Mentally ill and non-mentally ill defendants' abilities to understand information
relevant to adjudication: a preliminary study.
S. K. Hoge, N. Poythress, R. Bonnie, M. Eisenberg, J. Monahan, T. Feucht-Haviar and L.
Bull. Amer. Acad. Psychiatry & the Law
24(2): 187-97, 1996.
The legal construct of competence to stand trial, or "adjudicative competence," is based on the
premise that some mentally disordered defendants have impaired abilities when compared with most
defendants and that adjudication should be barred if these competence-related abilities are
significantly impaired. Where the line is drawn between sufficient and insufficient abilities has
important consequences: as a result of being adjudicated incompetent, defendants may be detained
and treated involuntarily and their trials will be delayed. However, no studies have systematically
compared the capacities of relevant groups of defendants. In this study, 84 criminal defendants--42
of whom were hospitalized as incompetent and 42 of whom were regarded as unquestionably
competent--were administered three instruments measuring capacity to understand legally relevant
information. Incompetent defendants performed more poorly on all measures of understanding.
Twenty-eight incompetent defendants were administered the measures a second time, after
restoration to competence. Restored defendants improved their performance on all measures of
understanding and their performance was similar to that of normal, competent defendants.