Psychiatric Evidence in Criminal Trials: To Junk or Not to Junk?
Slobogin, Christopher, William and Mary Law Review
If nothing else, the interaction between the criminal courtroom and the mental health profession has produced some memorable nomenclature. "The abuse excuse,"(1) "battered woman syndrome,"(2) "child sexual abuse accommodation syndrome,"(3) "false memory syndrome,"(4) "television intoxication,"(5) "urban survival syndrome,"(6) "XYY chromosome abnormality"(7)--these are just a few of the colorful appellations used to describe claims that mental health professionals have bolstered with their testimony over the years.(8) From reading the popular press, one could easily come to the conclusion that such testimony is spurious "psychobabble" that will eventually swallow up our justice system.(9) Even a more tempered observer is likely to wonder whether this type of opinion evidence is worthy of consideration in courts of law. That is the primary question this Article seeks to address.(10)
This Article begins, in Part I, with a brief review of the past four decades(11) of psychiatric and psychological testimony in criminal trials (henceforth referred to simply as "psychiatric testimony"). Although this review cannot be called comprehensive,(12) it does make clear that, contrary to what the popular literature would have us believe, psychiatric innovation is neither at an all time high nor the prevalent form of opinion testimony by mental health professionals. At the same time, such "nontraditional" expert opinion from clinicians, on those rare occasions when it does occur, has changed over the past few decades in both content and objective.
Part II canvasses historical developments in the law governing the admissibility of psychiatric testimony. With the Supreme Court's recent decision in Daubert v. Merrell Dow Pharmaceuticals,(13) this law has undergone a metamorphosis, at least on the surface. What is also clear, however, is that evidentiary changes have not, to date, affected the admissibility of most psychiatric testimony. Traditional psychiatric testimony continues to be admitted regardless of its reliability. Further, while novel psychiatric testimony is usually subjected to Daubert-type or other screening tests, the continuing ambiguity of these tests means that nontraditional evidence is still admitted, excluded, or limited in its scope for reasons that are not always immediately apparent. A better method of parsing out truly "junk" testimony is needed.
Part III offers ways of improving the evidentiary analysis. A good framework for such analysis already exists--under the Federal Rules of Evidence, the admissibility of any expert testimony hinges on its materiality, probative value, helpfulness, and understandability.(14) Most courts, however, perhaps not attuned to the subtly different versions of behavioral "science," could benefit from an elaboration of this framework as it applies to psychiatric testimony.
The most important contention in Part III concerns the assessment of probative value. The thesis here is that a distinction should be made between psychiatric evidence presented to prove past mental state and psychiatric evidence proffered to prove acts. Given the difficulty, in theory and in practice, of proving past mental state,(15) the reliability assessment that is part of gauging probative value should be less demanding for psychiatric evidence on this issue. At the same time, psychiatric testimony that focuses on whether an act occurred--an objective and scientifically verifiable fact--should have to meet a more stringent test. In short, assessment of probative value should take into account the extent to which accuracy is possible.
Part III also makes suggestions aimed at improving analysis of the other three components of the admissibility framework: materiality, helpfulness, and countervailing factors. First, courts should pay much closer attention to the substantive scope of the law governing mental state defenses, a move that should curtail some of the more outlandish claims. …