SACRAMENTO, Calif. — Gov. Jerry Brown dramatically altered California’s criminal sentencing system when he was first governor a generation ago.

Now he is asking voters to partly change it back by giving corrections officials more say in when criminals are released and stripping prosecutors of the power to decide when juveniles should be tried as adults. He says both would help rein in a legal code that he believes has tilted too far in favor of get-tough policies.

His Proposition 57 on the Nov. 8 ballot alarms many law enforcement officials, coming after a jump in crime last year and major policy shifts in the last five years that have put California on the national forefront of reducing mass incarceration.

The state shifted responsibility for many felons from state prisons to county jails in 2011 to reduce prison overcrowding. Voters have supported reducing criminal penalties twice since then, revising California’s career criminal “three strikes” law in 2012 and lowering penalties for certain drug and property crimes in 2014.

The Democratic governor argues his initiative is needed to keep the inmate population below the cap set by federal judges. He also wants to fix what he sees as a festering problem as he enters the final two years of his record tenure.

“One of the beauties of being in government over a 42-year period: You get to make mistakes that you then get to correct,” Brown told the California Chamber of Commerce in May.

Brown signed the state’s current sentencing law in 1977, letting judges instead of parole boards determine when most convicts should be released.

“I thought things were too uncertain and we need clear, certain punishment,” he said.

But he argues lawmakers have since overreacted by passing too many criminal laws along with 400 sentencing enhancements for things like using a gun or being involved in a gang while committing the underlying crime.

Proposition 57 would restore some of that earlier flexibility by allowing “nonviolent” inmates to seek parole hearings. Under California law, however, that would exclude only those convicted of fewer than two dozen crimes like murder and kidnapping.

It would also allow parole consideration after inmates complete the prison term for their primary offense, but before they serve any additional sentence connected to other crimes or enhancements. Many inmates have longer sentences for the enhancements, including life prison terms, than for the underlying crime.

It also would give the Department of Corrections and Rehabilitation broad authority to give earlier release credits to inmates, including those convicted of violent crimes, who complete classes or treatment, if the corrections secretary certifies that they “protect and enhance public safety.”

It would substitute state officials’ opinions for judges’ more informed and timely consideration of how long criminals should spend behind bars, said Ventura County District Attorney Greg Totten, speaking on behalf of the California District Attorneys Association that opposes the initiative.

“That judge’s decision could be completely ignored by a state bureaucrat and they could mete out any sentence they want to,” Totten said.

The initiative would give inmates incentives to behave and better themselves in prison in hopes of earning an earlier parole, said Amador County Chief Probation Officer Mark Bonini, president of Chief Probation Officers of California that supports the measure.

“Ultimately maybe we’ve built a better person and we’ve given them some skills that they can put to advantage on the outside and maybe engage in a positive way,” Bonini said.

The nonpartisan Legislative Analyst’s Office projects about a quarter of California’s nearly 130,000 prison inmates could seek parole if it passes.

It’s a truncated version of the usual parole process: A state employee does an administrative review to determine if the inmate’s release would pose an unreasonable risk to public safety. Inmates, prosecutors and victims may send written comments. But there are no hours-long hearings to weigh testimony from inmates, their attorneys, victims and prosecutors, and the governor has no role in allowing or blocking the inmate’s release.

The initiative would also reverse voters’ decision in 2000 to make California one of 15 states that that lets prosecutors decide if juveniles as young as 14 should be tried in adult court, instead requiring judges’ consent before any youth could be tried in adult court.

Associated Press writer Alison Noon contributed to this story.