Just a quick link here to an article from a few weeks ago that recalls Bay County, FL's experience in having CCA manage their jail. In the words of the Sheriff, the facility was "a horrible, nasty, unbelievable mess," and shortly after the county signed its contract with CCA, CCA began to jack up the price the county would pay per prisoner. For what clearly amounted to high-quality services. After the county resumed operations of the facility, they were able to save millions of dollars compared to CCA, even after performing extensive maintenance that CCA had neglected, since they eliminated the profit motive from the equation.
This came out during the whole commotion about the state legislature's boneheaded plan to privatize half the prison system, but serves as a great cautionary tale of the risks of privatizing any prison.