Paraphilias: Incidence and Co-occurrence in Normative and Sex Offender Samples

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Key Words

Life imprisonment, Lifers, Dangerous Offenders, CSC Offender Population Trends, department of corrections, corrections, prison, parole, sentencing, offenders, inmates, criminals, prisoners, prisons, penitentiaries, crime, justice, law, offender rehabilitation, security, corcan, inmates, incarceration

Why we did this study

For sexual offenders the presence of paraphilias is associated with increased risk of sexual recidivism. However, there are no studies that compile what is known about the presence of paraphilias in non-criminal and sexual offender samples. For clinicians, it is not known how likely a sexual offender is to have additional paraphilias beyond the one that brought him to the clinician’s attention. This paper is the first attempt to organize what information is known about co-occurring paraphilias based on past independent research.

What we did

Electronic databases were searched for published scientific papers that included data on the incidence and prevalence of paraphilias in both non-criminal and sex offender samples. This search resulted in 14 samples, five of which included data on non-criminals, 11 of which had data on sexual offenders, and one having data on sexually motivated murderers. The results from these samples were then compiled into tables showing the types of data collection strategies used and the range of responses across different samples. Tables were created that show, for example, how often a voyeur is likely to have additional paraphilias as opposed to an exhibitionist or a child molester.

What we found

Paraphilias occur in samples of non-criminals, but at much lower rates than in sexual offender samples. The presence of paraphilias and hypersexuality are related to higher risk for sexual recidivism in sexual offenders. A review of the literature suggests that the presence and persistence of paraphilias is likely to escalate over time. The detection of more common paraphilias (voyeurism, exhibitionism) in sexual offenders should cue clinicians to probe for further paraphilic interests. The data indicate that where one paraphilia is detected, in sexual offender samples, another paraphilia is likely present. The development of a standardized protocol to assess paraphilias over time may add to the ability to detect increasing risk for serious sexual recidivism.

What it means

This report highlights two key findings; first that the existing data likely underestimate the prevelance of paraphilias and co-occurring paraphilias and secondly, that, if you ask sexual offenders about paraphilic fantasies or behaviour, they will quite often respond candidly. If the risk for serious sexual recidivism increases as paraphilias escalate, the monitoring of paraphilias over time may provide clinicians with a metric to assess increasing dynamic risk. These data may inform more sophisticated risk assessments in the future as clinicians strive to develop a standardized method of assessing paraphilias and address the relationship between paraphilias and the risk of serious sexual recidivism. This study has many limitations due to the age of the studies, the overlap in samples reported by investigators, and the use of primarily self-report methodologies.

For more information

Harris, A. J. R.  (2011). Paraphilias: Incidence and Co-occurrence in Normative and Sex Offender Samples.  Research Report R-235.Ottawa (ON): Correctional Service Canada.

To obtain a PDF version of the full report, contact the following address:

Prepared by: Andrew J. R. Harris


Research Branch
(613) 995-3975