The Minnesota Prison-Based Sex Offender Treatment Program (SOTP) provided by the Minnesota Department of Corrections (MNDOC) offers treatment, therapy, and transitional services to convicted male sex offenders in prison. The SOTP uses a cognitive–behavioral framework to provide long-term intensive sex offender and chemical dependency treatment that is consistent with the risk–needs–responsivity model.
To be eligible for the SOTP, offenders must have at least 20 months to serve in prison. Because treatment capacity doesn’t always keep pace with the growing prison population, the SOTP targets moderate- to high-risk sex offenders for treatment. Low-risk sex offenders who are unable to enter treatment while incarcerated are referred to community-based treatment at the time of their release. Under the current process, priority for treatment is based primarily on offenders’ scores from the following actuarial instruments: Static–99, Rapid Risk Assessment for Sex Offense Recidivism, and Minnesota Sex Offender Screening Tool (Revised).
The choice to enter treatment in prison is not entirely voluntary. After inmates receive a treatment directive, they have a right to refuse treatment. However, there are consequences to this decision. Offenders who do not comply with the treatment directive may have their wages frozen, or they may be subject to extended incarceration disciplinary time that results in a longer prison stay. Treatment participation (or nonparticipation) is an item on the Minnesota Sex Offender Screening Tool (Revised), which has been used to guide decisions about community notification levels and civil commitment referrals.
Inmates in the SOTP are housed in two adjacent wings of a larger living unit. The living units operate within a modified therapeutic milieu, which includes clear living unit/program structure and rules. Inmates meet weekly with other members of their living unit to address general housekeeping issues and community cohesion, and to provide support to one another as a community. The SOTP is not a closed living unit, and inmates in the program have some interaction with the general population during movement and activities such as dining, religious services, or educational programming.
Eligible sex offenders start the program in a 30-day assessment phase. The assessment phase includes psychological testing, completion of assignments to facilitate the assessment of treatment needs, and a review of offending history and offense dynamics. There is also a lecture, discussion, and videotapes to provide information on treatment participation and expectations, defenses and denial, sexual assault dynamics, victim impact, and chemical dependency. In addition, a written psychosexual assessment report and an individualized treatment plan is developed based on information gathered from clinical interviews, client observations, and test results.
Following the assessment phase, inmates participate in an average of 6 hours per week of staff-facilitated group therapy sessions. Therapy groups are also available for inmates with cognitive/intellectual limitations to address their particular needs. Additional individual therapy sessions are offered based on the specific needs of inmates and the availability of staff. Therapy is provided in progressive phases and includes transitional programming as well as aftercare. Ongoing therapy and postrelease programming is provided in the community by private agencies under contract with the MNDOC.
Another component of the SOTP is treatment for chemical dependency. Offenders who enter the MNDOC are formally screened, assessed, and diagnosed for chemical abuse or dependency. Treatment plans are developed based on the outcome of these assessments. For sex offenders needing treatment for alcohol or drug dependency problems, treatment is typically provided following the assessment phase of the SOTP.
In addition, education sessions are facilitated between inmates and members of their family and/or support system to prepare offenders for their return to the community as well as to help them reach specific treatment goals. During these sessions, information is provided about the nature and impact of the inmates’ offending, and support persons are informed about the risk for reoffense. Response strategies for the offender and the support person are also developed during these sessions.
Inmates also participate in psychoeducational programming, which varies according to offenders’ individualized treatment plans. Classes are usually provided for 1½-hour sessions, three to four times a week in 12-week (quarter) terms. During each quarter, inmates are enrolled in one or two classes, including the following: Emotions Management, Alcohol and Drug Education, Cognitive Restructuring, Sexual Health, Domestic Abuse, Sexual Assault Dynamics, Reoffense Prevention, Victim Empathy, Personal Victimization, Grief and Loss, Morals and Values, and Transitional Curriculum. Modifications are made to some of the classes to address the particular needs of inmates with cognitive/intellectual limitations. Additional classes, such as classes on parenting and transitional planning (housing, employment, transportation, etc.) are also available. Inmates in the SOTP also attend additional support groups, such as Alcoholics Anonymous, Narcotics Anonymous, and Sex Abusers Anonymous. Meetings are held in the institution and groups meet on a weekly basis for about 1½ hours a week. The groups are monitored, but not facilitated, by program staff. Although individualized treatment plans vary widely among participants, the average dosage consists of 10 to 15 hours of direct staff facilitated services per week for a duration that can range from 1 to 3 years.
The results from the study conducted by Duwe and Goldman (2009) suggest a significant but modest reduction in sex offender recidivism. The results showed that inmates who participated in the Minnesota Prison-Based Sex Offender Treatment Program (SOTP) recidivated less often and more slowly than untreated inmates. Treated offenders survived longer in the community without committing a new sex offense. Controlling for other factors, the SOTP significantly reduced the hazard ratio for a new sex offense rearrest, decreasing it by 27 percent.
The results showed that the SOTP made a statistically significant impact on violent offense recidivism. Compared with the untreated offenders, the hazard ratio for a violent rearrest was 18 percent lower for treated sex offenders.
Participating in treatment also had a statistically significant effect on general recidivism. The hazard ratio for rearrest for any offense was reduced by 12 percent for treated offenders, compared with untreated offenders.
Type of Sex Offenders
Treatment was not found to be significantly more, or less, effective for certain types of sex offenders. This suggests that treatment may work equally well not only for adult rapists and child molesters but also for incest offenders and those who victimize acquaintances or strangers.
Duwe and Goldman (2009) used a retrospective quasi-experimental design to assess the impact of the Minnesota Prison-Based Sex Offender Treatment Program (SOTP) on sex offender recidivism. The study compared recidivism outcomes between treated offenders and a matched comparison group of untreated offenders who were released between 1990 and 2003.
During this 14-year period, there were 3,440 sex offenders who were released from Minnesota prisons. Of these offenders, 1,493 participated in prison-based sex offender treatment before their release. Of the remaining 1,947 offenders, 105 refused to participate in treatment and 1,842 were not given the chance to participate. The 105 treatment refusers were removed from the study to avoid biasing the results. Propensity score matching was used to match treated to untreated offenders by estimating a logistic regression model in which the dependent variable was participation in prison-based treatment. The process did not yield a match for all treated offenders but resulted in 1,020 matches (68.3 percent of the total number of treated offenders). The treatment group was 35.2 percent minority, with an average age of 34.9 years. The untreated group was 35.1 percent minority, with an average age of 34.9 years. Following the propensity score matching, there were no significant differences between the two groups.
The main outcome of interest was recidivism, which was measured in nine different ways. It was first operationalized as rearrest, reconviction, or reincarceration for a new offense following an offender’s first release from prison. Recidivism was further categorized by type of offense, including sex offense, violent offense (including sex offenses), and any offense. Sex offense was defined as a first- to fifth-degree criminal sexual conduct offense. Violent offenses included homicide, assault, robbery, and kidnapping in addition to sex offense. Arrest, conviction, and incarceration data was collected on offenders through Dec. 31, 2006. The minimum follow-up period was 3 years, and the maximum was 17 years. Data on arrests (misdemeanor, gross misdemeanor, and felony) and convictions (misdemeanor, gross misdemeanor, and felony) was collected from the Minnesota Bureau of Criminal Apprehension. Incarceration data was collected from the Minnesota Department of Corrections’ Correctional Operation Management System.
The statistical technique used in the study was the Cox regression model, which used both “status” and “time” variables in estimating the impact of the independent variables on recidivism. The “status” variable was one of the recidivism variables (for example, sex crime rearrest and violent crime rearrest). The “time” variable measured the amount of time (in days) from the date of release until the date of first rearrest, reconviction, reincarceration — or Dec. 31, 2006, for those who did not recidivate. The study included estimated Cox regression models for each of the nine recidivism measures for both treatment variables (participation and outcome). However, given that the reconviction and reincarceration results for all three reoffense types were substantively similar to those for rearrest, only the findings for rearrests are presented because rearrests was the most sensitive recidivism measure.
To accurately measure the total amount of time an offender was actually at risk to reoffend (that is, “street time”) the study had to account for times when an offender was not at risk to recidivate following release from prison, including the time that offenders spent in prison as supervised-release violators. This time was subtracted from their total at-risk time period. It was also necessary to account for the time that offenders were civilly committed and incapacitated in a mental health institution.