I believe if a lot less wrongdoers were offered 3 hots & cot plus full medical/dental on the taxpayers teat as reward for their wrongdoings this nation could spend those billion$ on improving itself in areas lacking like education in useful real world job skills/trades and real border security. Prison time for any crime where harm was done to life or limb just seems like throwing good money after bad actions. Not only is the guy not out their making money to help build the economy, he is an expensive drain on it instead. If the wrongdoers are not honorable enough to A) know not to harm their fellow man and/or B) are unwilling to work to compensate victims for the wrongdoing while alive, they are more than welcome to figure out how to be honorable in death so we don't provide support for their immoral lives.
Of course then the flip side to that is that our justice system is operated by fallible members of mankind who can and do make mistakes along the way to sending people to meet their maker, so who wants to be the guy that mistakenly sends an innocent man to his death? Chain gangs seem like a middle ground, there are a lot of dirty jobs out there that could be completed by those who are unable to handle the responsibility that comes with freedom. "Freedom is the right to be wrong, not to do wrong" is a very simple yet powerful quote to ponder. "Common sense is not common enough" is another.