Psychopaths have long been characterized as having a remarkable disregard for the truth, to the extent that deceit is often regarded as a defining characteristic of the syndrome. Scholars described heightened concerns about how psychopaths’ deceitful and manipulative nature could significantly obstruct evaluations of psychopathy. The accurate evaluation of psychopathy is very important in forensic and correctional settings, and in such issues as risk assessment or dangerousness. Although the PCL-R is considered the quasi-gold standard when it comes to evaluating psychopathy, self-report measures have become more widely available and researched. Very few studies specifically evaluated response styles and self-report psychopathy measures despite the significant concerns regarding psychopathy and deception. The current study evaluated the ability of inmates with different levels of psychopathy to successfully engage in positive impression management on the SRP-4, LSRP, and PPI-R. Utilizing a repeated-measures, within-subjects design, 78 male inmates completed the study under genuine and simulation conditions. Overall, inmates were able to significantly lower their scores on all three self-report measures and achieved scores equivalent to and even lower than college and community samples. Inmates with higher levels of psychopathy were able to achieve larger decreases in scores on the PPI-R and on several scales for each measure. Another key finding was the identification of promising PPI-R Virtuous Responding Scale cut scores that can be utilized within forensic populations. Results indicate self-report measures should not be used to replace the PCL-R or comprehensive assessment of psychopathy in forensic evaluations; however, they do provide additional useful information and may be beneficial in other clinical settings.

Psychological assessment relies on accurate and forthright reporting to determine valid clinical presentations. However, it has long been recognized that examinees may be motivated to present a "better picture" through Positive Impression Management (PIM). Within the PIM domain, two distinct motivations (i.e., defensiveness and social desirability) emerge that have not been clearly differentiated in empirical literature. This thesis addressed the research gap for detecting PIM distortion of personality pathology, utilizing the Personality Inventory for DSM-5 (PID-5). In this investigation, 106 psychiatric inpatients were recruited from the adult Co-Occurring Disorders and Trauma Programs at University Behavioral Health. Using a mixed within- and between-subjects design, participants engaged in simulation via scenarios to be considered for a highly valued rehabilitation program (defensiveness) or employment (social desirability). As expected, inpatients showed elevated levels of problematic personality traits when reporting genuinely, but suppressed them under PIM conditions. These findings highlight that the PID-5, like all multiscale inventories, is highly vulnerable to intentional PIM distortion. Interestingly, respondents in the social desirability condition generally engaged in more total denial than those in the defensiveness condition. Empirically- and theoretically-based validity scales were developed to identify simulators and differentiate between conditions. Besides PIM, higher levels of experienced stigma were associated with more personality pathology, particularly the domain of Detachment. In addition, ancillary analyses showed strong convergence of the PID-5 with its hierarchical trait model to the DSM-IV categorical model. Continued research to detect PIM distortion, and more importantly to differentiate between PIM motivations, is essential for accurate clinical assessment of personality disorder traits and effective treatment planning.