Thus, the major controlling policy variable for prison overcrowding currently seems to be the three-strike type of mandatory sentencing for drug use that is in effect in more than twelve states. It could be that drug policy is working against both sensible prison policy and justice administration. As indicated, a major perhaps unintended consequence of the mandatory sentencing laws has been to fill prisons with petty, nonviolent, frequently first-time offenders, Almost 90% of first-time offenders in federal courts went to prison in 1990 with an average sentence of more than five years; first-time violent