Opinion formation in evaluating the adjudicative competence and restorability of criminal defendants: a review of 8,000 evaluations.

Evaluations of competence to stand trial (CST) are the most common type of criminal forensic evaluation conducted, and courts tend to defer to clinician opinions regarding a defendant's competence. Thus, it is important to study the ways in which clinicians arrive at opinions regarding adjudicative competence and the data they consider in forming their opinions. We reviewed 8,416 evaluations conducted by forensic evaluators in Virginia over a 12 year period, and examined (a) the clinical, demographic, and criminal characteristics of a defendant as related to opinions regarding competence, predicted restorability, and impairment on "prongs" of the Dusky standard, (b) process and outcome differences in evaluations conducted by psychiatrists versus psychologists and inpatient versus outpatient evaluators, and (c) the consistency of incompetence base rates over a 10 year period. Overall, clinicians opined that 19% of defendants were incompetent and considered 23% of these unlikely to be restored to competence. Not surprisingly, psychotic and organic/intellectual disorders were most strongly associated with findings of incompetence. However, there were some notable differences between evaluations by psychologists versus psychiatrists and between evaluations conducted in inpatient versus outpatient settings.