Psychopathy and Machiavellianism: A Distinction Without a Difference?

A robust literature has emerged on the Dark Triad (DT) of personality-Machiavellianism (MACH), psychopathy, and narcissism. Questions remain as to whether MACH and psychopathy are distinguishable and whether MACH's empirical and theoretical networks are consistent. In Study 1 (N = 393; MTurk research participants), factor analyses were used to compare two-factor (MACH and psychopathy combined + narcissism) and three-factor models, with both fitting the data equally well. In Studies 1 and 2 (N = 341; undergraduate research participants), DT scores were examined in relation to a variety of external criteria, including self- and informant ratings of personality, adverse developmental experiences, and psychopathological symptoms/behaviors. In both studies, MACH and psychopathy manifested nearly identical empirical profiles and both were significantly related to disinhibitory traits thought to be antithetical to MACH. In Study 3 (N = 36; expert raters), expert ratings of the Five-Factor Model traits prototypical of MACH were collected and compared with empirically derived profiles. Measures of MACH yielded profiles that were inconsistent with the prototypical expert-rated profile due to their positive relations with a broad spectrum of impulsivity-related traits. Ultimately, measures of psychopathy and MACH appear to be measuring the same construct, and MACH assessments fail to capture the construct as articulated in theoretical descriptions.