Those who excel at manipulation often share certain personality traits. Narcissism, Machiavellianism, and psychopathy — a group of traits known as the dark triad — are common among master manipulators. These people may be charming and persuasive in face-to-face interactions, but a new study suggests these smooth talkers aren’t so convincing from behind a computer screen.

“The results of this study are pretty clear — once you remove non-verbal cues such as body language from the equation, the ability to smoke out narcissists and psychopaths becomes easier,” said Michael Woodworth, a professor of psychology at University of British Columbia Okanagan, in a press release. “We can also conclude that it is very likely that the qualities that allow these people to successfully charm, manipulate, intimidate, or exploit others appear to require a live, in-person audience.”

The research, which was conducted between October 2013 and February 2014, included more than 200 students from Canadian universities, all of whom were assessed on their dark triad qualities. Scientists randomly assigned the students to either a face-to-face or computer-mediated negotiation for event tickets as either a buyer or seller. The ultimate goal for students was to negotiate maximum financial benefit for themselves.

Woodworth’s study, titled “The Dark Side of Negotiation,” found that those who ranked higher on the Dark Triad spectrum were much more successful in face-to-face negotiations than they were online, which is consistent with research detailing the importance of body language in making deals. Surprisingly, however, high-ranking dark triad participants were 12.5 percent less successful in online negotiations than those ranking lower on the spectrum.

“While there has long been a fascination with dark triad personalities and how they can impact ‘ordinary’ people, little has been studied as to how these people behave online,” Woodworth said. “What this research tells us is that if you want to be confident in your ability to not be taken in by these types of known manipulators, you’re probably better off dealing with them online.”

Dark triad personalities get a bad rap for being sneaky and manipulative, and for good reason. Each of the three parts has distinct traits, many of which make manipulation easy. Psychopaths lack empathy, narcissists tend toward grandiosity and selfishness, and those with Machiavellian characteristics are goal-oriented and adept at calculating how to get what they want. Previous research has linked the triad to perfectionism, and suggested that men exhibiting these traits may actually be more successful reproductively.

Woodworth and honors student Lisa Crossley, who also worked on the study, are now conducting more research on dark triad personalities, this time looking at their powers of deception.

Source: Crossley L, Woodworth M, Black P, Hare R. The dark side of negotiation: examining the outcomes of face-to-face and computer mediated negotiations among dark personalities. Personality and Individual Differences. 2016.