A state penitentiary in Chino, Calif., is training felons, while incarcerated, for high-paying jobs that will deter them from returning to a life of crime—and a jail cell.

On a hot September day in Southern California, a convicted felon clad in a heavy helmet and scuba gear dives to the bottom of a deep-water tank. He spends several minutes down there, removing bolts from large metal pipes, and communicating his progress through a radio to a dive tender and fellow inmates of the California Institution for Men, a state prison in Chino.

Fifteen minutes elapse before the man, William Jones, emerges from the tank. This is a much different scenario from a decade ago, when Jones made his living through armed robbery. Jones wasn’t caught until he intercepted a small-business owner about to make a bank deposit, and was charged with a felony. “I wanted to conquer the world one robbery at a time,” says Jones, 30, who is from Los Angeles’ Crenshaw District. “My priorities were all mixed up. I had no plan for myself, for my family, and didn’t care about anything.”

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Now, Jones is a student at the Marine Technology Training Center, a state-run program that has turned felons into divers, welders, riggers, construction supervisors and mechanics. The program has succeeded in doing something the state’s department of rehabilitation as a whole has failed at quite miserably: consistently rehabilitating criminals. The state’s recidivism rate — the percentage of individuals released from prison who are incarcerated again within three years — is an alarming 63.7 percent (PDF). The dive program’s rate, by contrast, is less than 15 percent.

The diving center achieves its low recidivism rate by offering felons a skill set that leads to a more lucrative career path than many were capable of before they were convicted. Inmates usually have little knowledge of diving or the program itself when they apply, but they’re attracted to the school because they want a way to build a better life once they’re released. Average pay in the industry is around $15 an hour at entry level, and annual salaries can climb to $100,000 within four years. That drastically reduces temptations to return to a criminal life. Perhaps more important, the program’s physical training and camaraderie give criminals a platform to build character, discipline and a sense of self-worth that turns them away from their former, illegal pursuits.

Of course, employers can be uneasy about hiring ex-felons. They carefully vet divers from the prison, and are particularly dubious of inmates-turned-divers who have a history of drug addiction. Still, the Chino graduates are known throughout the commercial diving industry for producing quality work. “The individual that I have working for me is hands down one of the best, most highly motivated guys I have on board,” says Bryan Nicholls, president of U.S. Underwater Services, a commercial diving company in Mansfield, Texas.

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Richard Barta, the owner of Muldoon Marine Services in Long Beach, Calif., agrees. “If a person comes to you and he’s turned his life around and he really wants to make something of himself, you have to look at all the positives,” Barta says.

The dive school is open to any convicted felon in a Level 1 prison facility, a low-security area where less dangerous offenders are housed. If an inmate in a higher-security facility wants to apply, he can demonstrate good behavior over time and earn his way to Level 1. Inmates who apply must have at least 18 months of their term remaining and no more than three years left.

The benefits of such a program to society are numerous. First, it saves the state money. The average prison inmate costs around $47,000 a year to incarcerate, and that’s an expense the state can avoid by investing in true rehabilitation that keeps people out of prisons. The dive program costs $9,100 per year per inmate, which is more than offset by the reduction in recidivism. Second, it boosts the economy by churning out more skilled workers who produce value. Increased oil production in the Gulf of Mexico is spurring more demand for divers who can access platforms and pipelines, says Nicholls, whose company services offshore wells in the Gulf.

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Finally, there’s the enormous social advantage of having fewer criminals on the streets. “It helps you with your morals. You have a certain pride in what you do and respect for yourself,” Jones says. “I’m a different person now. There’s no reason for me to go out there and start doing the things I was doing.”

Those benefits in Chino are even more pronounced given the pervasiveness of prison overcrowding throughout the nation. In a bid to help federal prisons that are operating at nearly 40 percent above capacity, Attorney General Eric Holder has stepped in to call for the easing of harsh sentences for low-level drug offenses. In California, overcrowding is so bad that federal judges have ordered the state to remove 9,600 inmates from its prisons. To comply, Gov. Jerry Brown authorized spending $315 million to move the inmates to private jail cells and county jails. His preferred solution, though, is a three-year extension he requested to implement mental health and drug treatment programs aimed at lowering recidivism. The judges responded by granting only a one-month extension pushing the deadline to late January 2014; if they don’t agree to a longer delay, the inmates will have to be moved. While that plan might be a stopgap, it doesn’t solve California’s chronic problem of producing too many criminals.

But the state has rehabilitation programs that do. In addition to the diving school, some 7,000 inmates work in factories on prison grounds to produce clothing, office furniture, license plates, juice, shoes, signs, gloves, eyewear and other goods sold predominately to state entities. Participants in these programs are 26 percent less likely to reoffend and go back to prison than the average prison inmate in California. A September 2013 report released by the California Rehabilitation Oversight Board said all these programs had “proven to be effective at reducing recidivism” and recommended that the correctional department work to make them more accessible. The dive center is even more effective than these programs because it helps inmates build a valuable career.

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Yet, such efforts haven’t been very accessible. Historically, the Career Technical Education program, which operates the dive school, has received no funding from Sacramento; it was financed solely by the profits of the goods that other inmates produce in factories. Some programs have been under threat of closing because of the lack of funding—including an apprenticeship in construction for inmates at the California Institution for Women— while other programs are running at a reduced level. “We’re on a dicey edge all the time on our funding,” says Fred Johnson, the marine center’s instructor. In October 2013, state officials reached a tentative agreement for the corrections department to provide $2.6 million to the CTE. Still, funding for future years remains uncertain.

That’s a shame because Johnson and his team have figured out how to address the cause of California’s correctional problem. True, inmates have to want to change in order to be rehabilitated. The physical training is so intense that 80 percent of those who sign up for the dive school drop out in the first week. Of the 200 inmates who sign up per year, only around 20 graduate. Participants are commonly sent on 10-mile runs; workouts include a seemingly implausible number of squats, pull-ups, push-ups and dips; and the training culminates in a dreaded five-mile swim. But instructors say all inmates who pass the first week’s physical tests go on to graduate, and in so doing achieve something they thought was impossible. “The secret is we change the inmate’s way of thinking,” Johnson says. “We teach them they’re not losers; that they can be winners.”

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