A Terrible Idea

Prisons for profit may be one of the worst ideas that conservatives have come up with. Right-wingers would like to think that the private sector can always do everything better than the government. That is simply not true, and prisons are one area where government does much better. As the picture above implies, when you build a private for-profit prison you must fill it with prisoners (so the private owners can maximize their profit -- which can easily lead to people being sent to prison, when they could have been dealt with in a less restrictive and more effective way.
Private prisons are also just lawsuits waiting to happen (which the government would be liable for, since they send the prisoners there and pay for their keep). They pay their guards less, and therefore get an inferior quality employee (who is probably not properly trained, since training costs money). The owners also have the desire to cut corners on food, medical care, and other things to squeeze out a little bit more profit -- most of which could easily result in other lawsuits, since the Supreme Court has ruled that prisoners have a right to decent food, good medical care, and proper shelter.
The government sends people to prison, and that means the government is responsible for those people while they are in custody. Putting them in the care of a for-profit penal institution is just asking for trouble (which will surely come). And in the long run, it will be more expensive.