Competence to waive interrogation rights and adjudicative competence in adolescent defendants: cognitive development,...

Although there is growing evidence of developmental differences in competency to waive interrogation rights and adjudicative competence, the correlates of adolescents' legal capacities remain unclear. This study examined the relationship of legal capacities to cognitive development, legal learning opportunities, and psychological symptoms. Participants were 152 male and female defendants aged 11-17, who completed Grisso's Instruments for Assessing Understanding and Appreciation of Miranda Rights, the Fitness Interview Test (Revised Edition), the Woodcock-Johnson III Cognitive Assessment Battery, and the Brief Psychiatric Rating Scale for Children. Legal capacities relevant to interrogation and adjudication increased with age. These developmental differences were partially mediated or explained by cognitive development. Of the specific cognitive abilities examined (general intellectual ability, verbal ability, reasoning, long-term retrieval, attention, and executive functioning), verbal ability was a particularly strong predictor of performance on competency measures. Also, defendants obtained lower scores on competency measures if they showed evidence of attention deficits or hyperactivity, had spent limited time with their attorneys, and/or were from low socioeconomic backgrounds.