September 18, 2012

Assessing “volitional control” in sex offenders

When I review government reports in sexually violent predator cases, I find that most focus on two things: (1) the person's risk of future sexual violence, and (2) whether that risk is related to a psychiatric disorder.

But this misses a critical piece of the puzzle. In order for a civil commitment based on future danger to be Constitutional under Kansas v. Crane, the former sex offender must also demonstrate a serious difficulty controlling his behavior.

It's understandable that some evaluators shy away from addressing this issue of so-called "volitional control." After all, it is not easy to measure. Far easier to assume a circular tautology, in which a failure to control one's behavior is advanced as evidence of inability to exert self control. But, as the American Psychiatric Association famously noted in a 1983 statement opposing conclusory opinions on volitional control in insanity cases:

"The line between an irresistible impulse and an impulse not resisted is probably no sharper than that between twilight and dusk."

Into this breach jumps psychologist Frederick Winsmann of Boston. In an article in the current issue of Sex Offender Treatment, he proposes a model for how to assess volitional control in sexually violent predator evaluations.

Credit: The Bad Chemicals
Winsmann theorizes that poor self control emanates from two related processes: (1) behavioral impulsivity, and (2) impaired decision-making. He recommends that evaluators incorporate screening measures that tap into these two processes, such as the Barratt Impulsiveness Scale and tests of executive (frontal lobe) functioning like the Wisconsin Card Sorting Test or the Iowa Gambling Task.

While this approach is a welcome step in the right direction, it must be recognized that tests of impulsivity and frontal lobe functioning are just indirect measures of the volitional impairment that is theorized to underlie some sexual offending.

Indeed, Winsmann stresses that these tests should be approached as part of a larger idiographic framework of understanding the person as a unique individual, and that poor test performance does not in and of itself establish volitional impairment. For example, scores may be lowered by poor cognitive abilities. (I have also seen cognitively normal people with fine self control do poorly on the Wisconsin Card Sorting Test due to high anxiety.)

The full article is available for free online (HERE).