Commonwealth v. Mattis
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In the case before the Supreme Judicial Court of Massachusetts, the defendant, Sheldon Mattis, was convicted of first degree murder among other charges, and was sentenced to a mandatory term of life in prison without the possibility of parole. At the time of the murder, Mattis was eighteen years old. He appealed his sentence, arguing that it was unconstitutional as applied to him because he was an "emerging adult" (defined in this case as eighteen, nineteen, or twenty years old at the time of the crime), and should be entitled to the same protection as juvenile offenders, who receive a term of life with the possibility of parole.
The court considered whether their previous ruling in Diatchenko I, which concluded that sentencing a juvenile to life without parole in any circumstance would violate the Massachusetts Declaration of Rights, should be extended to apply to emerging adults. The court reviewed scientific evidence showing that the brains of emerging adults are not fully mature and are similar to those of juveniles, and also considered the treatment of emerging adults in Massachusetts and elsewhere.
The court concluded that a sentence of life without the possibility of parole for emerging adult offenders violates the Massachusetts Declaration of Rights. As a result, the court invalidated the provisions of Massachusetts law that deny the possibility of parole to emerging adults. The court remanded the matter to the lower court for resentencing consistent with the court's opinion. The court also noted that this ruling does not suggest that emerging adults receiving the benefit of resentencing should be paroled once they have served a statutorily designated portion of their sentences. Instead, the parole board should evaluate the circumstances surrounding the commission of the crime, including the age of the offender, together with all relevant information pertaining to the offender's character and actions during the intervening years since conviction.
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