Massachusetts high court rules younger adults cannot be sentenced to life without parole

The highest court in Massachusetts ruled Thursday to raise from 18 to 21 the minimum age at which a person can be sentenced to mandatory life without parole — a narrow 4-3 ruling that juvenile justice advocates are hailing as progress.

The decision came in the case of Sheldon Mattis, who was convicted of the 2011 killing of a Boston teen as part of a gang feud. Mattis was 18 at the time of the shooting and was sentenced to life without the possibility of parole.

Mattis’ attorney, Ruth Greenberg, called the release of the ruling “a very good day.”

“People who are 18 are more like people who are 17 than people who are 35. They are capable of change, and often their decisions at that young age were not entirely their own,” Greenberg said. “It is courageous and it is correct, and other courts will follow it.”