A new research instrument, the MacArthur Structured Assessment of Competencies of Criminal Defendants (MacSAC-CD), was administered to three groups of women defendants: those adjudicated incompetent and committed to forensic hospitals for treatment (n = 38), jail inmates receiving mental health treatment (n = 18) who had not been adjudicated incompetent, and randomly selected jail inmates (n = 50). Measures of the competence-related abilities of understanding and reasoning were found to have satisfactory indices of internal consistency (coefficient alpha), and all measures correlated in the expected direction with measures of global psychopathology, psychoticism, and verbal cognitive functioning. Between-group mean scores were all in the expected direction and were statistically significant for four of seven measures. No differences in MacSAC-CD performance were found in comparisons of male and female defendants who had been adjudicated incompetent, nor were differences found in the performance of male and female jail inmates.

Richard J. Bonnie et al., The Competence-Related Abilities of Women Criminal Defendants, 26 Journal of the American Academy of Psychiatry and the Law 215–22 (1998).