Sex offender recidivism refers to the commission of a subsequent offense by a sex offender on release. The base rates of sexual offending have been found to range anywhere from 4% to 71% across studies. Some research findings suggest that the risk of re-offending may differ according to the sex offender typology. Furthermore, there is some research that suggests that there are various static and dynamic risk variables that can increase the likelihood of re-offense. However, there has been a considerable amount of debate in the literature about how sex offender recidivism should be operationalized. These debates center on the definition of a subsequent re-offense, how to handle unreported crimes, and the duration of the follow-up period.
Sex Offender Recidivism
Although there have been numerous individual studies assessing recidivism rates of sex offenders, Hanson and his colleagues have conducted two seminal meta-analyses examining recidivism rates of sex offenders. In studying sex offender recidivism, meta-analyses are superior to individual studies as they can statistically combine results from several studies, thus increasing the generalizability of the findings.
Hanson and Bussiere conducted a meta-analysis of 61 recidivism studies, which provided information on 28,972 sexual offenders. They found that, on average, the sexual recidivism rate was 13.4% after between 4 and 5 years. When they examined sexual recidivism by the type of sex offender, they found a recidivism rate of 18.9% for rapists and 12.7% for child molesters. When they examined recidivism rates for nonsexual violent recidivism, they found an overall recidivism rate of 12.2%, with child molesters re-offending at a rate of 9.9% and rapists at 22.1%. Finally, when they defined re-offending as any re-offense (sexual, violent nonsexual, or nonviolent nonsexual), Hanson and Bussiere found an overall recidivism rate of 36.3%, with 36.9% for child molesters and 46.2% for rapists.
In 2005, Hanson and Bourgnon conducted another meta-analysis of 82 recidivism studies providing information on 29,450 sex offenders over an average of 5 to 6 years postrelease. This time they found an average sexual offense rate of 13.7%, a violent nonsexual re-offense rate of 14.3%, and a general (including sexual, violent nonsexual, or nonviolent nonsexual) re-offense rate of 36.2%.
Factors to Consider in Defining Sex Offender Recidivism
Factors such as the definition of recidivism, unreported sex crimes, and the length of follow-up can have an impact on the determination of recidivism rates.
The definition of what constitutes sexual recidivism is a hotly contested topic. While almost all researchers agree that recidivism should be defined as a subsequent offense, the nature of the re-offending has been contested. In some studies, recidivism is defined as a subsequent charge or arrest, while other studies specify that the subsequent charges or arrests must result in a conviction. Furthermore, some researchers argue that among sex offenders, recidivism should refer only to new sexually based crimes. However, other researchers define recidivism as any subsequent crime, regardless of its nature. Finally, some studies define recidivism as re-incarceration.
These differences in the operational definition of recidivism have serious implications when considering the prevalence of sex offender recidivism. For example, studies in which subsequent arrests were used as the criterion would result in higher recidivism rates because being arrested or charged with a crime does not always result in conviction. Operationalizing recidivism as subsequent re-incarceration makes the definition more narrow thus decreasing recidivism rates. However, some researchers would argue that sex offender recidivism should encompass reconviction only for sexually based crimes and not crimes that are nonsexual in nature. Finally, using subsequent re-incarceration as the criterion could also erroneously inflate recidivism statistics as many sex offenders have long periods of parole following the completion of their sentence, and they could be re-incarcerated for technical parole violations such as drinking alcohol or failing to meet with their parole officer. Therefore, it is very important when examining rates of sexual recidivism to determine how the researchers have operationalized recidivism.
Another issue to consider when examining rates of sexual recidivism is the number of sex crimes that go unreported or undetected. For example, it is estimated that only 32% (or 1 in 3) of sex crimes against individuals older than 12 are reported to the police. Polygraph studies of convicted sex offenders found that sex offenders had committed significantly more sexual offenses than they were charged or convicted of and that, on average, sex offenders had been committing crimes for 16 years before being caught.
Furthermore, even if an offender is charged with a sex crime, it may be harder to prove, so they may plead to a lesser nonsex crime.
Finally, when conceptualizing sex offender recidivism, it is also important to examine the length of the follow-up period. While recidivism may be considered to be a lifelong occurrence, many studies use discrete periods of 5 or 10 years postrelease, while some studies have followed sex offenders for up to 25 years. However, the duration of postincarceration follow-up could also influence recidivism rates as it is inevitable that the longer the follow-up period, the more likely it is that a sex offender will re-offend.
Static and Dynamic Predictors of Sex Offender Recidivism
Factors predicting risk for recidivism among sex offenders can be separated into static and dynamic risk variables. Static risk variables are risk factors that are unchangeable, such as age or ethnicity, while dynamic risk variables are factors that are amenable to change with treatment, such as anger.
In their 1998 meta-analysis, Hanson and Bussiere found several static variables that were related to sex offender recidivism. They categorized them into four broad domains encompassing criminal lifestyle, psychological maladjustment, sexual deviance, and treat-ment motivation. Of those general categories, they found that the strongest predictor of sexual recidivism was deviant sexual interest. Specifically, they found that offenders who had sexual interest in boys and those who had any other sort of deviant interest were more likely to re-offend sexually. Additionally, they found that offenders who were young (under the age of 25) and single (never having been in a long-term relationship) were more likely to re-offend. The risk for recidivism was also increased if the sex offender had a prior sexual offense, had victimized strangers, had an extrafamilial victim, started offending at an early age, had male victims, and had engaged in diverse sexual crimes. Finally, they found that offenders who had failed to complete treatment or those who were exhibitionists were more likely to have committed another sexual offense. These findings were used as the basis for the development of the STATIC-99, an actuarial risk assessment tool used to assess the risk for future sex offender recidivism.
In a subsequent meta-analysis of 82 recidivism studies, Hanson and Morton-Bourgnon found that sexual deviancy and antisocial orientation (composed of antisocial personality disorder, psychopathy, antisocial traits, and a history of rule violation) were the best predictors of sexual recidivism.
Few studies have focused on dynamic factors related to recidivism. In their meta-analysis, Hanson and Morton-Bourgnon found several dynamic factors that were related to sexual recidivism, including sexual preoccupation and general self-regulation deficits. However, it should be noted that they found no relationship between factors that have been commonly assumed to be related to sexual re-offending and subsequent sexual recidivism, such as psychological distress, denial of sex crimes, victim empathy, and motivation for treatment.
Hanson and Harris conducted another study looking specifically at dynamic factors related to sexual recidivism. They examined sexual re-offending in a sample of 400 sex offenders for a period of 5 years following release. The researchers found that sex offenders who had committed new sex crimes were more likely to be unemployed, have substance use disorders, engage in deviant sexual activities, demonstrate low levels of remorse for the victim, and report a more chaotic and antisocial lifestyle than those who had not committed new sexual offenses.
Sex Offender Typologies and Recidivism
Some evidence suggests that the risk of sexual recidivism may differ by sex offender typology (category of sex offender). One study found that rates of sexual re-offense for incest offenders (those who offend against family members) ranged between 4% and 10%; rates of sexual recidivism for child molesters with female victims ranged between 10% and 29%; rates of sexual recidivism for child molesters with male victims ranged between 13% and 40%; rates of sexual recidivism for rapists ranged between 7% and 35%; and rates of sexual recidivism for exhibitionists (those who expose themselves in public) ranged between 41% and 71%.
Numerous studies have examined recidivism rates for rapists. Rates of sexual recidivism for rapists have ranged between 11% and 28% over 5 years. Researchers have postulated that these discrepancies in recidivism rates could be attributed to the fact that there are different types of rapists (such as those who are mentally disordered vs. those on probation) and the differential length of follow-up.
When studying recidivism rates among sex offenders who commit sexual offenses against children, researchers generally separate the sex offenders into three categories: (1) those who molest girls; (2) those who molest boys; and (3) those who molest family members (incest offenders). Generally, it has been found that child molesters who have same-sex victims are at risk of higher rates of re-offending than those who offend against children of a different sex. A study of mentally disordered child molesters who offended against boys found a recidivism rate of 30% over 5 years, compared with a 25% recidivism rate for child molesters who offended against girls and a recidivism rate of 6% for incest offenders. However, other studies have found no differences between recidivism rates for child molesters with male or female victims.
It should be noted that there have been some contradictory findings regarding sex offender typologies and risk for re-offending in the recidivism literature. Many studies, including Hanson and Bussiere’s meta-analysis, have found higher sexual recidivism rates for rapists compared with child molesters, with incest offenders having the lowest rate of re-offense of all categories of sex offenders. However, one study found that over a 25-year period, child molesters had a higher rate of re-offense than rapists (52% vs. 39%). In this study, recidivism was recorded as any new re-arrest that could inflate recidivism statistics. Another factor that should be considered when examining sex offender typologies and recidivism is that there is some evidence that sex offenders may not be stable in their victim choice, and there could be crossover (e.g., a child molester with male victims could offend against a female) in victim age and gender.
- Hanson, R. K., & Bussiere, M. T. (1998). Predicting relapse: A meta-analysis of sexual offender recidivism studies. Journal of Consulting and Clinical Psychology, 66(2), 348-362.
- Hanson, R. K., & Harris, A. (2000). Where should we intervene? Dynamic predictors of sexual offense recidivism. Criminal Justice and Behavior, 27(1), 6-35.
- Hanson, R. K., & Morton-Bourgnon, K. E. (2005). The characteristics of persistent sexual offenders: A meta-analysis of recidivism studies. Journal of Consulting and Clinical Psychology, 73(6), 1154-1163.
- Marshall, L., & Barbaree, H. E. (1990). Outcomes of comprehensive cognitive-behavioral treatment programs. In W. L. Marshall, D. R. Laws, & H. E. Barbaree (Eds.), Handbook of sexual assault: Issues, theories, and treatment of the offender (pp. 363-385). New York: Plenum.
- Prentky, R., Lee, A., Knight, R., & Cerce, D. (1997). Recidivism rates among child molesters and rapists: A methodological analysis. Law and Human Behavior, 21, 635-659.