In California, six out of 10 inmates will return to prison within three years of being released. But a drama workshop run in prisons by Hollywood actor Tim Robbins appears to cut this recidivism rate in half - by giving prisoners a chance to explore their emotions, and to gain some control over them.
In the Actor's Gang workshop, prisoners put on the clothes and make-up of characters from a type of theatre called commedia dell'arte - such as Pierrot, Harlequin or Columbine - and start improvising.
"We demand the truth from them by asking them to play a character to express extreme emotion, we encourage them to use their imagination," says Tim Robbins.
"They are playing so they can express the incredible rage they feel through these characters and they can express the intense sorrow and true fear they have, and the joy that's still there."
The project, which Robbins runs with a British woman, Sabra Williams, has now been going for six years. It began in one prison, with funding from private donors, and is now running in six, supported by funding from the state of California.
In many cases it is the only form of rehabilitation prisoners will get before they are released. And there is now growing evidence that it works.
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"A study came back in December that shows that for those men who took the acting class there is an 89% reduction in infractions, fights within prison, which is huge for the safety of the prison itself and the safety of the corrections officers," Robbins says.
"They have to deal with a lot less from the people who have been through our programme."
Another preliminary study suggests that the state's 60% recidivism rate is more than halved for people who have been through the Actor's Gang programme.
"That is the key to rehabilitation, that they stay out of prison. And we now have the evidence that our programme does that," Robbins says.
In 2012 I went to NORCO prison in Los Angeles to watch the Actor's Gang Prison Project in action for a BBC Radio 4 documentary. This year I went back to see whether it had helped the inmates stay out of trouble.
This is what they said - followed at the bottom of the page by Tim Robbins's account of what it has meant for him.
David De La Torre
One of them was David De La Torre, who was once a member of a Hispanic gang in LA and served 15 years for armed robbery and discharging his weapon in a movie theatre. Taking part in the Actor's Gang project made him "feel human again" for the first time after 12 years in prison, he says. Now a free man, he spends much of his spare time and spare cash going to theatres.
"I am wicked, I didn't go to prison for stealing apples… I was a violent person; I would get into lots of fights and riots inside. There was a lot of racial tension and I was a hard core racist but this project really mellowed me out," he says.
The prison was racially segregated, but Robbins and Williams deliberately ran a mixed-race course, and watched as the actors bonded. David had not experienced this kind of camaraderie before.
"I was doing something with a bunch of guys and when you have something like that in the back of your head you have that grace period, a little sliver of time to make a choice before doing something stupid like getting in a fight and that, man, I can't tell you how much that meant to me at the time and even now.
"The Actor's Gang programme teaches you how to control your anger and emotions and that's what sets me apart from the other guys who get released from prison. I still get mad but I can control it. I don't just slap someone, I have the tools to control myself. We check into the Parole Office and you see the people you get released with, then you just don't see them no more, they have violated and are back in and no-one from The Actor's Gang has gone back in. They are all still out."
Michael was jailed for five years for causing great bodily injury with a firearm. When he was let out the first time he stood in front of a door he expected someone to unlock it for him. Getting back into society was a very hard transition.
"In prison if you disrespect someone in prison or they disrespect you that's the trigger, that's the thing that will kick off everybody going off. Outside, especially with their phones, people are bumping into you all the time and I am used to people saying, 'Excuse me,' but it's not like that so I find that very difficult - people being rude and not thoughtful."
Like David, Michael uses the tools he learned in the Actor's Prison Project to keep his emotions in check.
"Something I still do, when I pass a mirror, is practise the facial expressions we learned in the acting class, the emotional states, just to remind myself. It's a daily reminder that you can control your emotions."
Gio was only 19 years old when he was convicted of domestic violence and burglary and sentenced to five years in prison. In 2010, at the age of 20, he was placed in a solitary confinement cage for 23 hours a day, with only one hour a day to eat breakfast, lunch and dinner and have a shower.
After this experience, putting on makeup and playing a character was empowering, he says.
"I had never been exposed to such transformative tools. There is a small community of people who have allowed me to feel normal again and Tim Robbins is one of them. I felt normal in an environment that was not normal for a 22-year-old.
"The Actor's Gang programme was the first opportunity I had to allow my past to empower me rather than define me and made me into a better man rather than a bitter man."
Gio is now enrolled in a college course in LA and is about to open his own restaurant, but every day he still wakes up thinking he is in prison. "It's been a recurring dream for two years now," he says. "I think about what transpired for half a decade and I think am I really above water now. I'll have a whole night dreaming of being inside and then I'll wake up and feel I am finally above water."
What an amazing feeling
Tim Robbins, who famously played a prison inmate in the 1994 film, The Shawshank Redemption, says he may actually get more out of the Actor's Gang project than the inmates.
"This is so much more fulfilling, to be in this struggle and the exploration of it, than any $1,000-plate dinner I had been to.
"It puts that other crap that people in this industry deal with into perspective - 'Where am I? Who am I? What's my last movie? How successful I am, what's my current rating?' It's a nightmare really, a self-obsessed nightmare of survival in Hollywood and here was an opportunity to throw all that away and figure out how to help this dude and if you can get through to this guy. What an amazing feeling to be able to see someone change from a darkened, negative shut-off person into a sentient human being and potential leader of men.
"Rather than chase Shawshank Redemption, which is not going to happen again, what else is there in life that you can achieve to create something new in, find some idea of achievement in? Surprisingly it has been this. The trap a lot of people fall into in this industry is that they try to [re-]create what was, in a misguided attempt to stay relevant."
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