You can tell someone is a psychopath by looking at just one part of them, according to psychologist

There are many of us who may wonder if someone we know is a psychopath. Unfortunately, those who are can do a very good job of hiding it.

But according to one psychologist, there's a way you may be able to tell - and it's both surprising and illuminating.

Susan Krauss Whitbourne, a former professor of psychological and brain sciences at the University of Massachusetts Amherst, has discussed psychopathic traits in articles in Psychology Today - and whether or not being in a relationship with a psychopath is bad for you.

The professor claims that research has proven the disturbing theory true - that you’ll be able to spot a psychopath a mile off, as it deals with the poses they make.

McGill University in Canada carried out a study with 608 adults, which found a common denominator between personality traits associated with psychopathic tendencies when asked to strike different poses.

Susan Krauss Whitbourne claims you may be able to tell if someone is a psychopath by looking at them (YouTube/American Psychological Association)

While no test will be able to tell you exactly what's circulating in someone's head, the professor said this one has clues.

The research found that a person holding an open or a large pose was more likely to try to take advantage of you, and those who were more extravagant scored higher for traits of 'psychopathy, manipulativeness, competitiveness, and belief in the existence of social hierarchies'.

On the other side of the coin, those who slouch or change their stance multiple times quickly were found to have lower self-esteem.

Another revelation was that those who had a straight spine were more likely to have a poor personality.

Whitbourne wrote: "To sum up, the McGill study provides a striking example of the link between body and mind, and ways you can use a person’s bodily cues to understand their mind."

Could you spot a psychopath? (Paramount Pictures)

It’s hard to know if someone really is a psychopath, as only the licensed criteria can prove that, but it’s good to know what the traits are to steer clear of people who could be bad for your life.

But is being in a relationship with someone with a high level of psychopathy truly bad for you?

'Unintended benefits'

In September this year, Whitbourne revisited the notion of psychopathy in Psychology Today, asking a fundamental question on whether you should be in a long-term relationship with someone highly psychopathic.

She shared results of a study in 2025 that found being in a relationship 'with a partner high in psychopathy' is generally not good for you, but she pointed to some potential 'spillover' that could positively impact someone's work life.

The study, by Aaron Hissey and colleagues of Victoria University of Wellington, involved 490 long-term couples in New Zealand filling out forms on relationship and work satisfaction.

What do you see? (Getty Stock Images)

Psychopathy measures were assessed through 'fearless dominance', impulsivity and cold-heartedness, and how these, over time, impact the partner.

Addressing 'spillover' into working life, Whitbourne said of the study's results: "There was also evidence for psychopathy’s impact on partner success, but not in a way that the authors expected.

"People in relationships with coldhearted partners actually had higher occupational prestige rather than lower, which is what negative spillover would predict."

The professor interpreted this as someone 'unabashedly going for what you want to get ahead' in work.

Whitbourne concluded: "To sum up, there should be caution tape around a partner high in psychopathy when you’re considering getting into a long-term relationship.

"However, there may be some unintended benefits of taking a page or two from their playbook."