Mens Rea, Due Process, and the Supreme Court: Toward a Constitutional Doctrine of Substantive Criminal Law

Abstract

This article focuses on the common law concepts of criminal culpability as a source for a principled constitutional doctrine of substantive criminal law. The article advances the idea that the concurrence of mens rea and actus reus in the definition of crime is the very essence of due process in the Anglo-American legal tradition. As a background to a discussion of the status of mens rea and actus reus as constitutionally mandated elements of crime, the article briefly outlines the treatment of each element at common law. The article then examines the Supreme Court's treatment of each element, but will focus primarily upon the development of mens rea as a constitutional requirement. The view is advanced that in spite of earlier cases which had been thought to dispense with mens rea as a constitutional requirement, the Supreme Court has recently made clear that mens rea is an essential factor in the judicial interpretation of criminal statutes and, at least in some circumstances, in the statutory definition of crimes as well. The article also suggests that the Supreme Court's recent reliance upon the ALI Model Penal Code for a clear definition of mens rea has removed one of the major impediments to the further development of a doctrine of substantive criminal law based upon the common law notions of criminal culpability. Because of the important political implications and procedural protections which lie at the heart of this discussion, the article concludes with the suggestion that the Court's recent sensitivity to the relationship between mens rea and due process is well placed and that the continued development of a common law-based doctrine of substantive criminal law is both possible and desirable.