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Program Profile: Minnesota Prison-based Chemical Dependency Treatment

Evidence Rating: Promising - One study Promising - One study

Date: This profile was posted on June 10, 2011

Program Summary

Prison-based treatment for offenders who are chemically abusive or dependent. The program is rated Promising. Offenders who received treatment had significantly lower rates of reoffending. Completing treatment reduced the hazard for rearrest by 22 percent, for reconviction by 20 percent, and for incarceration by 27 percent. Increased treatment time was also found to have some impact on recidivism.

Program Description

Program Goals

The Minnesota Department of Corrections (MNDOC) provides prison-based chemical dependency (CD) treatment for offenders who are chemically abusive or dependent. The primary goal of in-prison treatment programs is to reduce the recidivism rates of offenders with CD issues once they reenter the community.


Targeted Population/Eligibility

CD treatment offered by the MNDOC is available in seven of the 11 State facilities that house female and male adult offenders. Offenders undergo a brief 20- to 40-minute CD assessment shortly after they’re admitted to prison in Minnesota. On average, about 85 percent of newly admitted prisoners are directed to get CD treatment based on the assessment that shows they are chemically abusive or dependent. The licensed assessors, who determine the CD diagnoses of prisoners, use Diagnostic and Statistical Manual of Mental Disorders (or DSM–IV) criteria for substance abuse. The criteria for abuse include experiencing problems at work or school, having financial problems, having legal problems, and engaging in dangerous behavior while intoxicated. The criteria for dependence include increased tolerance, withdrawal symptoms, inability to cut down or quit, and a lot of time spent acquiring, using, or recovering from use.


Although the vast majority of newly admitted prisoners are directed to enter CD treatment, not all offenders will have the opportunity to participate in prison-based treatment. This is because the number of treatment-directed offenders (more than 3,000 annually) is greater than the number of treatment slots available (about 1,800 annually). Inmates are instead prioritized to receive treatment based on offender needs and recidivism risk. The amount of time remaining to serve in prison is also another important factor considered when determining who receives treatment.


Program Components

The prison-based CD treatment is based on the therapeutic community model. Inmates in treatment are housed separately from the rest of the prison population. There are typically 15–25 hours of treatment programming per week, and the programs maintain a staff-to-inmate ratio of 1:15. The treatment programs also emphasize to inmates that it is their personal responsibility to identify and acknowledge their criminal and addictive thinking and behavior. CD programming includes educational materials that provide information on the signs and symptoms of CD, as well as the dangers and effects that drug use can have on the body and on family and relationships.


The MNDOC initially offered short- (90 days), medium- (180 days), and long-term (365 days) CD treatment programming. The short-term programming was discontinued in 2006, however, after evidence seemed to suggest that the short-term treatment programs weren’t as effective as the programs that were longer in duration. The medium- and long-term programs primarily focus on the relationship between substance abuse issues and criminal behavior. As inmates progress through the program, they are expected to increase their level of active participation in services. The programs include education, individual counseling, and group counseling components.

Evaluation Outcomes

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Study 1


The analyses by Duwe (2010) found that, compared to untreated offenders, those offenders who received prison-based chemical dependency (CD) treatment provided by the Minnesota Department of Corrections (MNDOC) had significantly lower rates of reoffending across all three recidivism measures (rearrest, reconviction, and reincarceration). Among offenders that received CD treatment, program completers had lower recidivism rates compared to program dropouts across all three measures. In addition, offenders who participated in medium-term programs had the lowest recidivism rates, followed by long-term program participants.


The Cox regression analysis, which can control for other factors that may impact the outcome results, showed the same result: participation in prison-based CD treatment significantly reduced the hazard ratio for all three recidivism measures. Treated offenders recidivated less often and more slowly compared to nontreated offenders. CD treatment decreased the hazard by 17 percent for rearrest, 21 percent for reconvictions, and 25 percent for reincarceration of a new crime.


Treatment Outcome

Dropping out of treatment (either quitting or being terminated from the program) did not have a statistically significant effect on any measure of the recidivism measures. Completing treatment did have a significant impact, however. Completing treatment reduced the hazard for rearrest by 22 percent, for reconviction by 20 percent, and for incarceration by 27 percent.


Program Duration

Both short- and medium-term programs had statistically significant effects on all three recidivism measures, while long-term programs did not have a significant effect. Compared to matched nontreated offenders, the hazard ratio for treated offenders in the short-term programs was 18 percent lower for rearrest and reconviction, and 24 percent lower for reincarceration. The hazard ratio for treated offenders in the medium-term programs was 32 percent lower for rearrest, 28 percent lower for reconviction, and 30 percent lower for reincarceration compared to the untreated matched group. This finding seems to suggest that increased treatment time lowers the risk of recidivism, but only up to a point.

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Evaluation Methodology

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Study 1

Duwe (2010) used a retrospective quasi-experimental design to examine the effectiveness of prison-based chemical dependency (CD) treatment provided by the Minnesota Department of Corrections (MNDOC) to reduce recidivism among chemically abusive or dependent offenders. The study compared recidivism outcomes between treated offenders and a matched comparison group of untreated offenders.


The main outcome of interest was recidivism, which was defined as rearrest, felony reconviction, or reincarceration for a new sentence. Recidivism data was collected on offenders through Dec. 31, 2008. The follow-up periods ranged from 36–48 months. Data on arrests and convictions was collected from the Minnesota Bureau of Criminal Apprehension. Data on reincarceration was collected from the Correctional Operations Management System maintained by the MNDOC.


Study participants included 3,499 offenders who were directed to enter CD treatment when they were admitted to prison after 2001. All of the offenders were released during 2005. Of these 3,499 offenders, 1,164 participated in CD treatment, and the remaining 2,335 were not offered treatment, primarily due to a lack of available space in treatment (35 were removed from this sample because they refused treatment). The study used the propensity score matching (PSM) method to control for selection bias and match treated offenders to nontreated offenders. PSM involves finding a predicted probability of selection (or a propensity score) that is estimated by a logistic regression model in which selection into the CD treatment is the dependent variable and the predictor variables included 17 control variables that could have had an impact on the selection process (such as sex, race, and prior felony conviction).


The PSM procedure resulted in matching 926 offenders in the treatment group with 926 offenders in the non-treatment group. The matched treatment group was 90 percent male and 43.5 percent minority, with an average age of 33.44 years at release from prison. The matched untreated group was 88.5 percent male and 45 percent minority, with an average age of 33.3 years at release. Due to the PSM process, there were no significant differences between the two groups.


The study also looked at the effects of treatment by comparing completers and dropouts in the treated group, and the effects of program duration by separating out treated offenders who participated in short-, medium-, and long-term programming. Separate PSM were estimated for each of the five measures of treatment:


·         Treatment completers (n= 843)

·         Treatment dropouts (n= 321)

·         Short-term program participants (n= 671)

·         Medium-term program participants (n= 393)

·         Long-term program participants (n= 100)


Untreated offenders were matched with treated offenders for each of the five treatment measures.


Survival analysis models were used to analyze the outcome results because they use time-dependent data, which was important to help determine not only whether offenders recidivated but also when they recidivated. The study also used the Cox regression model, which included both “time” and “status” variables in estimating the impact of treatment on recidivism. The “time” variable measures the amount of time from the date of release until the date of the first rearrest, reconviction, or reincarceration. For those who did not recidivate, the date of Dec. 31, 2008, was used. The “status” variable measured whether offenders reoffended during the period they were at risk to recidivate. The time offenders spent in prison as a result of violating supervised release was subtracted from their at-risk period, but only if it preceded a rearrest, reconviction, and reincarceration for a new offense or if the offender did not recidivate prior to Jan. 1, 2009.

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There is no cost information available for this program.
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Evidence-Base (Studies Reviewed)

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These sources were used in the development of the program profile:

Study 1

Duwe, Grant. 2010. “Prison-Based Chemical Dependency Treatment in Minnesota: An Outcome Evaluation.” Journal of Experimental Criminology 6:57–81.

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Related Practices

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Following are practices that are related to this program:

Incarceration-based Therapeutic Communities for Adults
This practice uses a comprehensive, residential drug treatment program model for treating substance-abusing and addicted inmates to foster changes in attitudes, perceptions, and behaviors related to substance use. The practice is rated Promising in reducing recidivism rates after release for participants in therapeutic communities.

Evidence Ratings for Outcomes:
Promising - More than one Meta-Analysis Crime & Delinquency - Multiple crime/offense types
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Program Snapshot

Age: 18+

Gender: Both

Geography: Suburban

Setting (Delivery): Correctional

Program Type: Alcohol and Drug Therapy/Treatment, Group Therapy, Individual Therapy, Therapeutic Communities

Targeted Population: Alcohol and Other Drug (AOD) Offenders, Prisoners

Current Program Status: Active

Program Director:
Steve Allen
Behavioral Health Services Director
Minnesota Department of Corrections
1450 Energy Park Drive, Suite 200
St. Paul MN 55108
Phone: 651.361.7292
Fax: 651.642.0223

Grant Duwe
Research Director
Minnesota Department of Corrections
1450 Energy Park Drive, Suite 200
St. Paul MN 55108
Phone: 651.361.7377
Fax: 651.642.0223