The effects of examiner personality variables and training on the accuracy of detection of deception

Conventional wisdom and qualitative research in the field of credibility assessment suggest that personality dimensions and training account for differences in job performance (DACA, 2006; DACA, 2007). However, to date, there has been a paucity of empirical research to further validate such qualitative findings. The present research seeks to explore the relationship between personality dimensions, training and job performance of polygraph examiners. Specifically, job performance is operationalized in two ways – firstly, the accuracy of examiners ability to detect deception via the evaluation of psychophysiological data related to detection of deception (i.e. polygraph chart data analysis) and secondly, the accuracy of examiners to detect deception via the analysis of verbal and nonverbal behavioral cues. Three studies were undertaken to investigate research question on examiner personality variables, training and performance. Study 1 adopted a competency modeling framework based on a survey of an expert panel. Topic experts in the field of credibility assessment in US federal and law enforcement agencies were surveyed to identify personality variables of interest. Data obtained from topic experts revealed that Openness to Experience, Conscientiousness, cognitive style Field Dependence Independence, Achievement motive, Power motive and Emotional Intelligence are possible predictors of polygraph examiner performance. Personality variables identified in Study 1 were modeled in Study 2 based on an experimental design. The model developed in Study 2 was replicated in Study 3 based on a sample comprising US and Singapore professionally trained polygraph examiners. Study 2 utilized an experimental design based on a NTU student sample who were assigned to two experimental groups, Trained and Not Trained groups. Participants in the Trained groups were provided information and feedback on methods of evaluating polygraph charts while participants in the Not Trained group were only provided information on polygraph chart evaluation. Trait dimensions Openness to Experience, Conscientiousness, implicit motive Achievement, cognitive style Field Dependence Independence and a theoretically derived interaction variable (i.e. interaction of Conscientiousness and implicit motive Achievement) were modeled as predictor variables of performance dimension of polygraph chart evaluation. While no training effects were noted in Study 2, personality trait dimension of Conscientiousness and implicit motive Achievement were found to be predictors of accuracy of polygraph chart analysis. Study results provided support to channeling hypothesis which is a postulation that implicit motives are channeled through motive supportive trait dispositions (Lang, Ewen, Hulsheger & Zettler, 2012; Winter, John, Stewart, Klohnen and Duncan, 1998). Study 3 modeled Study 2 variables as predictors of professional polygraph examiner performance in detection of deception using two modalities of detection of deception; polygraph chart analysis and verbal and nonverbal analysis based on the Forensic Assessment and Interview Technique (FAINT). Study 3 participants comprised Advanced trained polygraph examiners, Basic trained examiner and Novice or untrained examiners. Study 3 findings were premised on between and within subject designs were mixed. Between subject study provided data suggesting that detection of deception training places a strong emphasis on detection of deception cues (i.e. basic training orientates examiners towards a lie bias) and that this bias is corrected as they gain professional advanced training. The within-subject study provided data suggesting that detection of deception training places a strong emphasis on detection of truthful cues (i.e. basic training orientates examiners towards a truth bias). Personality dimension cognitive style Field Dependence Independence was found to be a predictor of accuracy of detection of countermeasure cases. In addition, Study 3 investigated the effects of detection of deception by behavioral analysis. This study provided data that trait dimension Agreeableness is a negative predictor and that implicit motive Affiliation and Emotional Intelligence- Perceive and Understand are predictors of detection of deception by verbal and nonverbal analysis. Study 3 results based on FAINT analysis suggest that detection of truthfulness is a more complex task than detection of deceit premised on finding that personality dimensions of Agreeableness, implicit motive Affiliation, and Emotional Intelligence facet Perceive and Understand were predictors of truthful cues but not for detection of deceit. It is possible that leakage of tell-tale physiological and behavioral signs related to a truthful subject is perhaps less due to less internal physiological, emotional and cognitive responses of deception, thus requiring more sensitivity in detection of said cues. Considered together, Study 3 suggest that examiner personality dimensions and training are important predictors of accuracy of detection of deception.Doctor of Philosophy (HSS