The Mentally Disordered Criminal Defendant at the Supreme Court: A Decade in Review

In the past decade, at least eight cases involving issues at the intersection of criminal law and clinical psychology have reached the United States Supreme Court. Of particular interest are those cases which concern three general topics: the culpability of juvenile offenders; mental states and the criminal process, including the presentation of mental disorder evidence, competency to stand trial, and competency to be executed; and the preventive detention of convicted sex offenders. Of these eight cases, two cases cases adopted categorical exclusions from certain kinds of punishment, three involved questions about mental states (and in two of these the Court misunderstood the relevant psychology), and two cases involved the question of whether the preventive detention of convicted sex offenders is really civil commitment, or is instead criminal punishment. Among the issues raised in these cases are the legal primacy of diagnoses recognized by psychiatrists, and the moral justification for the civil commitment of people who are dangerous because of a mental disorder. The trial of a criminal defendant, the determination of criminal responsibility, and the imposition of a death penalty all require the assessment of mental states. Culpability is at least partly a function of such mental states as awareness, understanding, and intention. Society considers those who deliberately cause harm to be more blameworthy than those who unintentionally cause harm. Mental states thus define the dividing line between civil commitment and criminal punishment, as well as degrees of general criminal culpability. In the last decade, the Supreme Court decided cases that involved all of these issues of clinical psychology, and is willing, if not eager, to decide more. It is therefore imperative to evaluate the Court’s ability to consult psychology appropriately when answering criminal law questions, for this ability is critical to the integrity of both law and psychology