Juvenile offenders are treated harshly in that they receive adult-like punishment and are incarcerated when alternatives to incarceration are possible. Research on adolescent offenders suggests that they are less mature than their adult counterparts and that they suffer psychosocial setbacks as a result of incarceration. We examined the effect of psychosocial immaturity information on culpability judgments about juvenile offenders. In Study 1, we provided information about limitations in adolescents’ abilities to control their impulses, weigh risks and benefits, and consider the future consequences of their behavior. Compared with a control condition, those in the immaturity conditions attributed less responsibility to the offender. In Study 2, we manipulated both immaturity information and an actor’s mental state beliefs about the consequences of his action. We found that mental beliefs weighed more heavily in judgments about responsibility and guilt than information about immaturity. Discussion focuses on implications of this research for juvenile justice.