Assessing competency to waive Miranda rights in defendants with mental retardation.

Abstract

Criminal defendants with mental retardation face special problems in the process of interrogation and confession, particularly with regard to the knowing, intelligent, and voluntary waiver ofMiranda rights. Despite this, little attention has been paid to empirical measurement of this form of competency in mentally retarded adults. The present research uses scales originally developed by Grisso (1981) to measure competency to waive such rights in juveniles. Two samples of mentally retarded adults, one in a sheltered workshop setting and the other composed of current probationers, were tested. Both samples scored substantially lower on measures ofMiranda comprehension than Grisso's samples of juveniles and adults. There were also differences between the samples that appear attributable to differential levels of criminal justice experience. It is concluded that the Grisso scales may be helpful in determining competency to waiveMiranda rights in defendants with mental retardation. In addition, the present data raise strong concerns about the ability of many such defendants to make intelligentMiranda waivers. Policy recommendations are discussed.