The Intensive Supervision Probation (ISP) program in California was designed to ensure public safety while also relieving prison crowding. ISP is a more stringent form of probation and involves increasing the level of supervision and monitoring that the person on probation is subject to, and is deemed more appropriate for supervising individuals whose risk of recidivism is deemed to be high.
Target Population and Sites
Beginning in 1987, the ISP program was implemented separately in three counties in California: Contra Costa, Ventura, and Los Angeles. The program targeted individuals at higher risk for committing offenses, as determined by the National Institute of Corrections’ risk–needs instrument. These sites responded to a 1986 Bureau of Justice Administration request for proposals, with each offering to implement a stricter supervisory regime for the higher-risk probationers, as the number of probationers in California as well as caseloads had increased. The sites had concerns over their ability to adequately supervise these individuals in a manner that could ensure public safety within the regular probation system.
The intervention is characterized across sites by increased contacts between probation officers and probationers, reduced caseloads for officers, and gradual transition to regular probation for successful participants. Beyond its core components, the implementation of ISP in California varied across the three sites.
In Contra Costa County, the program was targeted toward adults convicted of drug offenses and included three stages of supervision with gradually decreasing levels of face-to-face visits, phone calls, drug tests, and general monitoring. It also included employment services, counseling and referrals, random drug tests, and police involvement in violations.
In Ventura County, the target population consisted of adults convicted of felonies, and the intervention consisted of the same components as in Contra Costa County, with the addition of victim restitution requirements, job training, and remedial education services.
The implementation of the program in Los Angeles County was the least intensive; it included three levels of monitoring, consisting only of face-to-face visits and phone calls.
Petersilia and Turner (1992) found that the program significantly increased the number of technical violations of the ISP participants in Contra Costa County.
Overall, the preponderance of evidence suggests that the Intensive Supervision Probation (ISP) program did not significantly and consistently improve outcomes for the treatment group.
While Petersilia and Turner (1992) found that the ISP group in Ventura County was significantly less likely to be arrested, there were no statistically significant differences at the two other sites (Contra Costa and Los Angeles Counties). When controlling for time at risk, there were no statistically significant differences at any site.
The treatment group in Contra Costa was more likely to have a technical violation, compared with the control group. However, this result may be due to increases in the supervision and monitoring of the treatment group. There were no statistically significant differences at the other two sites (Ventura and Los Angeles Counties).
Petersilia and Turner (1992) used an experimental design to evaluate the impact of the Intensive Supervision Probation (ISP) program on recidivism outcomes. The study population consisted of high-risk probationers in Contra Costa, Ventura, and Los Angeles Counties, California. Most individuals were sentenced to 6 months in jail followed by 3 to 5 years on probation; however, the study did not indicate the exact percentage of the sample who received split sentences.
Each site developed its own eligibility criteria, determined which probationers were eligible for ISP, and passed that information on to the researchers, who then randomly assigned eligible individuals to either the ISP program or to routine probation. By 1989, the three sites had each collected enough data for researchers to evaluate 1 year of follow up for all individuals in the program. Because the assignment of probationers to treatment or control groups was random, statistical controls were not used in the outcome analyses. There were only two significant differences between study groups across all of the sites: 1) a higher percentage of ISP probationers than regular probationers had a high need for drug treatment in Contra Costa County, and 2) ISP probationers in Los Angeles County were older than their counterparts on routine probation. The researchers determined that neither of these characteristics was related to recidivism within the site.
In Contra Costa County, the 170 study participants were 81 percent male, with an average age at current conviction of 28 years, and an average of six prior arrests. The ethnic breakdown was 79 percent African American, 18 percent white, and 3 percent Hispanic. In Los Angeles County, the 152 study participants were 87 percent male, with an average age at current conviction of 29 years, and an average of seven prior arrests. The ethnic breakdown was 86 percent African American, 11 percent Hispanic, and 3 percent white. In Ventura County, the 166 study participants were 85 percent male, with an average age at current conviction of 30 years, and an average of seven prior arrests. The ethnic breakdown was 50 percent white, 35 percent Hispanic, and 15 percent African American.
Recidivism was defined as rates of new arrest and technical violations. Chi-square tests were used to compare differences in rates of new arrest and technical violation variables across each site’s study groups.
The Petersilia and Turner (1992) study provided a breakdown of the costs of the program and its comparisons. When including court-related reprocessing costs, the Contra Costa Intensive Supervision Probation (ISP) cost $7,240 on average per participant, compared with $4,923 for routine probation during the 1-year follow-up period. In Ventura County, the cost was lower for the average ISP participant, at $8,548, compared with the cost for the average participant in the Community Resource Management team comparison condition, which was $9,606. Finally, in Los Angeles, the average cost per ISP participant was $8,902, compared with $7,123 for routine probationers.
Evidence-Base (Studies Reviewed)
These sources were used in the development of the program profile:Study 1
Petersilia, Joan, and Susan Turner. 1992. “An Evaluation of Intensive Probation and Parole in California.” Journal of Criminal Law and Criminology
These sources were used in the development of the program profile:
Petersilia, Joan, Susan Turner. 1990. “Comparing Intensive and Regular Supervision for High-Risk Probationers: Early Results from an Experiment in California.” Crime & Delinquency
Petersilia, Joan, and Susan Turner. 1990. Intensive Supervision for High-Risk Probationers Findings from Three California Experiments
. Oakland, Calif.: RAND.