Do the Dark Triad and psychological intimate partner violence mutually reinforce each other? An examination from a four-wave longitudinal study

Although cross-sectional research showed a correlation between the Dark Triad and intimate partner violence (IPV), it was unclear whether the Dark Triad facilitated violence toward partners or whether violent acts fostered the dark personality traits . We aimed to statistically clarify the causal relationships between the Dark Triad traits and psychological IPV perpetration in romantic relationships. We conducted a longitudinal study every four months for one year across four waves in a sample of individuals who were currently in romantic relationships. A total of 1392 individuals ( M age = 29.73, SD age = 5.92) who dated the same partners throughout completed the four waves of surveys that measured the Dark Triad traits, psychological IPV, and demographic variables. Cross-lagged panel models revealed consistent patterns in the associations between each of the Dark Triad traits and psychological IPV perpetration throughout the four waves. Machiavellianism and psychological IPV perpetration increased each other. Psychological IPV perpetration reinforced the tendency for psychopathy , but not vice versa. Narcissism promoted future psychological IPV perpetration, but not vice versa. Our study illustrates how the Dark Triad traits accelerate psychological violence toward romantic partners and how such violence fosters the dark side of personality.