106 Iowa L. Rev. 1 (2020)
Bright line constitutional rules tend to create unfair outcomes in close proximity to the bright line. In the context of the death penalty, such distinctions possess an entirely different level of seriousness that requires deeper reflection. This Article develops the concept of presumptive penumbras around capital constitutional bright lines and argues for its application to juvenile offenders under the Eighth Amendment. Specifically, the Article advocates, within the current constitutional rules, for a presumption against the imposition of the death penalty or juvenile life without parole in cases where the age of the offender is in proximity to—within the penumbra of—the bright line of age 18.
Part II of the Article explains the inherent problems that stem from bright line rules and how both the Constitution and the death penalty exacerbate such problems. In Part III, the Article advances a typology of “presumptive penumbras”—a tool for minimizing the problems identified in Part II. Then, in Part IV, the Article applies the concept of presumptive penumbras to bright line rules related to juvenile offenders under the Eighth Amendment. Finally, in Part V, the Article concludes by sketching out some additional potential applications of presumptive penumbras to other criminal law bright lines under the Eighth Amendment.