorville Federal Prison in California, coordinated an assault of a fellow prison inmate. Mr. Bacon used a knife concealed within a book provided by Mr. Ray to inflict nonfatal stab wounds to the inmate's chest and head. The assault and its preparation were recorded by prison security cameras. Mr. Bacon and Mr. Ray were charged with assault with a deadly weapon with intent to do bodily harm and assault causing serious bodily injury.
Prior to trial, Mr. Bacon notified the court of his intent to present an insanity defense. In support of the defense, he submitted a report by a forensic psychologist who evaluated Mr. Bacon in December 2017. In his report, the psychologist documented a history of Mr. Bacon's behavioral problems and treatment starting in 2003. He opined that Mr. Bacon experienced “myriad” mental health problems, that at the time of the assault there were “elements of a downward spiral of isolation, depression, paranoia, and anxiety that resulted in a dissociative state” (Ray, p 1157), and that, as a result, Mr. Bacon would have had “difficulty understanding the nature and quality of his action at the time of the offense conduct” (Ray, p 1157).
The government moved to preclude the psychologist's testimony on the grounds that it was unreliable and irrelevant. They argued that the psychologist did not opine that Mr. Bacon had a specific severe mental disease or defect at the time of the offense and that his opinion about a dissociative state was not supported by medical literature. They also noted that the psychologist did not explain the tests he administered, their results, or their relationship to his conclusions.
The district court granted the motion to preclude the psychologist's testimony, holding that under Fed. R. Evid. 702 (2016), the psychologist's opinion was not relevant. The court found the psychologist's conclusion unhelpful to the trier of fact in facilitating understanding of the evidence or determining the question of sanity because the psychologist did not opine that Mr. Bacon was “unable, as opposed to had difficulty understanding or appreciating the nature and quality” (Ray, p 1158) of the assault. Mr. Bacon was unable to present an insanity defense. A jury found Mr. Bacon and Mr. Ray guilty of their charges. Mr. Bacon was sentenced to 10 years in prison and Mr. Ray to eight years and four months. Mr. Bacon appealed.
Ruling and Reasoning
The U.S. Court of Appeals for the Ninth Circuit considered whether the district court had abused its discretion in precluding the defense's expert testimony and whether the exclusion of the expert's testimony was harmless. The court ruled that the district court had abused its discretion in excluding the expert and that doing so was not harmless. The court vacated Mr. Bacon's conviction and remanded the case to the district court for a new trial.
With respect to the abuse of discretion, the appellate court found that the district court had applied the wrong standard in barring the expert witness testimony. The court wrote that the district court's focus on the relevance of the psychologist's “bottom-line opinions” was erroneous (Ray, p 1159). Instead, the district court should have considered the relevance of the psychological evaluation in aiding the trier of fact.
The court ruled the exclusion was not harmless because the expert's testimony might have supported an insanity defense for Mr. Bacon and might have changed his verdict. In addition, the court clarified that the district court did not have to admit the psychologist's testimony in the new trial.
Concurring Opinion
In a concurring opinion, three judges expressed concern about the requirement for a new trial. They stated that if the district court were to find the psychologist's opinion inadmissible again under a different rationale, a jury would hear the same evidence as during the first trial. The second trial would therefore be “wasteful of judicial resources” (Ray, p 1161). A potential solution, that the district court first rule on whether the disputed testimony was admissible before requiring a new trial, previously proposed by Judge Nguyen in her dissent in Estate of Barabin v. AstenJohnson Inc., 740 F.3d 457 (9th Cir. 2014), was prohibited on the basis of existing precedent.
Discussion
This case revisits fundamental questions about the admissibility of expert testimony. The federal rules of evidence require that expert testimony be the product of “reliable principles and methods” that are “reliably applied” (Fed. R. Evid. 702 (2016)). The nonexclusive list of criteria for reliability articulated in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993) offers some guidance for judges and experts; for example, whether the methodology used to form an opinion is accepted by a professional community. Psychiatric expert opinions, however, are not individually testable nor subject to peer review, and no known error rates exist. Reasonable practitioners can and do disagree. There are also no standards controlling how to answer the wide variety of forensic questions that an expert may encounter. Although the American Academy of Psychiatry and the Law publishes practice documents for forensic psychiatric assessments in general and for common consultation questions, these guidelines makes clear that the recommendations “do not set a standard of practice” and highlight the importance of other training, research, and experience (AAPL Practice Guideline for the Forensic Assessment. J Am Acad Psychiatry Law 43:S3–53, 2015, p S3). Therefore, courts' discretion is tempered by the expectation that “shaky but admissible” evidence be evaluated by the trier of fact with cross-examination and contrary evidence (Daubert, p 596).
Some parameters of reliable examination methodology have been articulated in the literature on forensic assessment quality improvement. Accepted metrics for assessment methodology include the use of data sources other than the interview or review of prior medical and psychiatric records. Essential components of written reports are the inclusion of both a clearly stated opinion and explanatory text linking the assessment findings to these conclusions. If some aspects of forensic methodology were codified as indicative of reliable practice, the court may be more easily able to identify helpful testimony.
- © 2021 American Academy of Psychiatry and the Law
