The MacCAT-CA and the ECST-R in Competency to Stand Trial Evaluations: A Critical Review and Practical Implications

There is debate regarding the utility of standardized instruments in the assessment of competence to stand trial (CST). Though the field generally has a positive view of the second-generation nomothetic instruments available, the frequency of use falls far behind this favorable impression. The current paper reviewed two standardized instruments used in CST evaluations, the Evaluation of Competency to Stand Trial - Revised (ECST-R) and the MacArthur Competence Assessment Tool-Criminal Adjudication (MacCAT-CA). We first review the psychometric properties of both instruments, including a review of limitations. Next, we discuss the legal standing of both instruments, including a review of past admissibility challenges and a discussion of potential issues in cross-examination. Finally, we end with practical guidance for clinicians; namely, that these instruments are generally valid indicators of competence to stand trial and are likely to be particularly useful in cases where competence is ambiguous and the clinician would benefit from additional standardized data to make a clear clinical decision.