STATE LEADERS UNVEILED long-awaited legislation Tuesday aimed at reducing recidivism rates in the criminal justice system. But whether the bill tackles the most pressing issue facing the system or simply marks a good first step in what should be a more sweeping reform process depends on which leader is speaking.

That divide is likely to animate what is shaping up to be the most robust debate on state criminal justice policy in many years.

The bill would allow state prisoners to earn more “good time” credits that reduce their sentence, and would provide more services and programming for offenders while incarcerated and after their release. It would also allow some of those sentenced to mandatory minimum sentences for drug crimes to earn time off their sentence by taking part in prison programs, something not allowed under current law. Those convicted of distribution of opiates or trafficking heroin, or whose drug crime involved violence or a weapon, would not be eligible.

The legislation is the product of a review commissioned in 2015 when Gov. Charlie Baker, Senate President Stan Rosenberg, House Speaker Robert DeLeo, and Supreme Judicial Court Chief Justice Ralph Gants asked the nonpartisan Council of State Governments to conduct an evidence-based evaluation of state criminal justice policies.

The review, part of the federally-funded Justice Reinvestment Initiative, which has been carried out in more than two dozen states, requires initial agreement among a state’s top leaders on the scope of the problem and a commitment to follow through with legislative and policy changes. The four leaders, who all appeared at the morning announcement, agreed on the need for reforms at the “back end” of the system aimed at lowering recidivism rates among those who have served time in prison, even if they differ on whether further major changes should also be pursued.

The state leaders heard loud and clear the view that the new legislation doesn’t go far enough as advocates interrupted the State House presentation with chants calling for repeal of mandatory minimum sentences, reform of the bail system, and other changes. “Jobs not jails,” chanted the protesters from the Massachusetts Community Action Network, an umbrella organization of faith-based and community groups.

Three-year recidivism rates for those released in 2011 were 48 percent for those exiting Massachusetts houses of correction and 38 percent for those leaving state prisons. The state’s overall incarceration rate, however, is the second lowest in the country, a fact that Baker has emphasized repeatedly throughout the process.

“By and large, people who aren’t supposed to be in the Massachusetts prison system typically are not,” Baker said at the announcement. “On the other hand, what we do have in Massachusetts is a problem with recidivism.”

While Baker views recidivism as the main area in need of attention, Rosenberg and Gants have made it clear that they think it is just one part of a broader set of issues that should be addressed, including changes to sentencing laws.

“I see this as as step in the right direction,” said Rosenberg, who is supporting an effort by a large group of Democratic senators to advance a range of further reform proposals. DeLeo has largely held back from saying whether he thinks other changes are needed.

Underscoring the divide in viewpoints, just hours after the early-morning announcement, Gants delivered a keynote address at a conference in which he declared the bill the criminal justice reform equivalent of a first down. To score a touchdown, he said, the state needs to pursue a much more comprehensive agenda that includes reform of fees and fines assessed to criminal offenders, expansion of “wraparound” services that probation and parole officers can connect offenders with, and elimination of nearly all mandatory minimum sentences.

Gants, who has previously called for elimination of mandatory minimum sentences for nonviolent drug offenders, went much farther in his address, urging repeal of mandatory minimum sentences for all crimes except murder and repeat drunken driving offenders.

“It is time to recognize that mandatory minimum sentencing is a failed experiment that must end,” Gants said at a criminal justice reform conference at Boston College Law School sponsored by the Rappaport Center for Law and Public Policy.

Suffolk District Attorney Dan Conley rips Gants for wading into ‘political arena’ to push sentencing changes

Michael O’Keefe, the Cape and Islands district attorney, who served on the 25-member working group that reviewed state policies, said calls for repeal of mandatory minimum sentences are misguided. He said the state’s low incarceration rate demonstrates the “thoughtful employment” of mandatory minimum sentences by the state’s 11 district attorneys. “Despite all of the criticism, we’re really a model for the rest of the country,” O’Keefe said following the State House announcement.

Critics of the mandatory sentencing laws, led by Gants, say they improperly tie the hands of judges and that prosecutors use the threat of mandatory minimum charges to get defendants to plead guilty to lesser charges, with the prosecutor able to set out the penalty as part of the plea deal. “Where that individual pleads out, the sentence is not really determined by the judge, it’s determined by a prosecutor,” Gants said in his speech at Boston College. “The governor has chosen very fine judges. Let us do our job in accordance with the best practices that we have established.”

Gants said the Council of State Governments review emphasized the importance of tailoring recidivism-reduction programming and services to individual offenders and that the same approach should be taken to sentencing. “We need to be able to craft individualized sentences that fit that crime and that fit that defendant,” he said.

While many critics of current practices have focused on repealing mandatory minimums for nonviolent drug offenders, Gants has upped the ante in the debate by arguing that mandatory sentences should be repealed for virtually all crimes so that judges can weigh the circumstances of each case.

He cited as an example of the problem the mandatory minimum sentence for possession of a firearm. “It does not matter whether or not you are carrying a gun because you are the enforcer for a street gang or whether or not you are frightened to death of the enforcer for the street gang — it’s the same mandatory sentence,” he said.

Sen William Brownsberger, cochairman of the Legislature’s Joint Committee on the Judiciary, said the enhanced good time credits for taking part in prison programs in the bill filed today could lead to a reduction of up to 35 percent in sentences for those in the general prison population.

The governor’s 2018 budget proposal also includes $3.5 in additional funding recommended by the Council of State Governments review to improve programming aimed at reducing recidivism among county inmates and state prisoners. Brownsberger said a focus of the added funding would be on programs shown to have the biggest impact on recidivism, “which are cognitive behavioral programming oriented towards changing criminal thinking. The best predictor of whether somebody is going to commit a crime,” he said, “is whether they think that committing a crime is OK.”

Brownsberger echoed the views of Rosenberg and Gants on the recidivism legislation. “I think it offers some positive steps forward,” he said. “I think there’s a much broader agenda to address.”

Baker seemed to recognize that the bill unveiled today will not mark the end of the criminal justice debate in the current legislative session. “We’re going to file legislation associated with this initiative, but I fully expect a bunch of those issues will come up as well,” he said of other reform proposals being advocated. “There are certainly other issues that should be addressed.”