The Relationship of Competency to Stand Trial and Criminal Responsibility

Abstract

Mental health professionals have been accused of confusing the constructs of competency to stand trial and criminal responsibility with each or with a third construct such as psychosis. This investigation examined the relationship between decisions about competency to stand trial and criminal responsibility in a sample of 121 defendants admitted to a state hospital for pretrial evaluation. In addition, the investigation examined correlates of the two kinds of decisions using demographic data, measures of cognitive functioning and psychopathology, and a rating of crime severity. Conclusions about the empirical relationship between competency and responsibility judgments were precluded because examiners classified most incompetent defendants as “undetermined” on the issue of criminal responsibility. Nevertheless, interesting differences in the correlates of the two legal decisions were obtained. Competency decisions showed modest but significant correlations with performance on a test of competency abilities, a measure of intellectual functioning, and psychiatric diagnosis. Responsibility decisions were most strongly correlated with two indices of psychopathology-psychiatric diagnosis and the presence of hallucinations and delusions.