Toward a new test for the insanity defense: Incorporating the discoveries of neuroscience into moral and legal theories

Lawbreakers whose cognitive abilities appear unimpaired sometimes commit crimes despite knowing or appreciating the wrongfulness of their actions. Traditional theorists have argued that these individuals deliberately chose to act criminally and should be punished accordingly. Recently, findings from the empirical sciences, however, suggest that in a subset of these offenders, the emotional and biological cues that normally guide behavior are absent, thus depriving the affected individuals of the capability for rational choice and-by extension-moral agency. In these cases, criminal punishment is unwarranted. In this Comment, Laura Reider draws upon discoveries in the field of neucroscience to challenge the assumptions underlying current versions of the insanity defense. She argues that offenders with sufficiently impaired emotional systems should not be held responsible as moral agents in the criminal justice system. Toward that end, this Comment traces the evolution of the insanity defense and criticizes its various formulations in light of data from the brain sciences. In conclusion, this Comment articulates a broader version of the insanity defense, one that is consonant with the human capacity for rational behavior as measured in scientific terms, and then assesses its ramifications.