“If you’re not on our side, attack”… A person who clearly reveals their political inclination, is it ‘this’?

A study found that openly displaying content that disparages or offends politically opposing sides is linked to psychopathy, one of the dark triad traits.

The researchers explained that with political polarization and resulting out-group hostility increasing worldwide, it is important to understand what role individuals with dark personality traits play in current political tensions.

The Dark Triad, which this study focuses on, refers to the three major antisocial personality factors: Machiavellianism, psychopathy, and narcissism.

Researchers at Northwestern University’s Kellogg School of Management conducted two studies to achieve this goal. Both studies recruited participants through the online platform Prolific to obtain a diverse sample of the U.S. population.

The first study involved a survey of 299 participants. Participants were balanced in political affiliation (45% Democrat, 48% Republican), gender (76% female, 24% male), and ethnic background. The Dark Triad Dirty Dozen (DTDD) scale was used to measure the Dark Triad traits. This 12-item scale asks a variety of questions about each personality trait to determine a person’s personality.

Participants were then shown eight bumper stickers with messages insulting the political opposition and asked to rate their willingness to wear each sticker in public places on a seven-point scale. The stimuli were adjusted to ensure relevance based on the participants’ political leanings.

The second study built on the results of the first study with some improvements and extensions. This time, it assessed psychopathy and Machiavellianism using a different method than the DTDD scale, addressing concerns that the two concepts were confused in the previous scale. Participants evaluated products containing political messages, such as T-shirts, hats, and buttons, and reported their willingness to display them in various situations, including to members of their political ingroup (our group), to members of their outgroup, and in private.

As a result, consistent patterns emerged across the two studies. In the first study, psychopathy was the only one of the three personality traits that significantly predicted willingness to display bumper stickers. This finding was confirmed in the second study. Psychopathy was the strongest predictor of this tendency regardless of the context. Machiavellianism also showed some association, although weaker. Narcissism, on the other hand, was unrelated across all contexts.

“We found that psychopathy predicted a tendency to publicly display politically aggressive products toward both in-group and out-group members,” the researchers wrote. “While there are certainly social and political factors that contribute to polarized forms of expression, people’s underlying predispositions are also relevant.”

He continued, “The ultimate goal of this research is to understand why we are polarized and to develop interventions to address political polarization and the out-group hostility that it creates.” He added, “It is increasingly necessary to understand the social and dispositional factors that contribute to polarization, because while we may not agree with or dislike the views of others, in extreme cases it can undermine the foundations of a democratic society.”

On the other hand, the sample of this study was limited to U.S. residents, which raises questions about whether these results can be applied to other cultural contexts. Therefore, future research could aim to examine whether these patterns apply to other countries with widespread political tensions, and to examine other factors that may interact with personality traits to influence ideological tendencies.

The results of this study were published in the Journal of Research in Personality under the title, “The Dark Triad predicts public display of offensive political products.”