Here's what they found. Despite the fact that two of the three for-profit facilities - all three of which are operated by Corrections Corporation of America - are supposed to be minimum security facilities, they consistently had higher incident rates than their publicly-operated counter-parts, most of which had higher security designations.
"According to an analysis of incidents involving assaults and disturbances at publicly-operated and privately-managed prisons in Tennessee from January 2009 to June 2011, incident rates were consistently higher at the state’s three private prisons. Data obtained from the Tennessee Department of Correction (TDOC) recorded incidents in 11 categories related to assaults on inmates, assaults on employees and institutional disturbances. Data was reported for the state’s 11 prisons operated by the TDOC, as well as three facilities that house state prisoners run by Nashville-based Corrections Corporation of America (CCA).
In terms of rates per 1,000 prisoner population, the privately-operated prisons had notably higher incident rates. For 2009, the average rate of incidents at the 11 state-run prisons was 13.92 per 1,000 population, while the average rate at the three CCA facilities was 18.68 – 34% higher than at TDOC prisons. The 2010 average rate of incidents at TDOC facilities was 14.51 per 1,000 population and the average rate at the CCA prisons was 18.68 – 28.7% higher than at the state-operated facilities. During the first six months of 2011, the average rate of incidents at TDOC prisons was 15.0 per 1,000 population while the average rate at the CCA facilities was 17.44 – 16.2% higher than at the TDOC prisons."
Alex Friedmann from PCI puts the findings in context:
“This research confirms what other studies over the years have found – that privately-operated prisons have higher rates of assaults and other violent incidents than their public counterparts,” said Alex Friedmann, president of the Private Corrections Institute (PCI), who conducted the Tennessee research. “For example, according to an Associated Press report earlier this month, a CCA facility in Idaho had more assaults than all other Idaho state prisons combined, based on 2010 data.”