In recent years, the U.S. Supreme Court has created two categorical exemptions to the death penalty. In Atkins v. Virginia, the Court exempted mentally retarded offenders. Three years later, in Roper v. Simmons, the Court extended the protection to juveniles. Based on these cases, the practices of foreign countries, and the opinions of professional organizations with relevant expertise, legal scholars speculate that the Court may, in the future, categorically exclude severely mentally ill offenders from the death penalty. This Note examines the feasibility of such an exemption for the mentally ill and considers its possible repercussions.