Olver, M. E., Sowden, J. N., Kingston, D. A., Nicholaichuk, T. P.,
Gordon, A., Beggs Christofferson, S. M., & Wong, S. C. P. (2016).
Predictive accuracy of Violence Risk Scale-Sexual Offender version risk and
change scores in treated Canadian Aboriginal and non-Aboriginal sexual
offenders. Sexual Abuse: A Journal of Research and Treatment.
Abstract: The present study examined the predictive properties of
Violence Risk Scale–Sexual Offender version (VRS-SO) risk and change scores
among Aboriginal and non-Aboriginal sexual offenders in a combined sample of
1,063 Canadian federally incarcerated men. All men participated in sexual
offender treatment programming through the Correctional Service of Canada (CSC)
at sites across its five regions. The Static-99R was also examined for
comparison purposes. In total, 393 of the men were identified as Aboriginal
(i.e., First Nations, Métis, Circumpolar) while 670 were non-Aboriginal and
primarily White. Aboriginal men scored significantly higher on the Static-99R
and VRS-SO and had higher rates of sexual and violent recidivism; however,
there were no significant differences between Aboriginal and non-Aboriginal
groups on treatment change with both groups demonstrating close to a
half-standard deviation of change pre and post treatment. VRS-SO risk and
change scores significantly predicted sexual and violent recidivism over fixed
5- and 10-year follow-ups for both racial/ancestral groups. Cox regression
survival analyses also demonstrated positive treatment changes to be significantly
associated with reductions in sexual and violent recidivism among Aboriginal
and non-Aboriginal men after controlling baseline risk. A series of follow-up
Cox regression analyses demonstrated that risk and change score information
accounted for much of the observed differences between Aboriginal and
non-Aboriginal men in rates of sexual recidivism; however, marked group
differences persisted in rates of general violent recidivism even after
controlling for these covariates. The results support the predictive properties
of VRS-SO risk and change scores with treated Canadian Aboriginal sexual
offenders.
The full article is available via open access from:
Could you talk us through where the idea for the research came from?
The idea for the
research came from a recent Canadian legal decision, Ewert v. Canada, that came
out in September 2015. The plaintiff, a man of Métis descent, who had been in
custody for more than 30 years on murder and attempted murder (both sexually
motivated offenses) had sued the federal government with the contention that
actuarial risk assessment tools, and other certain forensic measures, were biased
against individuals of Aboriginal ancestry and that he had been caused harm
through their use in his case. The tools identified were the Violence Risk
Scale-Sexual Offender version (VRS-SO), Static-99, Violence Risk Appraisal
Guide, Sex Offender Risk Appraisal Guide, and the Psychopathy
Checklist-Revised. In his decision, Justice Phelan ruled that the evidence
accumulated thus far had not been sufficient to justify their applications to
offenders of Aboriginal descent and strongly cautioned the Correctional Service
of Canada (CSC) against using these and related tools with this population
until further research supporting their psychometric properties with Aboriginal
persons had been conducted. Given the overrepresentation of Aboriginal persons
in Canadian corrections, for some time we wished to do such research examining
the psychometric properties of the VRS-SO with this population but we didn’t
have the sample size to do so. Justice Phelan’s decision was an important call
for research and by the time the decision was released we had accumulated
sufficient numbers across three CSC-based studies of treated sex offenders to
do the work. The decision thus provided an extremely powerful impetus for our
group to examine the predictive properties of VRS-SO risk and change scores
with Aboriginal offenders.
What kinds of challenges did you face throughout the process?
The decision had issued
a challenge to the federal government specifically and to researchers outside
the service more generally who may have capacity to explore these questions;
but a follow-up decision had yet to be made about whether there may be a formal
prohibition issued concerning the use of these tools with Aboriginal offenders
in federal corrections. One key issue was time, as my co-authors and I were
hoping that the results may assist future decisions on this matter, but it was
uncertain when that would be or what the results would be. So I made a mad dash
to obtain IRB approval to link the data sets and to conduct these Aboriginal analyses,
to do the actual work involved, and then ultimately to get the word out as
quickly as possible when we had a good understanding about the findings. As it
turns out, a remedy hearing was held the last week of April 2016 to speak to
the issues and concerns raised by the judge and to examine future research
directions on these tools with Aboriginal offenders. I had the privilege of
appearing as an expert witness to give testimony on post-trial research and use
of these tools with Aboriginal offenders. The manuscript had been accepted for
publication in SAJRT just the week prior to me appearing in court.
What kinds of things did you learn about co-authorship as a result of
producing this article?
I have a great team of
colleagues who have contributed data, resources, and ideas to support the
validation of the VRS-SO. The authorship list, which features a diverse group
of VRS-SO contributors is as much a statement of support for the findings
generated and the use of the tool to assess risk, identify treatment needs, and
track change with adult male Aboriginal sex offenders.
What do you believe to be to be the main things that you have learnt
about Aboriginal sex offenders and/or Risk Assessment?
The results are
consistent with past research showing that structured risk assessment tools can
predict recidivism outcomes with Aboriginal offenders; in essence the tools do
work with Aboriginal offenders. That the predictive accuracy magnitudes were consistently
slightly lower for Aboriginal offenders is also consistent with available
research. The higher recidivism base rates we see with Aboriginal offenders,
however, do not align neatly with the higher risk scores they also receive;
base rates can be impacted by other unmeasured variables and identifying these
variables is an extremely important area of ongoing research. Perhaps the most
encouraging finding for us was to see that the men across ancestral groups made
broadly the same amounts of change from sex offender treatment, and these
changes showed similar magnitudes in predicting decreased sexual and violent
recidivism. The results highlighted to us that a structured dynamic tool, such
as the VRS-SO, that can track and measure change can actually be used to help
these men in their commitments and efforts to lower their sexual reoffending
risk in preparation for reintegration back into the community.
Now that you’ve published the article, what are some implications for
practitioners?
The results support the
appropriate use of the VRS-SO and the Static-99R with men of Aboriginal
ancestry to assess risk, inform treatment programming, and to evaluate changes
in risk. Any assessment also needs to take into consideration unique cultural,
situational, personal, and historical background factors to contextualize
conclusions and risk management recommendations.
Mark Olver, PhD
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