CHICAGO (CBS) — Cook County Sheriff Tom Dart used the friendliest possible tone on Thursday to deliver the harshest possible message to inmates as he welcomed another training program to Cook County jail, this one providing guitar lessons.

“Let’s be painfully real here for a second. You being here, you are net zeroes for your family right now,” Dart told inmates. “You should be ashamed of yourself, you really should. Your children don’t have their dad to run to right now to say ‘Dad, help me out. Dad, protect me. Dad, be there for me.’”

Musician and former federal prisoner Wayne Kramer of MC5 donated 10 guitars so inmates can take lessons.

Kramer also offered his own opinions about the age of mass incarceration.

“I saw more and more of my fellows going to prison – first thousands, then tens of thousands, hundreds of thousands. Today we have 2.5 million,” he said.

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Leadfoot guitarist Mike Vanier will provide eight hourly group lessons to inmates at the jail’s Division 11.

He said he could help open the door to a whole new universe for inmates as he strummed a guitar.

“It does jazz, it can do blues,” Vanier said.

So far, 250 inmates have signed up for the ten available slots in the non-profit “Jail Guitar Doors” program, named after a 1978 song by The Clash, telling the story of Wayne Kramer’s imprisonment.

Dart told inmates signing up for the program “can change the way you think about yourself, and there’s a big connection between learning an instrument – you know, your fingers on a guitar – and going back up into your brain, that connection, it changes you.”

Kramer’s wife, Margaret Kramer, co-founded the program. She said the program can help make the jail safer.

“Corrections officers have told us that those inmates who participate, they’ve learned alternative ways to express themselves, and it has lowered the rate of violence on CO’s as well,” she said.

Dart urged the inmates to, “Turn your lives around and become beacons, instead of cancers in your communities.”

The sheriff has already offered inmates training in bee-keeping, fish farming, and gardening – as he seeks valid outlets for those who need something useful to do behind bars.

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