Post Hoc Reasoning in Possible Cases of Child Sexual Abuse: Symptoms of Inconclusive Origins.

Abstract

This article addresses the role of psychological expert testimony in possible cases of child sexual abuse (CSA). It describes the logical conditions that must be met in order to engage validly in post hoc reasoning from present symptoms experienced by a child to the conclusion that the child has or has not been sexually abused. The use of various stress and sexual abuse accommodation theories as support for these conclusions is examined. In addition, the practical problems of using Bayes’ Theorem to inform jurors in suspected cases of CSA are described, and an actuarial model of post hoc reasoning is proposed. Given the gaps in knowledge concerning the relevant probabilities and thus the differential probabilities of symptom/abuse versus symptom/no abuse, it is argued that it is not possible currently to reason from symptom observation at Time., to abuse status at Time,. The implications of this thesis are explored. Finally, the valuable forensic contributions that may be made by mental health experts in cases of alleged CSA are suggested.

A Comprehensive Guide to Child Custody Evaluations: Mental Health and Legal Perspectives

“…Recent reviews of the research literature have concluded that there are no psychological symptom markers for child sexual abuse (Sbraga & O'Donohue, 2003). Because there is no personality profile for victims of sexual abuse, no personality assessment devices can provide definitive evidence that sexual abuse has occurred (Weiner, 2005).…”

Strategies to Address Clinical Bias in the Child Custody Evaluation Process

“…A straightforward recommendation encountered through several sources on debiasing is that clinicians develop a firm understanding of basic Bayesian statistics, 2 especially in calculations involving base rates of phenomena (Arkes, 1981;Borum, Otto & Golding, 1993;Morrow & Deidan, 1992;Sbraga & O'Donohue, 2003). This recommendation stems from the long known issue of the difficulty for clinicians in predicting rare events from inexact data (Tversky & Kahneman, 1982b).…”

Rorschach Assessment in Child Custody Case

“…Beginning with Browne and Finkelhor (1986) and continuing to the present time, reviews of research have indicated that the experience of having been sexually abused can lead to a variety of psychological outcomes (Kendall-Tackett, Williams, & Finkelhor, 1993Merrill, Thomsen, Sinclair, Gold, & Milner, 2001;Rind, Tromovitch, & Bauserman, 1998;Sbraga & O'Donohue, 2003). These outcomes vary with the nature and circumstances of the abuse (e.g., at what age and persisting over what period of time, the prior relationship to the abuser, the extent to which the abuse was physical as well as sexual), and these outcomes include (but are not limited to) stress disorder, depression, sexual or interpersonal aversiveness, hypersexuality or promiscuity, and even no detectable psychological maladjustment.…”