Skip to content 
Systems involved in emotional responses, rewards, and social sensitivity undergo important changes during adolescence.
Meanwhile, the neural networks involved in self-regulation, planning, and cognitive control continue maturing into early adulthood.
The prefrontal cortex plays an important role in several of these processes.
It contributes to judgment, impulse regulation, working memory, and the ability to compare possible consequences before making a decision.
During adolescence, these abilities are still developing.
This helps explain why teenagers may sometimes understand that an action is dangerous while nevertheless taking the risk.
A young person might recognize that participating in a reckless confrontation could have serious consequences but still respond impulsively when frightened, angry, embarrassed, or pressured by friends.
The National Academies’ research on juvenile justice emphasizes that adolescent behavior emerges through an interaction between neurological development and the surrounding social environment.
nationalacademies.org
Family relationships, schools, neighborhood conditions, friendships, and exposure to violence can all influence behavior.
No single brain region or developmental milestone can explain why an individual commits a crime.
It is also inaccurate to suggest that every person’s brain suddenly becomes fully mature at age 25.
Development is gradual, varies between individuals, and depends on the psychological ability being examined.
Nevertheless, the broader scientific evidence supports an important conclusion: adolescents and adults should not automatically be treated as developmentally identical when courts determine punishment.
Impulsivity and the Influence of Peers
Peer influence is particularly important during adolescence.
Teenagers often place considerable value on social acceptance, belonging, and reputation.
In some circumstances, these pressures may encourage positive behavior, such as academic achievement or participation in community activities.
In other situations, they can contribute to reckless decisions.
Imagine a teenager surrounded by friends who encourage a dangerous prank.
The teenager may understand that the behavior is wrong but worry more immediately about appearing weak or being rejected.
The potential social consequences may feel more urgent than the distant possibility of legal punishment.
This does not eliminate responsibility.
It does, however, help explain why a young person’s decision-making process may differ from that of a mature adult.
The same developmental flexibility that creates vulnerabilities can also provide opportunities for meaningful improvement.
With appropriate guidance, education, treatment, and stability, adolescents can develop stronger emotional regulation and decision-making skills.
That capacity for change is one of the foundations of modern juvenile rehabilitation.
Why the Supreme Court Changed Its Approach
The United States Supreme Court has played a major role in redefining the constitutional limits of extreme sentences imposed on people who committed crimes before turning 18.
Over roughly two decades, a series of landmark decisions established that youth matters when courts determine the most severe punishments.
These rulings did not eliminate serious penalties for violent juvenile offenses.
Instead, they recognized that childhood and adolescence can affect legal culpability and that certain punishments violate the Eighth Amendment’s prohibition against cruel and unusual punishment.
2005: Roper v. Simmons
In 2005, the Supreme Court ruled that individuals cannot be executed for crimes committed before their eighteenth birthday.
The decision reflected several important considerations.
Young people generally possess less mature judgment than adults, may be more vulnerable to external pressures, and have a greater possibility of personality development.
The Court concluded that these differences made the death penalty unconstitutional for juvenile offenders.
The ruling did not mean that serious juvenile crimes should go unpunished.
It established that the death penalty was an unacceptable punishment for crimes committed by minors.
2010: Graham v. Florida
Five years later, the Supreme Court addressed juvenile life imprisonment without the possibility of parole.
In Graham v. Florida, the Court ruled that a person who committed a non-homicide offense before turning 18 could not be sentenced to life without parole.
The decision recognized that even a serious non-homicide offense should not automatically eliminate every meaningful opportunity for eventual release.
Importantly, this did not guarantee freedom.
A person could still serve a lengthy prison sentence.
The constitutional requirement concerned the availability of a meaningful opportunity to demonstrate maturity and rehabilitation.
2012: Miller v. Alabama
The Court went further in 2012.
In Miller v. Alabama, it held that mandatory life-without-parole sentences for juvenile homicide offenders were unconstitutional.
A mandatory sentence leaves a judge no discretion to consider the individual defendant’s circumstances.
Under such a system, two teenagers convicted under the same law might receive identical life sentences despite significant differences in age, maturity, family background, participation in the crime, or potential for rehabilitation.
The Court determined that sentencing procedures must allow consideration of youth before the harshest available punishment is imposed.
2016: Montgomery v. Louisiana
In 2016, the Supreme Court clarified that the constitutional rule established in Miller applied retroactively.
This meant that individuals who had already received mandatory juvenile life-without-parole sentences could potentially seek relief.
For some, the ruling created the possibility of resentencing or parole consideration after decades in prison.
It did not automatically release everyone affected.
Courts and states still needed to determine how to implement the constitutional protections.
2021: Jones v. Mississippi
The legal landscape became more complicated in 2021.
In Jones v. Mississippi, the Supreme Court held that a sentencing judge was not constitutionally required to make a separate factual finding that a juvenile was permanently incapable of rehabilitation before imposing life without parole.
The ruling preserved the prohibition against mandatory juvenile life-without-parole sentencing while allowing discretionary sentences in circumstances where state law permits them.
Together, these five decisions demonstrate the tension between recognizing adolescent development and preserving judicial authority to impose severe penalties for grave offenses.
The Sentencing Project+1
Why Juvenile Life Without Parole Remains Controversial
Juvenile life without parole, often abbreviated as JLWOP, means that a person who committed an offense before age 18 receives a life sentence without an ordinary opportunity for parole.
The punishment is among the most severe available within the American criminal justice system.
For someone sentenced at 16 or 17, it may mean living for many decades in prison with no scheduled opportunity to demonstrate rehabilitation.
Supporters of permitting such sentences argue that certain crimes are so serious that permanent confinement may be warranted.
They emphasize the gravity of homicide, the rights of victims, and the government’s responsibility to protect the public.
They may also argue that judges should retain discretion to impose the harshest punishment in exceptional circumstances.
Opponents argue that a sentence permanently eliminating the possibility of release is particularly difficult to justify for someone whose crime occurred during adolescence.
They contend that no court can reliably know whether a teenager will remain dangerous or incapable of reform throughout an entire lifetime.
The debate therefore involves two different forms of uncertainty.
One concerns the seriousness of the harm already caused.
The other concerns the person the offender may become decades later.
Neither question can be answered solely by examining age or the crime’s legal classification.
How Different States Handle Juvenile Sentencing
American juvenile sentencing laws are not uniform.
States differ in how they treat young defendants, when they permit prosecution in adult court, and whether people convicted of serious juvenile offenses can eventually become eligible for parole.
According to the National Conference of State Legislatures, 28 states and Washington, D.C., have eliminated juvenile life without parole through legislation or judicial rulings.