Investigating the effects of repeated Miranda warnings: do they perform a curative function on common Miranda misconceptions?

In Miranda v. Arizona (1966), the Supreme Court of the United States required that custodial suspects be apprised of their Constitutional rights against self-incrimination. The Court could not have anticipated the rampant popularization of Miranda warnings in subsequent movies and television dramas. Influenced by public media, many arrestees assume that they already "know" their rights, with no awareness of their misconceptions. The current investigation examines whether repeated exposures to Miranda warnings performs any "curative" function (i.e., dispelling common Miranda misconceptions held by pretrial defendants). The accumulative effects of five different Miranda warnings were tested over a several-hour period on 260 detainees. For the nearly half (113 or 43.5%) with three or more misconceptions, improvement (i.e., ≥2 fewer misconceptions) occurred for only 35 defendants. Predictably, this improved group also tended to display a better understanding of Miranda-relevant vocabulary words and a better recall of the administered Miranda warnings than their unimproved counterparts. On average, the improved group also performed better on general measures of intelligence, and listening and reading comprehension, while still evidencing substantial cognitive deficits. The curative function of Miranda advisements is considered in light of these findings.