It cost about $100K a year to keep people in prison. Just maybe some of them would like to go and settle Mars instead of staying in prison. It might make since

It cost about $100K a year to keep people in prison. Just maybe some of them would like to go and settle Mars instead of staying in prison. It might make since to pay their way. One could imagine an entire colony of such prisoners developing and preparing Mars for the rest of us in return for paying off their debt to society and their transportation to Mars .... :)