The self-concepts of people with Dark Triad traits tend to be weaker, less clearly defined, and more state-related

Researchers have examined overt social-behavioral manifestations of Dark Triad traits, while mostly ignoring the similarities in the covert self-concept of these individuals. Across two independent samples, we investigated aspects of an unstable self-concept in relation to the Dark Triad traits. In Study 1 (N = 298), we found that higher levels of the Dark Triad traits were related to a weaker sense of self, decreased trait-term usage, and greater state-term usage in a spontaneous self-concept task. In Study 2 (N = 262), we sought to obtain a more fine-grained understanding of these associations. In regression models, secondary psychopathy followed by vulnerable narcissism emerged as the only predictors of both a weaker sense of self and lower self-concept clarity, whereas the Leadership/Authority aspect of grandiose narcissism emerged as a significant predictor of a stronger sense of self and increased self-concept. These findings are discussed within the context of existing theory (i.e., the life strategy approach and the Vulnerable Dark Triad model). •Dark Triad traits predicted a weaker and more unstable sense of self.•Dark Triad traits were related to more state- and less trait-related self-concepts.•Secondary psychopathy was the strongest predictor of a weaker and unstable self.•Leadership/Authority was the only predictor of a stronger sense of self.