Not really, but no one is sure. But, a little goes a long way in a huge expenditure, and prisons are just that. What private prisons do is cut. They cut red tape. They cut a little time during the building, the prisons go up quicker, staff isn't trained very long and require even less in the way of background and education than their public counterparts.
Public money turns into private profit and everyone is happy.
I am not happy though. My brother is a prisoner of the drug war. I went to visit him a few weeks ago, he was sent there a year ago and has been down a long time now. The prison rises foreboding in the midst of what was once an Arkansas bean farm. My brother wrote of it not long after they moved him there from a prison in Wisconsin.