I don't think it even needs to be controlled by the same people. Look at TurboTax. They built a company to make an insane tax code easy and they lobby against simplifying it.

Once it's big business there's a huge finical and employment incentive to keep the machine running no matter who's running it. Some might say that privatising prisons would even make it worse.

It's hard to stop a multi-billion dollar industry but what the prison system is doing to our population is not OK.