In a ruling today (in Commonwealth v. Mattis), the Massachusetts supreme court held by a 4-to-3 vote that murderers who are “emerging adults, that is, those who were eighteen, nineteen, and twenty years of age when they committed the crime,” have a right under the state constitution’s ban on “cruel or unusual punishments” not to be sentenced to mandatory life imprisonment without the possibility of parole. Chief justice Kimberly Budd’s majority opinion relied heavily on “[a]dvancements in scientific research [that] have confirmed what many well know through experience: the brains of emerging adults are not fully mature.” She therefore extended to them the same protection that her court had previously extended to juvenile offenders aged fourteen to seventeen.
Here is an excerpt from Justice David Lowy’s dissent, which Justice Elspeth Cypher and Justice Serge Georges Jr. joined:
Contrary to the court’s conclusion …, the objective sources of contemporary standards of decency in the Commonwealth simply do not reflect a public consensus that life without parole, when imposed mandatorily on individuals from eighteen to twenty who have been convicted of murder in the first degree, is cruel or unusual. Rather, the Legislature has definitively drawn the line between childhood and adulthood at eighteen, and objective indicia of contemporary standards of decency in the Commonwealth demonstrate support for, rather than objection to, treating individuals within this age range as adults in our criminal justice system when they commit the crime of murder in the first degree….
[S]cientific brain research, untethered to societal views expressed through legislation, can neither draw the line between childhood and adulthood nor manufacture a new category of individuals entitled to distinct constitutional treatment for purposes of determining whether a sentence is constitutionally disproportionate under art. 26. And, even if it could, science does not definitively place the line of brain maturation at twenty-one, but rather suggests that it extends into the mid-twenties. Perhaps nothing speaks louder to the flaws in the court’s holding that this mandatory sentence violates art. 26 than the court having crafted a line that ends at age twenty-one, thereby engaging in legislative line drawing inconsistent with the science upon which it relies. Where punishment is involved, we must look to society and the Legislature to determine where the appropriate line is and where it should be.
In her own dissent, Justice Cypher observes that a “significant amount of time and energy has been expended to prove through science what the Legislature knew when it promulgated its first statute concerning juveniles: young males take more risks and are more impulsive than older males.” Among her many points, Cypher notes that the majority’s reasoning “dispenses with any expectation that our legal norms can influence the development of juveniles” and emerging adults.