Outside the Box: Courts have ruled that sentencing kids to die in prison is cruel and unusual. Now they’re reconsidering when adulthood starts. 

The judge who sentenced them, though, couldn’t consider the scope of Mattis’s role in the crime or what led him to become entangled in gang violence. She was allowed to consider nothing beyond the worst moment of Matttis’s life. While Watt, 17 at the time of the crime, would be eligible for parole after 15 years, because Mattis was almost 10 months older and thus a legal adult, he automatically received a sentence of life without possibility of parole. 

Now, though, Mattis will attempt to convince a judge that he, too, should get a parole hearing one day. Recently a Massachusetts Superior Court overturned his sentence, ruling that people cannot be automatically sentenced to die in prison for crimes they committed before age 21. 

Massachusetts is not alone. Just a week after its Superior Court released its decision, Michigan’s highest court took a step in the same direction, banning automatic life-without-parole sentences for 18-year-olds. And last year, the Washington State Supreme Court banned mandatory life-without-parole sentences for people younger than 21, observing that “modern social science, our precedent, and a long history of arbitrary line drawing have all shown that no clear line exists between childhood and adulthood.”

These decisions build on a series of U.S. Supreme Court opinions over the past two decades recognizing that adolescents are less-equipped to control their impulses, possess heightened capacity for rehabilitation, and thus cannot be constitutionally subject to the most severe sentences, including the death penalty and mandatory life-without-parole. However, these cases draw a firm line at age 18, allowing those even a day older to be sentenced as adults. 

‘Emerging adults’

Because individuals are most likely to commit crimes during young adulthood, the legal system’s ruthless treatment of this age group is a major driver of mass incarceration, swelling state prison populations and driving exorbitant spending. Increases in sentence length, rather than increases in crime, were responsible for half of the astronomic growth in overall incarceration rates between 1980 and 2010, and now, 40% of people serving the longest prison terms were incarcerated before age 25. With the U.S. now spending upwards of $81 billion on incarceration each year, the legal system’s decision to maintain a bright line of adulthood at age 18 has come with staggering costs. 

A slew of evidence has shown that many of the Court’s reasons for treating minors differently apply equally to “emerging adults” in their late teens and early-to-mid twenties. While they’re clearly not kids, young-adults’ brains continue developing until at least their mid-twenties, in ways that make them more impulsive, prone to underestimating risk, and susceptible to peer pressure, much like their younger peers. 

Importantly, development during emerging adulthood is profoundly influenced by context. Young adults are less-equipped to handle stress than older adults and have less, if any, control over factors that lead to long-term, extreme stress, such as housing instability, volatile family relationships, and exposure to abuse.

In stable circumstances, they may be able to function like adults, but in emotionally charged-situations, they are more likely to slide into impulsive, risk-taking behaviors typical of adolescence. By ignoring these factors when sentencing emerging adults, courts inevitably compound the structural racism and poverty that expose some to high rates of stress and trauma. 

Emerging adults also differ from older adults in their heightened capacity for rehabilitation. While individuals of all ages possess significant potential for evolution and growth, that potential is even greater while the brain is still developing. That’s part of the reason why crime rates drastically drop off after age 25; as brains mature and develop new ways to process trauma, it is common for people who were once young and violent to build stable, productive adult lives. It’s also part of why people who have been released early after receiving extreme sentences as youth have shown remarkably low recidivism rates. 

This growing research base is starting to spark small changes in the criminal legal system’s treatment of emerging adults. In addition to the Washington and Massachusetts court decisions, a few states have carved out special sentencing procedures for young people over 18 and a couple have even guaranteed sentencing review hearings to people given extreme sentences for crimes they committed before age 25.  

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