Turn them loose and they return to prison in astonishing numbers. One-hundred-thousand inmates are released each year from California prisons. Even a small drop in recidivism means thousands of crimes not committed.
"There are groups that don't recidivate as high as you might expect. People who have serious offenses don't always recidivate as far as often as people who have relatively minor ones," said Dr. Steven Chapman, California Department of Corrections and Rehabilitation.
The prisons are filled predominately with men. But women who make up one-tenth of all parolees are 15 percent less likely to return to prison than men.
Nearly 75 percent of ex-convicts who commit new crimes do it within a year of their release. The older an ex-convict gets the less likely he or she will commit another crime.
So within one year, 75 percent of the ex-cons will commit another crime. Seventy-five percent of them are 18 to 24 years old. After 60, recidivism falls to 46 percent among the ex-cons.
"Of the people who come back in three years, about 70 percent of them come back on a parole violation," said Chapman. "But consider when you're looking at a sex offender, for example, who is loitering around places where he or she shouldn't be, then, to violate them on that, probably is a really good practice."
The only encouraging news is a small drop in recidivism in the first year of release. That's followed by a slight increase in imprisonment among the ex-cons within the first three years of release.