Major advances in neuroscience since the 1990s helped convince the Supreme Court to rein in how we punish young killers.
Hundreds of Americans convicted of homicide as kids have a shot at freedom after last week's Supreme Court ruling Montgomery v. Alabama, which centered on 69-year-old Henry Montgomery killing an East Baton Rouge, Louisiana, police officer while he was skipping school in 1963.
As the New York Times reported, the decision basically requires retroactive enforcement of a 2012 Supreme Court decision, Miller v. Alabama, that banned mandatory sentences of life without parole for juvenile killers. Taken together, the rulings mark a dramatic shift in how America punishes young people convicted of violent crimes. But these changes didn't emerge solely from decade-long court fights.
In fact, they began in the laboratory.
In the 1990s, advances in neuroscience allowed experts to study and map the adolescent brain in ways they never had. As Justice Anthony Kennedy wrote for the majority in Roper v. Simmons, a 2005 decision that banned the death penalty for juveniles, studies were confirming what "any parent knows": Adolescents are, in fact, serial risk-takers who often give into peer pressure.
Or, to put it more scientifically, adolescents are "environmental sponges," says Dr. Judith Edersheim, co-founder and co-director of the Center for Law, Brain and Behavior at Harvard Medical School. Edersheim says the neurological studies began showing what psychological studies had indicated for decades: Children, and even young adults, are a product of their environments.
"Adolescence is a period of time when the brain is hyper plastic. It's a period of rapidly-changing brain," she says. "Adolescents are supposed to take risks. That's what their neurotransmitters and their brains are telling them. But they calculate risks differently from grown ups, and it has an evolutionary purpose and a neurological basis."
According to Edersheim, the adolescent brain undergoes a period of "pruning" before adulthood. So it's not that teens just turn into crazy people—rather, their brains begin to learn to "process efficiently." And to do that, they need to take cues from their surroundings.
The neuroscience, she says, debunked the myth of the young "superpredator" that preceded it. Buoyed by sensational cases like that of a Somerville, Massachusetts teen who stabbed his friend's mom to death over 90 times, experts in the 1990s predicted the era's troubled children would grow up to wreak havoc on society. Princeton Professor John DiIulio suggested in 1995 that there would be up to 270,000 "young predators" in the street by 2010, and criminologist James Alan Fox famously warned law enforcement, "Unless we act today, we're going to have a bloodbath when these kids grow up." (Both later conceded the trend was not borne out.)
While the latest high court ruling leaves room for judges to sentence juveniles convicted of murder to life without parole if they are deemed beyond saving, Edersheim argues "the new neuroscience of adolescent brain development is what makes 'incorrigibility' vanishingly rare." In other words, she believes the science shows that most juveniles can, in fact, be rehabilitated—even if the crime they committed is especially gruesome.
Laurence Steinberg, a professor of psychology at Temple University, was the lead scientist in all three of the American Psychology Association (APA) amicus briefs used in various Supreme Court rulings over the last decade reining in how we punish young killers. Each brief summarizes dozens of studies in the field of juvenile psychology and neuroscience.
"Rather than point to one specific study, we basically said, 'Look, there has been an accumulation of evidence showing that brain maturation, especially in regions that regulate self control, is still ongoing in late adolescence and maybe into early adulthood,'" Steinberg says.
Though psychological differences between adolescents and juveniles had been presented to the court in the past, Roper v Simmons was first big case where neurological data seemed to play a starring role.
Steinberg describes these findings in neuroscience as an "identifiable biological basis for the kind of common-sense observation that kids have more difficulty controlling their impulses and thinking ahead and resisting peer influence than adults do."
According to Steinberg, what was so revolutionary about these studies wasn't the conclusion that young people are impulsive and easily coerced into peer pressure. It was that for the first time, the Supreme Court took the research seriously.
"It took brain science to have people finally accept that," he said.
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