Past research found various immoral conducts that people with higher levels
of the Dark Triad traits are more inclined to engage in, including
infidelity. Marital dissatisfaction has also emerged as a factor of
unfaithful behaviors. However, the psychological dynamics of the effects of
these personality and relational factors on infidelity are less clear. This
study examined the potential mediational role of the use of moral
disengagement strategies for justifying infidelity in the relationships
between the Dark Triad traits and marital satisfaction, on the one hand, and
the tendency towards unfaithful behaviors, on the other, in married
participants (N = 241). Results indicate that psychopathy, narcissism and
marital dissatisfaction are related to stronger tendencies towards
infidelity, and that these effects are partially (in the case of psychopathy
and marital dissatisfaction) or totally (in the case of narcissism) mediated
by the tendency to morally justify unfaithful acts. No unique direct or
indirect effect of Machiavellianism emerged as significant, while men were
found to be more inclined towards unfaithful conduct. These findings
highlight the importance of the skewed and self-lenient moral judgments
fostered by the Dark Triad traits and marital dissatisfaction, which
legitimize one?s infidelity and thus renders it more likely.