Psychological Disorders: Understanding the Criteria for Admissibility of Expert Opinion

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.

Opinion as to Veracity and Truthfulness of Others

As with all expert testimony, one of the greatest dangers associated with the testimony of mental health professionals is that the finder of fact may abdicate its duty to evaluate evidence, deferring resolution of critical issues to expert opinion testimony. This is especially dangerous with psychiatry experts, whose opinions may touch upon the veracity of another individual. Although Federal Rule of Evidence 703 allows inadmissible evidence to be the basis of an expert's opinion where it is of the “type reasonably relied upon by experts in the particular field,” the Rule in no way purports to allow witnesses to assess the trustworthiness or accuracy of the testimony given in the same case or offer opinions based on such an assessment. United States v. Scop, 846 F. 2d 135, 143 (2d Cir. 1988). The credibility of a witness is exclusively the province of the trier of fact. Id. at 142. Although an expert witness with medical knowledge and skills related directly to credibility may be permitted to testify to relevant physical or mental conditions, he may not state an opinion as to whether another witness is credible.

In State v. Alberico, 861 P. 2d 192 (N.M. 1993), the Supreme Court of New Mexico addressed the admissibility of expert testimony in the case of an alleged sexual abuse victim suffering from Post-Traumatic Stress Disorder (PTSD). The court noted that one of the drawbacks to allowing evidence of PTSD was that the diagnosis relied upon the truthfulness of the alleged victim's reports to the examining psychiatrist. Id. at 210. The court pointed out, however, that any prejudice resulting from inaccurate or false self reporting could be cured by vigorous cross-examination, “addressing the point that the diagnosis is based upon what the complainant says, not upon an independent evaluation of her truthfulness.” Id.

Observing that expert testimony is admissible even if it touches upon an ultimate issue to be decided by the trier of fact, the court determined that evidence of the alleged victim's PTSD was probative and admissible to establish that the alleged victim exhibited symptoms of PTSD that were consistent with rape or sexual abuse. Id. The court noted, however, that while PTSD testimony could be offered to show that the alleged victim suffered from symptoms that were consistent with sexual abuse, it could not be offered to establish that the alleged victim was telling the truth. Id. at 251 (emphasis added). See also S.M. v. J.K., 262 F. 3d 914 (9th Cir. 2001) (allowing plaintiff's psychiatrist to testify to plaintiff's PTSD, as long as he did not express an opinion as to whether plaintiff was sexually assaulted or express an opinion as to her veracity); Isely v. Capuchin Province, 877 F. Supp. 1055, 1067 (E.D. Mich. 1995) (admitting psychologist's testimony that plaintiff's conduct and behavior were consistent with PTSD, repressed memory and with people who have suffered abuse); but see Figueroa v. Torres, No. Civil 01-1827 (SEC)(JA), 2003 U.S. Dist. LEXIS 10264, at * 8 (D. P.R. Jun. 16, 2003) (precluding report and testimony of defendants' psychiatrist because he did nothing more than “present[ ] a speculative argument that improperly judged Plaintiff's credibility” and because his opinion was unsupported by comprehensive scientific knowledge and the expert did not display the method he used to reach his opinion).

Although “vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence,” Daubert, 509 U.S. at 596, the expert testimony of a mental health professional may be precluded due to another veracity problem ' incomplete patient history. In Lassiegne v. Taco Bell Corp., 202 F. Supp. 2d 512 (E.D. La. 2002), the plaintiff brought suit against Taco Bell after choking on a chicken bone that was apparently contained in a chicken soft taco. The plaintiff, a police officer, claimed that he suffered from migraine headaches, impotency and PTSD as a result of the choking incident. Id. at 514. To be diagnosed as suffering from PTSD, an individual must meet six criteria, including: 1) the traumatic experience is persistently re-experienced; 2) persistent avoidance of stimuli associated with the trauma and numbing of general responsiveness (not present before the trauma); and 3) the disturbance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning. American Psychiatric Association, “Diagnostic & Statistical Manual of Mental Disorders” at 467-68 (4th rev. ed. 1994) (DSM-IV).

To support his claim, the plaintiff relied on the testimony of Randell Hess, a licensed clinical social worker with an expertise in stress, anxiety, depression and PTSD. Id. at 519. Hess opined that any kind of near death experience could cause PTSD, including choking on a chicken bone. He also testified that while he had considered a differential diagnosis for the plaintiff, including depression and acute stress disorder, he was able to rule out these diagnoses based on the criteria listed in the “Diagnostic & Statistical Manual of Mental Disorders” (DSM). The defendant moved to preclude Hess' testimony, arguing that Hess' diagnosis was unreliable because the plaintiff did not provide him with a complete patient history. The plaintiff failed to tell Hess that his brother suffered from depression and delusion and that his mother had committed suicide with his gun and he had discovered her body. Id. at 519-20. Moreover, Hess acknowledged that a family history of depression would have impacted his diagnosis of the plaintiff. Id. at 520.

Because the plaintiff had withheld key facts, the court determined that Hess' expert opinion and testimony was not based upon sufficient facts or data and was therefore inadmissible. Id. at 520. The court also noted that the undisclosed information could have had an impact on Hess' diagnosis, “particularly since he had to rule out depression as the source of plaintiff's problems in making a differential diagnosis.” Id. at 521. Moreover, the court was concerned that Hess “uncritically accepted plaintiff's account and failed to interpose much in the way of independent professional judgment in arriving at his conclusions.” Id. at 522. The court was hard pressed to find that the plaintiff, who had weathered the death of his brother and mother in less than 3 years, was traumatized for more than a year from choking on a chicken bone that did not even cause him to pass out. Id. Indeed, Hess diagnosed the plaintiff with PTSD, even though the plaintiff admitted that he still ate at the same Taco Bell and still ate chicken from fast food restaurants, actions that are contrary to a PTSD diagnosis. Id. at 520. The court noted that Hess clung to his PTSD diagnosis “in the face of mounting evidence of significant omissions” from plaintiff's self-reported history and failed to give an adequate reason as to why his opinion was valid. Id. at 522.

Use of the DSM-IV in Rendering an Opinion Is Not Mandatory

Since its introduction, the DSM has become widely accepted as the “common language” of mental health professionals for communicating about the disorders for which they have professional responsibility. See United States v. DiDomenico, 985 F. 2d 1159, 1167 (2d Cir. 1993). Although use of the DSM by mental health professionals is not always mandatory, its inappropriate use by an expert may result in the preclusion of that expert's opinion and testimony: An expert who does not apply reliable principles and methods to the facts and data with which he is presented cannot reasonably assist the trier of fact. Guzman v. Elena Ramirez De Arellano De Villoldo, 245 F. Supp. 2d 388, 394 (D. P.R. 2003).

In Guzman, the court precluded the testimony of plaintiffs' expert psychiatrist, although his clinical findings and diagnosis of “Major Depression with post-traumatic stress disorder features” was based on the DSM-IV. Noting that an expert who does not apply reliable principles and methods to the facts or data with which he is presented cannot reasonably assist the trier of fact, the court found that the DSM-IV was not “reliably applied to reach the diagnosis since there is no such diagnosis as Major Depression with post-traumatic stress disorder features.” Id. at 394. The court determined that allowing plaintiffs' psychiatrist to testify would serve only to confuse the jury. Id. at 395.

Other courts have determined that variation from the DSM's diagnostic criteria will not automatically result in an unreliable diagnosis. S.M. v. J.K., 262 F.3d 914, 922 (9th Cir. 2001). In S.M., the defendant argued that the testimony of plaintiff's expert psychiatrist should have been excluded at the trial court because the doctor did not strictly rely upon the relevant version of the DSM in reaching his diagnosis. Id. at 921. The court found that the trial court had not erred in allowing the psychiatrist's testimony, noting that the defendant had the opportunity to cross-examine the plaintiff's expert about the differences between his diagnosis and the two relevant versions of the DSM and to explore the possibility that the assault was not severe enough to trigger PTSD. Id. at 922.

A similar decision was reached in Sims v. Medical Center of Baton Rouge, Inc., et al., No. 96-3371, 1997 U.S. Dist. LEXIS 13163 (E.D. La. Aug. 22, 1997). In Sims, defendant Girau claimed that the plaintiff's expert, a board certified social worker, should not be allowed to testify regarding the plaintiff's alleged mental disorders. Id. at *2. Girau challenged the use of the DSM-IV by the plaintiff's expert, attacking her alleged misapplication of the DSM-IV and alleged misdiagnoses of dysthymia, adjustment disorder and generalized anxiety disorder. Noting that defense counsel was able to attack the expert's opinion without any expertise in the use of the DSM-IV or in psychiatric diagnosis generally, the court found “[i]f a lay person such as defense counsel can so confidently criticize [plaintiff's expert's] application of the DSM IV, surely a jury could as well … Girau's critiques should be addressed through vigorous cross examination, presentation of contrary evidence, and careful instruction on the burden of proof, not by excluding [the] testimony.” Id. at *8.

Conclusion

Although some courts are willing to preclude the expert testimony of mental health professionals that draws an ultimate conclusion as to the veracity of alleged victims and other individuals, many recognize that the court's role as “gatekeeper” cannot replace the traditional adversarial system. As a general rule, questions relating to the bases and sources of an expert's opinion affect the weight, rather than the admissibility, of an expert opinion. Daubert, 509 U.S. at 596. Even in cases in which the jury will be forced to parse through something as complex as the DSM, competing views must be weighed and assessed by the trier of fact. Katt v. City of New York, 151 F. Supp. 2d 313, 351 (S.D.N.Y. 2001). Courts are loath to preclude expert testimony and instead rely on the “vigorous cross examination” advocated in Daubert. While many courts may allow the jury to weigh expert testimony rather than exclude it altogether, it is important to examine the information upon which a psychiatric expert bases his opinion closely as omissions in patient history and misapplication of the DSM may provide an avenue for preclusion.

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.

Opinion as to Veracity and Truthfulness of Others

As with all expert testimony, one of the greatest dangers associated with the testimony of mental health professionals is that the finder of fact may abdicate its duty to evaluate evidence, deferring resolution of critical issues to expert opinion testimony. This is especially dangerous with psychiatry experts, whose opinions may touch upon the veracity of another individual. Although Federal Rule of Evidence 703 allows inadmissible evidence to be the basis of an expert's opinion where it is of the “type reasonably relied upon by experts in the particular field,” the Rule in no way purports to allow witnesses to assess the trustworthiness or accuracy of the testimony given in the same case or offer opinions based on such an assessment. United States v. Scop , 846 F. 2d 135, 143 (2d Cir. 1988). The credibility of a witness is exclusively the province of the trier of fact. Id. at 142. Although an expert witness with medical knowledge and skills related directly to credibility may be permitted to testify to relevant physical or mental conditions, he may not state an opinion as to whether another witness is credible.

In State v. Alberico , 861 P. 2d 192 (N.M. 1993), the Supreme Court of New Mexico addressed the admissibility of expert testimony in the case of an alleged sexual abuse victim suffering from Post-Traumatic Stress Disorder (PTSD). The court noted that one of the drawbacks to allowing evidence of PTSD was that the diagnosis relied upon the truthfulness of the alleged victim's reports to the examining psychiatrist. Id. at 210. The court pointed out, however, that any prejudice resulting from inaccurate or false self reporting could be cured by vigorous cross-examination, “addressing the point that the diagnosis is based upon what the complainant says, not upon an independent evaluation of her truthfulness.” Id.

Observing that expert testimony is admissible even if it touches upon an ultimate issue to be decided by the trier of fact, the court determined that evidence of the alleged victim's PTSD was probative and admissible to establish that the alleged victim exhibited symptoms of PTSD that were consistent with rape or sexual abuse. Id. The court noted, however, that while PTSD testimony could be offered to show that the alleged victim suffered from symptoms that were consistent with sexual abuse, it could not be offered to establish that the alleged victim was telling the truth. Id. at 251 (emphasis added). See also S.M. v. J.K., 262 F. 3d 914 (9th Cir. 2001) (allowing plaintiff's psychiatrist to testify to plaintiff's PTSD, as long as he did not express an opinion as to whether plaintiff was sexually assaulted or express an opinion as to her veracity); Isely v. Capuchin Province, 877 F. Supp. 1055, 1067 (E.D. Mich. 1995) (admitting psychologist's testimony that plaintiff's conduct and behavior were consistent with PTSD, repressed memory and with people who have suffered abuse); but see Figueroa v. Torres, No. Civil 01-1827 (SEC)(JA), 2003 U.S. Dist. LEXIS 10264, at * 8 (D. P.R. Jun. 16, 2003) (precluding report and testimony of defendants' psychiatrist because he did nothing more than “present[ ] a speculative argument that improperly judged Plaintiff's credibility” and because his opinion was unsupported by comprehensive scientific knowledge and the expert did not display the method he used to reach his opinion).

Although “vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence,” Daubert, 509 U.S. at 596, the expert testimony of a mental health professional may be precluded due to another veracity problem ' incomplete patient history. In Lassiegne v. Taco Bell Corp., 202 F. Supp. 2d 512 (E.D. La. 2002), the plaintiff brought suit against Taco Bell after choking on a chicken bone that was apparently contained in a chicken soft taco. The plaintiff, a police officer, claimed that he suffered from migraine headaches, impotency and PTSD as a result of the choking incident. Id. at 514. To be diagnosed as suffering from PTSD, an individual must meet six criteria, including: 1) the traumatic experience is persistently re-experienced; 2) persistent avoidance of stimuli associated with the trauma and numbing of general responsiveness (not present before the trauma); and 3) the disturbance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning. American Psychiatric Association, “Diagnostic & Statistical Manual of Mental Disorders” at 467-68 (4th rev. ed. 1994) (DSM-IV).

To support his claim, the plaintiff relied on the testimony of Randell Hess, a licensed clinical social worker with an expertise in stress, anxiety, depression and PTSD. Id. at 519. Hess opined that any kind of near death experience could cause PTSD, including choking on a chicken bone. He also testified that while he had considered a differential diagnosis for the plaintiff, including depression and acute stress disorder, he was able to rule out these diagnoses based on the criteria listed in the “Diagnostic & Statistical Manual of Mental Disorders” (DSM). The defendant moved to preclude Hess' testimony, arguing that Hess' diagnosis was unreliable because the plaintiff did not provide him with a complete patient history. The plaintiff failed to tell Hess that his brother suffered from depression and delusion and that his mother had committed suicide with his gun and he had discovered her body. Id. at 519-20. Moreover, Hess acknowledged that a family history of depression would have impacted his diagnosis of the plaintiff. Id. at 520.

Because the plaintiff had withheld key facts, the court determined that Hess' expert opinion and testimony was not based upon sufficient facts or data and was therefore inadmissible. Id. at 520. The court also noted that the undisclosed information could have had an impact on Hess' diagnosis, “particularly since he had to rule out depression as the source of plaintiff's problems in making a differential diagnosis.” Id. at 521. Moreover, the court was concerned that Hess “uncritically accepted plaintiff's account and failed to interpose much in the way of independent professional judgment in arriving at his conclusions.” Id. at 522. The court was hard pressed to find that the plaintiff, who had weathered the death of his brother and mother in less than 3 years, was traumatized for more than a year from choking on a chicken bone that did not even cause him to pass out. Id. Indeed, Hess diagnosed the plaintiff with PTSD, even though the plaintiff admitted that he still ate at the same Taco Bell and still ate chicken from fast food restaurants, actions that are contrary to a PTSD diagnosis. Id. at 520. The court noted that Hess clung to his PTSD diagnosis “in the face of mounting evidence of significant omissions” from plaintiff's self-reported history and failed to give an adequate reason as to why his opinion was valid. Id. at 522.

Use of the DSM-IV in Rendering an Opinion Is Not Mandatory

Since its introduction, the DSM has become widely accepted as the “common language” of mental health professionals for communicating about the disorders for which they have professional responsibility. See United States v. DiDomenico , 985 F. 2d 1159, 1167 (2d Cir. 1993). Although use of the DSM by mental health professionals is not always mandatory, its inappropriate use by an expert may result in the preclusion of that expert's opinion and testimony: An expert who does not apply reliable principles and methods to the facts and data with which he is presented cannot reasonably assist the trier of fact. Guzman v. Elena Ramirez De Arellano De Villoldo , 245 F. Supp. 2d 388, 394 (D. P.R. 2003).

In Guzman, the court precluded the testimony of plaintiffs' expert psychiatrist, although his clinical findings and diagnosis of “Major Depression with post-traumatic stress disorder features” was based on the DSM-IV. Noting that an expert who does not apply reliable principles and methods to the facts or data with which he is presented cannot reasonably assist the trier of fact, the court found that the DSM-IV was not “reliably applied to reach the diagnosis since there is no such diagnosis as Major Depression with post-traumatic stress disorder features.” Id. at 394. The court determined that allowing plaintiffs' psychiatrist to testify would serve only to confuse the jury. Id. at 395.

Other courts have determined that variation from the DSM's diagnostic criteria will not automatically result in an unreliable diagnosis. S.M. v. J.K., 262 F.3d 914, 922 (9th Cir. 2001). In S.M., the defendant argued that the testimony of plaintiff's expert psychiatrist should have been excluded at the trial court because the doctor did not strictly rely upon the relevant version of the DSM in reaching his diagnosis. Id. at 921. The court found that the trial court had not erred in allowing the psychiatrist's testimony, noting that the defendant had the opportunity to cross-examine the plaintiff's expert about the differences between his diagnosis and the two relevant versions of the DSM and to explore the possibility that the assault was not severe enough to trigger PTSD. Id. at 922.

A similar decision was reached in Sims v. Medical Center of Baton Rouge, Inc., et al., No. 96-3371, 1997 U.S. Dist. LEXIS 13163 (E.D. La. Aug. 22, 1997). In Sims, defendant Girau claimed that the plaintiff's expert, a board certified social worker, should not be allowed to testify regarding the plaintiff's alleged mental disorders. Id. at *2. Girau challenged the use of the DSM-IV by the plaintiff's expert, attacking her alleged misapplication of the DSM-IV and alleged misdiagnoses of dysthymia, adjustment disorder and generalized anxiety disorder. Noting that defense counsel was able to attack the expert's opinion without any expertise in the use of the DSM-IV or in psychiatric diagnosis generally, the court found “[i]f a lay person such as defense counsel can so confidently criticize [plaintiff's expert's] application of the DSM IV, surely a jury could as well … Girau's critiques should be addressed through vigorous cross examination, presentation of contrary evidence, and careful instruction on the burden of proof, not by excluding [the] testimony.” Id. at *8.

Conclusion

Although some courts are willing to preclude the expert testimony of mental health professionals that draws an ultimate conclusion as to the veracity of alleged victims and other individuals, many recognize that the court's role as “gatekeeper” cannot replace the traditional adversarial system. As a general rule, questions relating to the bases and sources of an expert's opinion affect the weight, rather than the admissibility, of an expert opinion. Daubert, 509 U.S. at 596. Even in cases in which the jury will be forced to parse through something as complex as the DSM, competing views must be weighed and assessed by the trier of fact. Katt v. City of New York , 151 F. Supp. 2d 313, 351 (S.D.N.Y. 2001). Courts are loath to preclude expert testimony and instead rely on the “vigorous cross examination” advocated in Daubert. While many courts may allow the jury to weigh expert testimony rather than exclude it altogether, it is important to examine the information upon which a psychiatric expert bases his opinion closely as omissions in patient history and misapplication of the DSM may provide an avenue for preclusion.