The effectiveness of treatment for sexual offenders

The effectiveness of treatment for sexual offenders PDF Version (93KB)

Research summary
Vol. 7 No. 4
July 2002


Does treatment keep sexual offenders from reoffending?


Sexual offences are among the crimes that invoke the most fear and concern. Most sexual offenders are supervised in the community and virtually all will eventually be released. Consequently, there is an expectation that correctional systems should make reasonable efforts to reduce the chance that identified sexual offenders will reoffend. One common approach to managing sexual offenders is to provide specialized treatment programs. A number of different treatment programs have been operating, but there has been controversy concerning how well they work.


An international committee of experts summarized the existing research on the effectiveness of psychological treatment for sexual offenders. The committee examined 43 studies with a combined sample of 9,454 sexual offenders. Most of the studies examined mixed groups of child molesters and rapists, with an average 4 to 5 years of follow-up. The individual studies were coded according to the type of treatment provided and the research design used, and were then statistically combined (i.e., meta-analysis).


On average, sexual offenders who received treatment were less likely to reoffend than offenders who did not receive treatment. Not all treatments were equally effective. Treatments provided prior to 1980 appeared to have little effect. In contrast, current treatments were associated with a significant reduction in both sexual recidivism (from 17% to 10%) and general recidivism (51% to 32%).

The treatments that appeared effective were cognitive-behavioural treatments for adult sexual offenders, and systemic treatments for adolescent sexual offenders. Cognitive-behavioural treatments identify the habits, values and social influences that contribute to offending and teach offenders the self-management skills to cope effectively with high risk situations. Systemic treatments address the needs of the family and other social systems influencing young offenders, such as school, peers, and courts.

Treatment programs delivered in the community appeared to be equally effective to programs delivered in institutions. Offenders who failed to complete treatment were consistently higher risk to reoffend than offenders who completed treatment, regardless of the type of treatment they attended.

Although the results are encouraging, they should be interpreted cautiously given that there were few high quality research studies (e.g., random assignment). The treatment effects were not large, and the current results provide little direction concerning how to improve interventions with sexual offenders.

Policy implications

  1. Treatment programs can contribute to public safety by reducing the risk of reoffending among sexual offenders.
  2. Not all treatment programs are effective. Risk managers (such as parole decision makers) cannot assume that any treatment is better than no treatment. Before deciding that an offender's recidivism risk is reduced by treatment, evaluators need to consider the nature and quality of the treatment provided.
  3. Training and supervision efforts should focus on those treatments that have the strongest evidence for effectiveness, namely cognitive-behavioural treatments and systemic treatments.
  4. No treatment program can guarantee a complete cessation of offending. Consequently, treatment programs should be considered one element in a comprehensive risk management strategy.


For further information

R. Karl Hanson, Ph.D.
Public Safety Canada
340 Laurier Avenue West
Ottawa, Ontario
K1A 0P8
Tel 613-991-2840
Fax 613-990-8295

Date modified: