(CBS News) PARCHMAN, Miss. - In 1990, when former prison guard Christopher Epps was the deputy superintendent at the Mississippi State Penitentiary in rural Parchman, he oversaw the construction of a maximum security wing to keep troublesome inmates in solitary confinement.
It was called Unit 32, and it housed up to 1,000 men inside eight-foot by ten-foot cells 23 hours a day. Their amenities were a concrete bunk, a tiny metal writing table, and a steel sink and toilet. They ate meals alone in their cells and got out only for exercise and a shower.
"That was the culture that we were taught, and we grew up in. Obviously, that's all changed now," Epps said in an interview.
What's changed for Epps and a growing number of prison professionals around the country is their dimming view of the effectiveness and expense of solitary confinement, as well as the realization of its mental and physical toll on inmates.
"Ninety-five percent of them are going to be released and live in your and my neighborhood," Epps said. "We're in the business of corrections. We're in the business or rehabilitation."
Evidence that solitary confinement controls violence or curbs misbehavior has been scarce, while solitary confinement makes matters even worse for the increased number of people with mental illnesses who are incarcerated.
In the old days, anytime an inmate misbehaved, Epps said, prison officials didn't take any chances and placed him in a single cell away from the general population. An inmate would then have to prove his good behavior for a very long time to be transferred back.
The reasons for being sent to solitary were varied and subjective -- from refusing work assignments on Parchman's sprawling 1,800 acres of farm land, to fighting with other inmates. Six-month or year-long stints in solitary were not unusual. Epps knew one inmate who was held in solitary for five years.
"They change physically," Epps said. He saw one inmate's hair go completely gray in six months. "It is my belief it affected them mentally."
Kirby Tate was one of those inmates greatly affected by solitary confinement.
"It's torture. It's the worst kind of torture. I'd rather be beaten or burned," Tate said in an interview.
Tate, 48, a father of three, served nine years for marijuana possession, before being pardoned by former Mississippi Gov. Haley Barbour and released last year. Tate spent three of those years behind bars in solitary confinement, sometimes bearing summer temperatures exceeding 120 degrees inside a non-air conditioned cell with a solid steel door.
"You get your sheet, and you stick it in a toilet, and you get it all wet, and you lay it across you, and lay on your rag until it dries out," Tate said. "It takes about 10 or 15 minutes of drying, and you do it over and over and over and try to keep from dehydrating."
Tate said the isolation was debilitating -- no family visits, no phone calls, nightmares, hearing voices inside his head.
"Every bad thing that ever happened to you in your life. Every sad thing, every embarrassing, depressing thing, you relive it," Tate said. "You pray to die. You lay in bed every day and you pray, 'Please let this be the last day.'"
Tate felt he never got a fair hearing as to why he was moved to solitary confinement. Before one stint, he said he was told that another inmate had identified him as a gang leader, which Tate said was untrue. Tate said he understands some inmates need to be segregated for safety reasons, but he believes solitary confinement should be rare.
"I met a bunch of guys in prison that are hazardous to the health at anybody they can get at," Tate said. "If you're not a psychopathic maniac, and you're not fixing to kill everybody you can get, they've got no business putting you in solitary confinement."
In 2002, Epps moved up to become Mississippi's statewide department of corrections commissioner, a position he still holds.
In 2007, the American Civil Liberties Union brought a lawsuit against Epps describing the harsh conditions of solitary confinement as inhumane and asserting criteria for detaining inmates in solitary confinement was arbitrary.
James Austin, from the National Institute for Corrections, found 80 percent of the inmates in Unit 32 did not need to be there.
That summer, there were multiple stabbings, three murders, and one suicide inside Parchman's Unit 32.
In 2010, as part of a settlement with the ACLU, Epps ordered the closing of Unit 32 and started rolling back the use of solitary confinement across his state.
"They convinced me to try their way, and I am glad I did," Epps said.
A step-down system was introduced with incentives for inmates to stop misbehaving. Inmates could be moved from a cell with a solid door to one with bars that let in more light and air. Instead of being led to the shower room with handcuffs behind his back, an inmate could go unrestrained. There could be unrestrained leisure time and time to mingle with other inmates and staff. Gradually, hundreds were transferred to Parchman's general population.
A second lawsuit by the ACLU led to the abolition of solitary confinement for juvenile offenders in Mississippi.
"What happens when you do that to an individual, particularly when they're so young, is it you take away all hope," Epps said. "We are hoping that we can change their behavior and they can come out and be productive citizens."
New rules limit solitary confinement to adult inmates with serious infractions, to gang leaders, prison escapees, or those who pose a threat to the safety of other inmates.
In 2007, there were around 1,300 inmates held in solitary confinement across Mississippi. Today, according to the department of corrections, there are slightly more than 300, a decrease of 75 percent.
Around 15 inmates are held in solitary confinement in another building at Parchman, with the rest in clusters at 14 other prisons. Most of these inmates are involved in educational programs, mental health counseling, and treatment for alcohol and drug addictions.
"It has not affected public safety for the citizens of our great state. It has not affected our staff. No one has gotten hurt," Epps said. "So I feel like we're on the right road."
A re-examination of solitary confinement is underway in several states, with Colorado, Maine, and Georgia among those initiating reforms.
The federal Bureau of Prisons hired a contractor last month to conduct an independent review of the use of solitary confinement in federal prisons.
Cost is another factor. In Mississippi, Epps, said, it costs $102 a day to detainee someone in solitary confinement, compared to $42 a day for an inmate in the general population.
By closing Unit 32, Mississippi saved $6 million a year out if its $362 annual corrections budget. The state has approximately 22,600 people in its prisons.
To create greater incentives for good inmate behavior, Epps lobbied the state legislature to amend a "truth in sentencing" law that had required all inmates to serve 85 percent of their sentences before becoming eligible for parole. The law now grants inmates 30 days of earned time for every month served without incident, so the average inmate in Mississippi now serves slightly more than half of his sentence.
"If you are serving time in Mississippi, and you've never been convicted of a violent crime, and you're currently serving for a nonviolent crime, we're going to give you a parole date," Epps said.
He points to reduced recidivism rate of 27 percent over a three year period, one of the lowest in the country.
Epps is touting Mississippi's reforms from his national perch as the new president of the American Corrections Association.
"We're getting the word out" Epps said. "The word has gotten out that it can be done, and it saves money, and it doesn't affect public safety, and that's the bottom line."