Kahler v. Kansas: The Constitutionality of Abolishing the Insanity Defense

The U.S. Supreme Court has not previously ruled on whether the insanity defense, a long-established component of criminal law, is constitutionally required. Five states have abolished the insanity defense, and a challenge to one of those laws reached the court last year. In sharply contrasting opinions, the justices differed on whether the insanity defense is so rooted in Anglo-American jurisprudence as to be deemed fundamental, with the majority finding it not required by the Constitution. Although the decision is unlikely to lead to immediate changes in state laws, it illuminates the Supreme Court’s views on the moral basis for criminal punishment.