Developmental and Neuroscientific Perspectives


A large body of developmental and neuroscientific data now lends conclusive support to the intuitions about childhood and adolescence that led to the development of the youth court system.1 Three aspects of development illustrate not only important differences between young people and adults, but also that these differences contribute to the increased level of risk-taking, including delinquency and criminal activity, in adolescence:

  • Immaturity: Individuals as young as 16 and 17 show well-developed reasoning and information-processing abilities. However, other developmental hallmarks of adolescence impair the use of these capacities in real-world decision-making, especially with regard to snap judgments, such as those made on the street or in social situations. Compared to adults, adolescents: act more on their impulses; tend not to fully anticipate the consequences of their actions; show much greater vulnerability to peer influence; and focus relatively more on the potential rewards of a risky decision and relatively less on the potential costs.

  • Vulnerability: Minors exist within myriad social systems beyond their control, including families, schools, and neighborhoods, and due to their legal status, they lack the options at the disposal of adults to change these situations or remove themselves from them. In some communities, certain levels of criminality represent a norm for behavior, not the exception. For adolescents in such areas, resisting peer pressure to commit crime can mean facing social isolation and serious risks to their physical safety.2

  • Changeability: Adolescence represents a period of character and identity formation, with individuals in this stage of life engaging in a range of behavior uncharacteristic of adulthood. Self-report studies indicate that the vast majority of adolescent boys engage in antisocial behavior that rises to the level of criminality; these behaviors, for a majority of individuals, subside as they reach adulthood.3 Though some individuals who commit crimes as a minor will turn into lifelong, career criminals, for most adolescents, legal transgressions represent a corollary of character formation and provide no window into their future, adult conduct.

Taken together, these characteristics of adolescence—the period of life during which criminal activity spikes, across individuals—strongly mitigate adolescents’ criminal culpability.

In addition, research on the structure and function of the adolescent brain, and changes occurring in it, are consistent with described developmental findings:

  • Frontal Lobes: The brain’s frontal lobes, and especially the prefrontal cortex, play a central and critical role in “executive functions.” This category of cognition includes planning, decision-making, assessing risks, and evaluating potential consequences. The prefrontal cortex also is important in emotion regulation and impulse control. Brain imaging reveals that adolescents lack a fully mature pre-frontal cortex.

  • Myelination: Myelination refers to a process in which the fatty tissue, myelin, forms around neuronal projections. The presence of myelin improves the speed and reliability of signals passing between neurons. In adolescence and young adulthood, significant myelination occurs within the prefrontal cortex, subcortical brain structures implicated in emotional processing, and the neuronal pathways between them.

  • Synaptic Pruning: Synaptic pruning describes a process in which unused synapses, or connections, between brain cells are eliminated. This improves information processing, by allowing signals to take the most efficient neural pathways. The adolescent prefrontal cortex undergoes significantly more synaptic pruning than other brain structures.

The myelination and synaptic pruning that occur throughout adolescence make considerable changes to the frontal lobes and their connections to subcortical brain structures. As these processes unfold, the “executive functions,” including impulse control and risk evaluation, improve. However, these changes occur over an extended period of time during adolescence, even into young adulthood, and these findings support the developmental view of adolescence as a time marked by “behavioral and psychosocial immaturity.”

Policy Implications

The science regarding adolescence urges the adoption of responses to juvenile crime that are: applied, to the maximum extent possible, within the community; developmentally appropriate, while still holding young offenders accountable for their actions; and aligned with what research shows to be effective.

Unless a young person represents a risk to the safety of the community, it provides maximum benefits to the individual and society to keep them out of secure facilities. Conditions within these settings pose health and safety hazards, and incarceration is expensive and increases the likelihood of recidivism and subsequent incarceration.4 5 Alternately, applying sanctions and providing rehabilitation in the community helps to realize healthy developmental outcomes, including the decrease in criminal behavior that corresponds with the emergence of adulthood.6

Whether in the community or in a secure facility, though, recent research bears out certain common principles of effectiveness for intervention with juvenile delinquents. Such programs provide social supports and a consistent authority presence, seek to develop individuals’ skills and decrease antisocial behaviors, and aim to strengthen families.

Reauthorization of the Juvenile Justice and Delinquency Prevention Act must account for the developmental perspective and foster alternatives to incarceration and supports for individuals returning to the community from secure facilities. Such a perspective does not seek to excuse criminal behavior. However, it recognizes that supporting the healthy development of young people in the juvenile justice system greatly increases the chances that these individuals will find stable jobs, pay taxes, and contribute to the community in additional, meaningful ways.


1 Except as noted, this background section is based on statements made by APA in amicus briefs that detailed the relevant developmental and neuroscientific findings in the U.S. Supreme Court Cases of Roper v. Simmons and Graham/Sullivan v. Florida.

2 Scott, E. S. & Steinberg, L., (2008). Adolescent Development and the Regulation of Youth Crime. The Future of Children, 18(2), 15-33.

3 Moffitt, T. E., (1993). Adolescence-Limited and Life-Course-Persistent Antisocial Behavior: A Developmental Taxonomy. Psychological Review, 100, 674-701.

4 Mohr, H., (2008). 13K Claims of Abuse in Juvenile Detention Since ’04. Associated Press. Retrieved from

5 Scott, E. S. & Steinberg, L., (2008). Adolescent Development and the Regulation of Youth Crime. The Future of Children, 18(2), 15-33.

6 Ibid.

7 Ibid.