All the truly bad people you know share this personality trait

With Supreme Court nominee Brett Kavanaugh and Bill Cosby making headlines this week—both regarding issues of sexual assault (Kavanaugh’s alleged, Cosby’s convicted)—it’s probable you’ve heard at least one person mutter, “What an awful person.” These men have become two of the most hated people in America, and new research shows there’s a scientific reason why it seems like they share a key personality trait: the ability to pursue their own interests singularly, without regard for others.

According to the results of a series of studies (that included more than 2,500 participants) published in the journal Psychological Review, researchers have discerned a common thread shared by those who have dark personality traits (including narcissism, psychopathy, egoism, sadism, self-interest, and spitefulness). This “dark core” or D-factor, as the authors are calling it, is defined in the paper as “the general tendency to maximize one’s individual utility—disregarding, accepting, or malevolently provoking disutility for others—accompanied by beliefs that serve as justifications.” Which translates to, being selfish without giving a s**t, to the extent that you might even hurt people for fun.

“The D-factor indicates how likely a person is to engage in behavior associated with one or more of these dark traits.” —Ingo Zettler, professor of psychology

“The D-factor indicates how likely a person is to engage in behavior associated with one or more of these dark traits [narcissism, et al.],” said study author Ingo Zettler, professor of psychology at the University of Copenhagen, in a press release. And if a person is prone to one nasty behavior—say, lying—they’re also more prone to other nasty behaviors, like making fun of people or stealing.

According to Zettler, knowledge about someone’s D-factor could be incredibly useful, helping professionals “assess the likelihood that the person will reoffend or engage in more harmful behavior,” he says. But outside of the office, it’s easy to see how this could be useful, too—you know, when doing things like dating or choosing elected officials.

Here’s exactly how to heal after dating a narcissist or sociopath. Or, find out the psychological reason why you’re attracted to bad guys.