Virginia adopted a risk assessment to help determine sentencing for sex offenders. It was incorporated as a one-way ratchet toward higher sentences: expanding the upper end of the sentence guidelines by up to 300 per cent. This led to a sharp increase in sentences for those convicted of sexual assault. More surprisingly, it also led to a decrease in sentences for those convicted of rape. This raises two questions: (a) why did sentencing patterns change differently across these groups, and (b) why would risk assessment lead to a reduction in sentence length? The first question is relatively easy to answer. While both groups saw an expansion in the upper end of the sentencing guidelines, only sexual assault had the floor lifted on the lower end, making leniency more costly. The second question is less straightforward. One potential explanation is that the risk assessment served as a political or moral shield that implicitly justified leniency for those in the lowest risk category. Even though the risk assessment did not change sentencing recommendations for low-risk individuals, it provided a 'second opinion' that could mitigate blame or guilt should the low-risk offender go on to reoffend. This decreased the risks of leniency and counterbalanced any increase in severity for high-risk individuals.

Jennifer L. Doleac & Megan T. Stevenson, The Counterintuitive Consequences of Sex Offender Risk Assessment at Sentencing, 73 University of Toronto Law Journal, 59–72 (2023).