Some governments have run them wisely, but perhaps not enough of them. Today, we are, supposedly, more enlightened than in past centuries, or even past decades. In today's prisons, food is better than it once was, certainly there is a punishment factor in depriving someone of freedom, rehabilitation is supposed to be a major goal, mainly through education programs, and, finally, when someone has paid his debt to society, he is permitted to return to that society. In order that such things as rehabilitation should happen, well run government prisons offer inmates educational opportunities, as well as help by way of counselling, plus treatment to overcome such things as addiction to drugs. However, if government turns the running of our prisons over to a private company, profit becomes the motive, rather than rehabilitation, or even punishment.
Private companies are in business to make money - and only that.
In the United States, that has led to instances in Louisiana where judges have ordered youths removed from custody because they were so poorly treated. That particular prison was run by Wackenhut Corrections Corporation, the world's largest for-profit prison operator. The current move by our provincial government towards company prisons seems to me to be very similar to a move around 1996 to privatize the Liquor Control Board of Ontario. The LCBO was a sound operation, well run, and actually showed a profit. After an outcry, the government backed down on that issue, and rightly so.