THE MACARTHUR ADJUDICATIVE COMPETENCE STUDY - DIAGNOSIS, PSYCHOPATHOLOGY, AND COMPETENCE-RELATED ABILITIES

A set of measures assessing abilities related to legal standards for c ompetence in the adjudicative process were administered to mentally-di sordered criminal defendants with diagnoses of schizophrenia, affectiv e disorder, other psychiatric disorders, and to criminal defendants wi thout diagnosed mental disorder. Mentally-disordered defendants were r ecruited from two groups: those who had been committed for restoration of competence and those who had been identified by jail personnel as mentally ill. Significant impairments in competence-related abilities were found for approximately half of the defendants with schizophrenia . Defendants with schizophrenia scored lower on measures of understand ing, reasoning, and appreciation related to the adjudication process. The association between symptoms and competence-related abilities was explored within diagnostic groups. Conceptual disorganization was foun d to be inversely correlated with performance on all measures in both defendants with schizophrenia and those with affective disorders. For other psychotic symptoms, differing patterns-of correlations were foun d in the two major diagnostic;groups, The implications for policy desi gned to safeguard the rights of defendants to be tried while competent are discussed. (C) 1997 John Wiley & Sons, Ltd.