Date of Award


Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Doctor of Philosophy (PhD)




Geoffrey L. Thorpe

Second Committee Member

Jeffrey E. Hecker

Third Committee Member

Douglas Nangle


Like past studies (Cooper & Zapf, 2003; Heilbrun, 2001; Nicholson & Kugler, 1991; Robertson et al., 1997; Warren et al., 1991; Zapf & Roesch, 1998), the current study aimed to identify the clinical and legal factors associated with evaluators' recommendation of incompetence. The current study approached this task by utilizing modern test theory analyses in an attempt to identify not only the factors, but also specific symptoms related to adjudicative competence. Previous researchers have suggested that along with mental status and legal knowledge, a defendant's background history may be somewhat related to adjudicative competence (Zapf & Roesch, 2009). Hence, the current study divided all variables into three subscales: mental health history, mental status, and legal knowledge. A Coding Encyclopedia was developed for use in this study using inter-rater reliability for two independent raters in a stratified manner. The intra-class correlation coefficients for 50 of the first 100 and 20 of the second 100 evaluations exceeded the modest cutoff of .6 with the majority exceeding .9 agreement, illustrating acceptable inter-rater reliability with use of the Coding Encyclopedia (Elder, Pavalko, & Clipp, 1993). A total of 221 evaluations gathered from the state of Maine's State Forensic Service were included in the current study with 12 excluded due to concerns regarding motivational issues. Modern test theory analyses indicated that various areas typically assessed in a mental status evaluation are related to the latent trait of incompetence including: disorganized speech, labile and inappropriate affect, and delusions. The results also suggest that the areas of legal knowledge considered were all related to the latent trait of incompetence with the exception of the defendant knowing his/her lawyer's name, suggesting this area to be the most informative in adjudicative competency evaluations. Results also suggest that mental health history may help to inform recommendations regarding competency status but are unrelated to the latent trait of incompetence, instead are related to the symptoms assessed in the mental status evaluation. Limitations and future directions are also discussed.