Evaluating Juvenile Detainees' Miranda Misconceptions: The Discriminant Validity of the Juvenile Miranda Quiz

Most juvenile arrestees in custodial settings waive their Miranda rights almost immediately, and many then provide incriminating statements, if not outright confessions. Forensic practitioners are then asked to provide retrospective determinations regarding whether these waivers were effectuated knowingly, voluntarily, and intelligently. At present, the forensic assessment instrument for juvenile Miranda issues consists of the Miranda Rights Comprehension Instruments (MRCI)-which as its name implies-focuses mostly on Miranda comprehension with a de-emphasis of Miranda reasoning. In partially addressing this gap, the current study investigated the clinical utility of the Juvenile Miranda Quiz (JMQ) for evaluating key Miranda misconceptions, a critically important component of Miranda reasoning. Using data from 201 juvenile detainees, we evaluated the JMQ's discriminability with regards to cognitive variables and MRCI scales. Many moderate effect sizes in the predicted direction were found for the JMQ Primary Total and Juvenile Total scores. Finally, these detainees were tested using a mock crime scenario with a representative Miranda warning plus a brief interrogation to evaluate whether they would waive their rights, and if so, whether they would confess. Using Miranda measures to predict problematic outcomes (i.e., impaired waivers followed by confessions), the JMQ Juvenile Total proved the most successful. These findings are discussed within the context of the "intelligent" prong of Miranda waivers.