Contributions of the dark triad to moral disengagement among incarcerated and community adults

Previous research has revealed a strong association between moral disengagement (MD) and criminal behaviour. However, few studies have attempted to examine the contribution of dark personalities to MD. This study aims to first analyse the differences between forensic and community samples in the use of MD strategies and then replicate the factorial structure of the Dark Triad Dirty Dozen scale in an incarcerated sample as a pre-condition to examine the relationship between dark triad (DT) traits (i.e. Machiavellianism, psychopathy and narcissism) and MD. The sample comprised 160 incarcerated and 160 community adults. Comparisons between these two groups demonstrate that the incarcerated sample scored higher in MD and DT than the community sample. Furthermore, different MD strategies were related to each of the DT traits in the forensic and community samples. The results of exploratory factor analysis for the incarcerated sample indicate adequate fit indices for a bifactorial model of the DT (a latent factor of the shared variance of these constructs named the global DT and three specific latent factors for each component of the DT). The SEM analysis for this bifactorial model and MD disclosed direct and significant relationships between the global DT and MD in the incarcerated adults, while the Machiavellianism factor was directly and significantly related to MD in the community adults. These results highlight the relevance of cognitive (i.e. MD) strategies in forensic contexts, especially in incarcerated adults who present high levels of this DT profile.