The Law: Shock Probation

For many a first offender, the worst part of prison comes in those shocking first days behind bars. Stunned by the strip search on entering, the frightening, unfamiliar vastness of the prison and the long incarceration stretching ahead, the new inmate is overwhelmed. On the theory that the first taste of prison may have at least as much curative effect as the full dose, a few states, including Indiana and Ohio, have quietly been practicing what they call "shock probation."

Eight months ago, Kentucky be came the latest state to try the experiment. Under its law, an offender sent to jail...