John H. Blume

Implementing (or Nullifying) Atkins?: The Impact of State Procedural Choices on Outcome in Capital Cases Where Intellectual Disability is at Issue

This empirical study assesses the impact of state procedural choices on the implementation of Atkins v. Virginia, which prohibits the execution of prisoners with intellectual disability (“mental retardation”). Since Atkins, much scholarly attention, including our own, has focused on the manner in which states have applied substantive definitions of intellectual disability that deviate from the clinical norm. But as the present study shows, matters of procedure - such as whether a judge or jury determines intellectual disability, whether the determination occurs prior to trial or in conjunction with a capital sentencing trail, and the applicable burden of proof - may also make a difference on outcome. The study draws from available data on all known post-Atkins determinations of intellectual disability (n = 244). The study finds that cases in which a jury makes the intellectual dis ability determination are relatively infrequent (28 jury verdicts versus 216 judicial determinations). More striking, jury findings of intellectual disability are exceedingly rare - in fact, nationwide, there have been only three. We assess these statistics - and others - in context with: previous empirical analyses of the substantive deviations, long-standing concerns about the ability of jurors (especially death-qualified jurors) to assess mental health in criminal cases, and the risks of unreliable capital sentencing that Atkins sought to avoid.