Massachusetts can lock the door behind the inmates housed in its prisons, but Harold Clarke says that more than 90 percent of the time the state can’t throw away the key.

So his top priority as the new chief of the Massachusetts prison system is to make sure the vast majority of inmates who are eventually released get the mental health and substance abuse counseling, education and job training programs they need to stay out of prison.

Some call that lenient, Clarke says it’s good sense.

“If they go back home having left environments that were just punitive, they’re going to take out their anger and rage on the citizens once they get back out into the community,” he told The Associated Press in an interview in his office.

Clarke, a 56-year-old who grew up in Panama and has run state prison systems in Nebraska and Washington state, says reducing recidivism is his top goal and the reason Gov. Deval Patrick hired him last month to take over Massachusetts’ prisons.

Patrick, a former civil rights lawyer in the Clinton administration, advocates for reforms of mandatory minimum sentences and has filed legislation requiring post-release supervision and support for prisoners. He says half of the 20,000 inmates released from incarceration annually are back in jail within a year.

The Massachusetts Department of Correction has 10,000 inmates in 18 facilities — mostly prisons as well as a hospital and substance abuse center. It is a smaller operation than in Washington, D.C., where Clarke spent more than two years after working his whole career in the Nebraska prison system, rising from counselor to a 15-year stint as commissioner.

His Washington experience produced mixed results. Clarke helped develop a $30 million re-entry program that took effect this summer and is credited by many as a national model.

It requires each inmate to have a re-entry plan, ideally from the moment they are incarcerated. It authorizes two-year college degrees, financed by family, outsiders or loans. It also would link the ex-convicts with community services, coordinate tracking by the criminal justice system and impose stiffer penalties for repeat violations of probation.