Frequency and Detection of Malingering in Homicide Defendants Undergoing Criminal Responsibility Evaluations Using the Schedule for Nonadaptive and Adaptive Personality: A Feasibility Study

Abstract

This retrospective study reports on (a) the prevalence of malingering in a sample of 20 homicide defendants seen in jail settings for criminal responsibility evaluations, and (b) the feasibility of the Schedule for Nonadaptive and Adaptive Personality (SNAP) for malingering detection in this sample. Based on previous non-clinical simulation research, it was hypothesized that the SNAP validity scales would predict group membership for homicide defendants malingering psychopathology. Those with intellectual disabilities or psychotic disorders were excluded. Diagnostically, nearly one half of the sample had Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR) personality and substance use disorders. Point prevalence of malingering was 30%. Using the criterion of any SNAP validity scale score in the clinical range (T ≥ 65), a reasonable sensitivity was demonstrated in the detection of malingering (83%), yet this outcome was hindered by a high false positive rate (64%). This study suggests further exploration of the SNAP for assessing malingering in forensic populations is warranted.