A ballot drive to return good time prison sentence reductions to Michigan is failing, but there’s a chance to revive the idea with a twist that could make the corrections system more effective in returning inmates to society prepared to lead productive lives.

Michigan voters ended the practice of granting time off for good behavior with their passage of a ballot proposal in 1978.

Twenty years later, then-Gov. John Engler signed a bill requiring all convicts to serve at least their minimum sentence before becoming eligible for parole.

Since then, a 10-year minimum sentence, for example, meant a convict would spend a full 10 years behind bars, regardless of how well they used their incarceration time.

The prison reform group Michigan Justice Advocacy is seeking to restore good time credits with a ballot initiative, but the effort is not taking hold. As of last month, the sponsors had gathered just 15,700 of the 356,958 signatures needed to get the proposal on the ballot.

While the petition drive will continue through the end of this month, the group acknowledged success is not likely.

That shouldn’t be the end of the sentencing reform effort.

Michigan Justice Advocacy’s proposal was perhaps too aggressive to gain broad public support. It would have cut 30 days off a sentence for every 30 days an inmate stayed out of trouble. That could have cut a minimum sentence in half.

A more palatable version is pending in the state Legislature, and the focus now should be on getting it passed.

That bill, introduced by Rep. Tyrone Carter, D-Detroit, would cut minimum sentences by up to 20% if an inmate completes skills training. Parole boards would have to agree, and the most violent convicts would not be included in the program.

The so-called productivity credits are aimed at encouraging inmates to use their time behind bars to gain skills and education that will lessen the likelihood of returning to prison.

The credits would also be a valuable prison management tool, since they provide a tangible incentive for good behavior.

Roughly 60% of the current inmate population would be eligible to earn productivity credits.

Passage of the bill would be an important signal that Michigan views its corrections system as more than a vehicle for punishing wrongdoers.

An equal priority should be rehabilitating prisoners and giving them the skills and confidence they need to lead a productive life after their release.

The reality is that most of those who go to prison will return home someday. It is in society’s interest to assure that when they do come back to their communities, they are prepared to be law-abiding citizens.

The additional benefit of moving rehabilitated inmates out of prison early is the savings to taxpayers. It costs $48,000 a year to house an inmate in a Michigan facility. The state has about 32,000 people in its state prisons.

Lawmakers should adopt the productivity credits law. Savings that come with enacting an early release policy should be poured into assuring all prisons have robust training programs.

It makes no sense to promise incentives for participating in activities that don’t exist.

Michigan should offer prisoners the incentive to not just behave themselves behind bars, but to also improve themselves.