This week’s state Supreme Judicial Court decision, striking down a law allowing teenagers convicted of murder to be sentenced to life in prison with no possibility of parole, is in keeping with recent U.S. Supreme Court decisions and scientific opinion on the mental development of juveniles. The ramifications will have to be addressed by the state Parole Board, which will be charged with assuring that justice is done in cases that until this week had apparently been decided for good.

The SJC asserted that it was in agreement with medical research finding that the thinking patterns of teenagers are less developed than adults, which means by extension that treating them as adults and depriving them of parole constitutes cruel and unusual punishment. The U.S. Supreme Court and several states have reached the same conclusion. The SJC found that teenagers convicted of murder should be eligible for parole 15 years after their convictions, which is the same as an adult convicted of second-degree murder.

The ruling will immediately affect about 60 cases, including that of Edward S. O’Brien, who in 1995 stabbed Janet Downing, a neighbor in Somerville, more than 90 times. That case and several other brutal crimes committed by teenagers persuaded the Legislature to pass extremely harsh laws against juvenile offenders convicted of murder and there has not been a public outcry to have them repealed.

The Parole Board will now have to come up with a strategy to address the SJC decision, and in doing so, it must consider the understandable unhappiness of families of murder victims who thought the guilty were in jail for good. Now, they will confront the murderers again at parole hearings and face the prospect of their freedom. Parole is never automatic, but in these cases it should involve the clearing of an extremely high bar.