Thank you.
A number of research projects have been undertaken by academia on the risks of recidivism by sex offenders. Actually, Canada is recognized as a leader in this field.
The ranges for reoffending really vary. In some cases, it's 13% for all types of sex offenders. For others, the risk of recidivism is up to 52% and 60%. It depends on what type of offender you are evaluating. For instance, certain child molesters have a high risk of recidivism, and so do rapists, but other types of offenders are less likely to reoffend.
The answer is very complicated and there are different reasons for that. I can tell you that most people involved in research will tell you that the rates are underestimated, simply because it's very hard to detect sexual crime. Very often, sexual crime is not reported to the police.