Conceptual Hurdles in the Application of Atkins v. Virginia

In its 2002 decision in Atkins v. Virginia, the United States Supreme Court held that the Eighth Amendment's prohibition against cruel and unusual punishment precludes the execution of "mentally retarded offender[s]." Writing for a six-member majority, Justice Stevens concluded that social attitudes and legal trends had shifted sufficiently in the thirteen years since the Court upheld such executions in Penry v. Lynaugh to justify a reversal of Penry. Indeed, according to Justice Stevens, during this interval, a social consensus had emerged favoring an absolute ban on the imposition of the death penalty on "a mentally retarded criminal." To reach this decision, the Court applied the standard set forth in its Eighth Amendment jurisprudence: that "evolving standards of decency [marking] the progress of a maturing society" inform its determination of whether a particular penalty - such as a death sentence imposed on a mentally retarded individual - constitutes cruel and unusual punishment. In Atkins, the Supreme Court took the unusual step of transforming a specific clinical diagnosis into the ultimate legal issue by making a diagnosis of "mental retardation" dispositive of death penalty ineligibility. Despite the apparent "bright-line" clarity of an absolute ban on the execution of mentally retarded offenders, the determination of which offenders fall within the protected group is deceivingly complex. The Court's observation that, "[t]o the extent there is serious disagreement about the execution of mentally retarded offenders, it is in determining which offenders are in fact retarded," was perhaps even more prescient than Justice Stevens realized. Much post-Atkins litigation has involved disputes about whether a particular defendant is or is not "mentally retarded." This result is not surprising in that the Atkins Court elevated the question of whether a defendant is found to be "mentally retarded" to the status of a life or death matter. While the spirit of the Court's decision in Atkins is unquestionably humane and compassionate, the implementation of Atkins raises new challenges with this singular reliance on clinical judgments about whether an individual is or is not "mentally retarded." The Court provided some guidance, however. It cited to two commonly-accepted definitions of "mental retardation," both of which rely on evaluations of "intellectual functioning" and "adaptive behavior." States need not be bound by these definitions, however. The Court explicitly granted states discretion to determine precisely how to comply with the constitutional mandate announced in Atkins. Yet, the meanings of the concepts of "mental retardation," "intelligence," and "adaptive behavior" are - like the standards of decency guiding the Court - continually evolving, and are subjects of ongoing reevaluation and debate among scientists, theorists, and professionals. Shifts in nomenclature illustrate this phenomenon. For example, in 2006 the American Association of Mental Retardation ("AAMR") changed its name to the American Association on Intellectual and Developmental Disabilities ("AAIDD"), and made corresponding changes to the names of its journals as well. AAIDD notes that the new language reflects a critical shift in the perspectives of researchers, professionals, and others about what is now referred to as "intellectual disability." Experts suggest that "[t]he field of mental retardation is in a period of great flux and transition" and notions of what constitutes "mental retardation" are changing. If so, we must confront the normative question of which conceptualizations should guide the assessment in Atkins evaluations. The last several decades have witnessed bold challenges to predominant concepts of "intelligence" which have important implications for how practitioners measure intellectual functioning. And, the concept of "adaptive functioning," the undervalued companion to "intellectual functioning" in modern definitions of "mental retardation," is also undergoing reevaluation. Given what is at stake in Atkins assessments, lawmakers, jurists, practitioners, and others must confront the question of how to comply responsibly with the Court's mandate in Atkins in light of the continual evolution of the knowledge, concepts, and practices relevant to its implementation. This Article identifies some of the conceptual challenges inherent in determining who is and who is not "mentally retarded" for the purpose of applying the U.S. Supreme Court's 2002 decision in Atkins v. Virginia. It begins with an examination of the Supreme Court's articulation in Atkins of its rationales for excluding "mentally retarded" persons from the reach of the death penalty. It continues with a discussion of current notions and recent reformulations of "mental retardation," "intelligence," and "adaptive behavior." Next, it sets forth certain key principles of psychological assessment and then, more specifically, psycholegal assessments (i.e., psychological assessments conducted with the purpose of informing a legal decision), noting the convergence of the more progressive notions of "mental retardation" and its measurement, and modern principles of psycholegal assessment. It then contrasts the approaches of two states - Florida and California - to implementing Atkins and comments on how each approach fares in light of the principles guiding the conduct of valid psycholegal assessments. These analyses lead to the conclusion that for some defendants-particularly those viewed as "mildly mental retarded" - summary scores on traditional measures of intellectual and adaptive functioning will not constitute the most meaningful and relevant evidence of their disability for the purpose of death-penalty exclusion. Some defendants who are significantly intellectually impaired in ways highlighted by the Atkins Court will not be identified as "mentally retarded" on the basis of these scores, and may therefore be sentenced to death. Efforts to develop more appropriate evaluative approaches are necessary and should be grounded in modern models of psycholegal assessment guided by progressive constructions of concepts of "intelligence," "intellectual disability," and related psychological variables discussed in this Article. Until such approaches are developed, courts must recognize the limitations of existing measurement instruments. In light of the severity and finality of the death penalty, state policies should err on the side of casting a net that is too wide rather than one that is too narrow in defining "mental retardation" for the purpose of Atkins compliance. Recommendations as to the appropriate criteria are set forth in this Article's Conclusion.