system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How are private prisons legal?

I've been wondering how it's legal for a private organization to incarcerate a federal/state prisoner (or any prisoner of the government for that matter).
gpt
How is the government hiring a company to manage prisoners different from the government hiring guards to manage prisoners?

The company does not decide who goes to prison or for how long, the government does. The government also sets the standards for how prisoners are to be treated, and has a responsibility to enforce those standards - just like it does for state-run prisons.