Some percentage of the population is comprised of violent sociopaths. Those people need to be locked up for the safety of the rest of us. People who have committed victimless crimes, like minor drug use, should almost never be incarcerated. People who have defrauded other people in some way, including petty larceny, should be punished by some means other than incarceration.

Pretty much what I'm saying is that jail time should be reserved solely for the violent.