They didn't set an expiry. It's my only complaint.
After some thought, assuming that everything Farsight tells me is true, I kind of come to terms with the prison planet scheme. Perhaps it's just a means of my exerting diplomacy.
I'm not particularly bothered by the idea of a prison planet overall. People are bad enough, you can't get rid of them, there's a whole industry of merchants happy to take them off your hands. So the equation is satisfied. You do the crime, you do the time. Who knows, perhaps I lived a life at one time that warranted some prison time. I don't really feel it in my bones but I get the idea.
So the only complaint I have is there was no expiry date. Should we find our emancipation, I would probably advocate that we do continue arranging a prison service, but we don't deal with people who think it's ethical to throw away the key.
Don't waste too much time on this thread, but just a thought.