By Karen Franklin, Ph.D.
It would be humorous if the real-world consequences were not so grave.
Every year, at a jam-packed session of the annual conference of the Association for the Treatment of Sexual Abusers (ATSA), the developers of the Static-99 family of actuarial risk assessment tools roll out yet a new methodology to replace the old.
This year, they announced that they are scrapping two of three sets of "non-routine" comparison norms that they introduced at an ATSA conference just four years ago. Stay tuned, they told their rapt audience, for further instructions on how to choose between the two remaining sets of norms.
To many, this might sound dry and technical. But in the courtroom trenches, sexually violent predator cases often hinge on an evaluator's choice of a comparison group. Should the offender be compared with the full population of convicted sex offenders? Or a subset labeled "high risk/needs" that offended at a rate more than 3.5 times higher than the more representative group (21 percent versus 6 percent after five years)?
To illustrate, whereas only about 3 percent (4 out of 139) of the men over 70 in the combined Static-99R samples reoffended, invoking the high-risk norms would cause a septuagenarian's risk to skyrocket by 400 percent. It's not hard to see why such an inflated estimate might increase the odds of a judge or jury finding a former offender to be dangerous, and recommending indefinite detention.
The first problem with this method is that the basis for choosing a comparison group is very vague, inviting bias on the part of forensic evaluators. Even more essentially, there is not a shred of empirical evidence that choosing the high-risk norms improves decision-making accuracy in sexually violent predator (SVP) cases.
That should come as no surprise. Not one of the six samples that were cobbled together post-hoc to create the high-risk norms included anyone who was civilly committed -- or considered for commitment -- under modern-day SVP laws, which now exist in 20 U.S. states. (Four samples are Canadian, one is Danish, and the only American one is an exceptionally high-risk, archaic and idiosyncratic sample from an infamous psychiatric facility in Bridgewater, Massachusetts.)
A typical psychological test has a published manual that gives instructions on proper use and clearly describes its norms. In contrast, the Static-99, despite its high-stakes deployment, has no published manual. Its users must rely on a website, periodic conferences and training sessions, and word-of-mouth information.