The New York Times quotes SLS Professor Joan Petersilia on how prison alternatives have failed to lower recidivism. 

Several misconceptions underlie the deincarceration movement and its efforts to increase diversion from prison.

Prisons are assumed to be filled with harmless sad sacks who smoked a few joints and got caught. In fact, prison remains a lifetime achievement award for persistence in criminal offending. Criminals are already given numerous opportunities for supervision and programs in the community before they are finally sentenced to prison, as illustrated by the criminal justice history of Tyrone Howard, alleged murderer of New York Police Officer Randolph Holder. The average number of prior convictions for inmates released from state prison in 2005 was five, the average number of prior arrests was over 10, according to the Bureau of Justice Statistics. The JFA Institute has estimated that in only 3 percent of violent victimizations and property crime does the offender end up in prison.

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In the 1990s, virtually every state implemented intensive supervised probation programs to divert offenders from prison. Not only did these programs not lower recidivism, if anything they worsened it, according to Stanford law professor Joan Petersilia. California’s Proposition 36, passed by voters in 2000, offered nonviolent drug offenders free drug treatment in lieu of incarceration. Arrests increased, even among those who completed treatment, according to Pepperdine University public policy professor Angela Hawken. Most offenders never showed up or went AWOL from their treatment program.