The 6-1 decision ordered an end to the state Parole Board’s oversight of an estimated 300 sex offenders — oversight that allowed the board to impose jail sentences for parole violations — in a ruling that many lawyers declared a victory for due process. But victims’ rights advocates and a state prosecutor said they fear the decision removes a critical safeguard.

The Massachusetts Supreme Judicial Court ruled Wednesday that it is unconstitutional for sex offenders who have completed their sentences to be subject to lifetime supervision by the state’s Parole Board, declaring that only judges have the authority to order additional jail time for criminal violations.


“The effect this case has is to remove that automatic hammer on offenders who refuse to confine their actions to the requirements of the law, thereby decreasing their incentive to improve themselves and become law-abiding members of society,” Plymouth District Attorney Timothy J. Cruz said in a statement. “I am disappointed with the loss of this public safety tool that was intended to protect vulnerable people and children.”



The court said the 1999 state law that created “community parole supervision for life’’ for some sex offenders unconstitutionally granted sentencing powers to the Parole Board, which is part of the executive branch of the state government, violating the separation of government powers. An offender sentenced to lifetime parole could be sent to jail for violating the terms set forth by the Parole Board, even after the offender’s original sentence is completed.

Lifetime parole “constitutes an impermissible delegation to the executive branch of the core judicial function of imposing sentences,” Justice Ralph D. Gants wrote for the majority. “A judicially imposed sentence is final and may not be modified by another branch.’’

Laura M. Banwarth, a Plymouth lawyer who argued that the law was unconstitutional, said the court had no choice but to strike it down.


She noted that the SJC ruling instructs the offenders who are affected to file a motion with the courts; a prosecutor then may ask a judge to impose a new sentence. Judges have the discretion to put an offender on probation for months, years, or the rest of his of her life.

“The SJC didn’t make any new laws today,” Banwarth said. “They didn’t give any new rights to sex offenders. They just looked at the Constitution and reached the only result that they could, that sentences can only be handed down by judges.”

Supporters of the law said that it provided for strict oversight over dangerous criminals. Many of those sentenced to lifetime supervision were sometimes ordered to wear GPS devices and clear many activities, from going to the movies to buying a cellphone, with their parole officers.

But the vast majority of the 275 to 300 sex offenders currently under Parole Board lifetime oversight came under the panel’s supervision because they failed to register as a sex offender after being released from incarceration, not because they had committed another sex crime, according to those familiar with the process.

The lifetime supervision could be onerous for offenders trying to get their lives on track after being released, said Eric Tennen, an attorney who often represents sex offenders.

“It was horribly restrictive and just totally ineffective helping persons reintegrate into society,” Tennen said. Offenders on lifetime supervision could be incarcerated for 30 days for their first violation of their parole conditions, 180 days for a second violation, and one year for a third violation.


The violations could be as minor as getting caught with alcohol or leaving the state without notifying a parole officer.

The SJC ruling was made in the case of Casey L. Cole, a Level 2 sex offender who was placed on parole for life after he failed to tell police he had moved from West Bridgewater to Taunton.

He challenged the sentence, his lawyers arguing that it was unconstitutional under the doctrine of separation of government powers.

Cruz and Toni Troop, spokeswoman for Jane Doe Inc., a statewide coalition that advocates for the rights of victims of rape and domestic violence, urged the Legislature to pass an alternative law that would allow continued monitoring for sex offenders.

“Lifetime parole and supervision . . . has been a cutting-edge and critical tool in sex offender management and community safety,” Troop said.

State Senator Bruce Tarr, a Gloucester Republican, said that the Legislature would have to act fast to come up with legislation that passes constitutional muster. The legislative session is scheduled to end July 31.

“There is no question that we need to act here, because the court has taken away a serious tool for public safety,” Tarr said.



But Suffolk University Law School associate professor Chris Dearborn said the court’s decision will not create a threat to public safety. Offenders must still register with the Sex Offender Registry Board or face criminal prosecution.


“I don’t think there should be any mass hysteria that 300 really dangerous deviant people are going to go out and commit a lot of heinous acts,’’ Dearborn said.

In his dissent, Justice Robert Cordy wrote that while the law was flawed, lifetime supervision should be allowed.

“A [community parole supervision for life] sentence serves an important and central monitoring purpose, facilitating public safety by permitting and requiring intensive supervision of the sex offender population,” Cordy wrote.

Maria Cramer can be reached at mcramer@globe.com. Follow her on Twitter @GlobeMCramer. John R. Ellement can be reached at ellement@globe.com. Follow him on Twitter @JREbosglobe.