Using Developmental Science to Distinguish Adolescents and Adults Under the Law

A developmental scientific perspective on drawing legal age boundaries begins with the premise that the age at which the rights and responsibilities of adulthood are conferred to minors must align with the psychological capacities and skills necessary to exercise good judgment in specific contexts. This article examines three aspects of development relevant to this analysis: cognitive capabilities, especially those that support reasoned and deliberative decision making; psychosocial capacities, especially those that facilitate self-regulation under conditions of social or emotional arousal; and neurobiological maturation in brain regions and systems that undergird these cognitive and psychosocial skills. We conclude that the maturation of the capacity to reason and deliberate systematically precedes, by as much as five years, the maturation of the ability to exercise self-regulation, especially in socially and emotionally arousing contexts. Legal age boundaries should distinguish between two very different decision-making contexts: those that allow for unhurried, logical reflection and those that do not.