Detecting the Differences in Miranda Abilities Between Individuals with and without Intellectual Disability
Objective: Although Miranda v. Arizona (1966) enacted safeguards for individuals entering custodial situations, existing research suggests that most individuals do not understand these protections. The purpose of this study was to evaluate the differences in Miranda abilities and response styles between a group of individuals with intellectual disability (ID) and a group without ID, which would clarify areas of vulnerability for individuals with ID. Additional goals were to determine if intelligence was an accurate predictor of these abilities, and to assess whether self-rated confidence was related to comprehension of Miranda. Hypotheses: The individuals without ID were expected to demonstrate significantly better Miranda abilities than the individuals with ID. Intelligence, specifically verbal intelligence, was expected to be an accurate predictor of knowledge, recall, acquiescence, and vocabulary. When comparing the two groups, it was hypothesized that confidence would relate to comprehension when controlling for the presence of ID. Method: Sixty-two individuals with ID and 23 individuals without ID completed the Wechsler Adult Intelligence Scale– 4th ed., the Standard Assessment of Miranda Abilities, and a background questionnaire. Results: The group without ID demonstrated better recall, knowledge, and vocabulary, whereas the ID group demonstrated more acquiescence. Analyses involving intelligence were limited, but intelligence was significantly related to recall, response style, and vocabulary with verbal intelligence demonstrating relationships with recall and vocabulary. Confidence was not related to Miranda knowledge. Conclusions: Individuals with ID are at a significant disadvantage in custodial situations due to poor Miranda abilities. Systematic modifications are recommended to rectify these vulnerabilities.