Sex crimes more common in certain families

New research from Sweden's Karolinska Institutet in collaboration with Oxford University, UK, shows that close relatives of men convicted of sexual offences commit similar offences themselves more frequently than comparison subjects. This is due to genetic factors rather than shared family environment. The study includes all men convicted of sex crime in Sweden during 37 years.

"Importantly, this does not imply that sons or brothers of inevitably become offenders too", says Niklas Langstrom, Professor of Psychiatric Epidemiology at Karolinska Institutet and the study's lead author. "But although sex crime convictions are relatively few overall, our study shows that the family risk increase is substantial. Preventive treatment for families at risk could possibly reduce the number of future victims."

The report is published in the International Journal of Epidemiology and based on anonymised data from the nationwide Swedish crime and multigeneration registers.The research included all 21,566 men convicted for sex offences in Sweden between 1973 and 2009, for example rape of an adult (6,131 offenders) and child molestation (4,465 offenders). The researchers looked at the share of sex crimes perpetrated by fathers and brothers of convicted male sex offenders and compared this to the proportion among comparison men from the with similar age and family relationships.

The results suggested familial clustering of sex offenders, about 2.5 percent of brothers or sons of convicted offenders are themselves convicted for sex crimes. The equivalent figure for men in the general population is about 0.5 percent. Using a well-established statistical calculation model, the researchers also analysed the importance of genetic and environmental factors for the risk of being convicted of sexual abuse.

"We found that sex crimes mainly depended on and environmental factors that family members do not share with one another, corresponding to about 40 percent and 58 percent, respectively", says Niklas Langstrom. "Such factors could include emotional lability and aggression, pro-criminal thinking, deviant sexual preferences and preoccupation with ."

Self-reported sexual victimization rates in Sweden are largely similar to those in other Western and central European nations, Canada and the USA. Other cross-national comparisons of police-reported offences should be done cautiously because of differences in legal definitions, methods of offence counting and recording, and low and varying reporting rates of sexual violence to the police.

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More information: 'Sexual offending runs in families: A 37-year nationwide study', Niklas Langstrom, Kelly M. Babchishin, Seena Fazel, Paul Lichtenstein & Thomas Frisell, International Journal of Epidemiology, online 9 April 2015.
Citation: Sex crimes more common in certain families (2015, April 8) retrieved 24 August 2019 from
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Apr 09, 2015
Wow! Sounds like rehashed Eugenics to me. Hasn't humanity learned anything?

Apr 09, 2015
Wow! Sounds like rehashed Eugenics to me. Hasn't humanity learned anything?

Eugenics is the practice of deciding how desirable genetically influenced traits are AND discouraging people who carry those genes from passing them on. All the authors of this paper have done is state that a trait has a genetic component. They haven't suggested reducing the frequency of those genes by influencing anyone's reproductive choices, unless you think you should include within your definition of eugenics reducing the number of future victims, and by implication the offspring fathered by male sex offenders against the will of their victims. If you do think that is eugenics, do you really think humanity will benefit from not restricting that particular reproductive choice? Do you think the victims don't deserve a choice?

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