How to spot toxic people and take back control

Below, Leanne ten Brinke shares five key insights from her new book, Poisonous People: How to Resist Them and Improve Your Life.

Leanne is Associate Professor of Psychology at the University of British Columbia, where she directs the Truth and Trust Lab. She has been studying deception, distrust, and dark personalities for the past 20 years.

What’s the big idea?

Most people are far kinder—and more trustworthy—than we assume. The real danger comes from a small group of manipulative personalities who exploit our good nature. Once you understand how they operate, you can spot them early and take back control.

Listen to the audio version of this Book Bite—read by Leanne herself—in the Next Big Idea App, or buy the book.

1. Most people are better than you think

Imagine that I gave you $10 and asked you to make a decision: keep that tenner and go on with your day, or hand it over to a stranger you’ll never see again. If you take the latter option, that $10 will automatically quadruple. That stranger now has $40 and a decision of their own to make. They can keep it all for themselves or split it with you. Do you trust a stranger to double your money?

When researchers asked participants in a study this same question, only 45 percent said that they expected people to split the money. Researchers played out the scenario and found that nearly 80 percent of people actually shared their earnings. That’s right, the vast majority of people weren’t selfish or mean. They were kind and considerate enough to do the fair thing.

Another field study had research assistants drop off more than 17,000 “lost wallets” at hotel front desks and train station lost-and-founds around the world. Some of these wallets had no money in them. Others had about $15, and still others had nearly $100. Researchers waited to see how many people would try to return the wallets to their rightful owners. You might expect that the fattest wallets would be least likely to find their way home, but the opposite was true. The more money people found, the more likely they were to return it. People went out of their way not to feel like they were stealing.

These and many other similar findings reveal that most people aren’t often selfish or mean. They aren’t consistently violent or abusive either. They’re kind, honest, and concerned about others.

2. A few people do most of the damage

Most people aren’t the problem. A few people are. People with psychopathy have callous, manipulative, impulsive, and antisocial personality traits. They don’t experience emotions as others do. You know that guilt you feel when you drop the ball at work? Or when you say something cruel in a moment of stress or anger? They don’t experience those pangs. People with psychopathy can commit horrific acts of violence without any remorse for the people they hurt or kill.

“They make up just one percent of the general population, but account for about 20 percent of incarcerated people.”

They also have inflated egos and might come across as having a holier-than-thou vibe, even though they’re anything but. People with psychopathy manipulate others using superficial charm and lies to get what they want. They live for momentary pleasures, seeking sex, money, and dominance. Long-term planning isn’t in their playbook—they act on impulse and care little about following the rules. It is no wonder then that people with extreme, clinical levels of these traits tend to find themselves at odds with the law. They make up just one percent of the general population, but account for about 20 percent of incarcerated people.

The more psychopathic traits that people possess, the less likely they are to share the spoils of that economic game I mentioned earlier. The less trustworthy they are, in general: people higher in psychopathic traits tell more lies, cheat more often on their romantic partners, and spend more time trolling in online forums. They rain more abuse on their subordinates at work and their families at home, and they’re more likely to favor an authoritarian approach in politics. Being on the receiving end of these behaviors costs us.

Let’s turn it into dollars. Researchers estimated the total cost of crime in the U.S., including money spent on prisons and legal fees, as well as the cost of security systems, medical care for victims, and the time we spend avoiding or recovering from crimes. That number topped $5 trillion annually. If people with psychopathy make up 20 percent of all incarcerated individuals, you might pin 20 percent of the cost on them. But it turns out that people with psychopathy commit 50 percent of all serious crimes. The total annual cost to society: $2.5 trillion U.S. dollars.

Most of us experience the costs of dark personalities not in dollars and cents, but in stress, fear, and cynicism. Maybe a supervisor at work, an ex-partner, a friend, or even a family member sprang to mind as I described the constellation of personality traits that make up psychopathy. While these people in your life may not meet clinical cut-offs for a disorder, higher-than-average levels of these traits can bring out-sized pain to those in their orbit. Research shows that up to about 20 percent of the population score higher on dark traits. These are the people who tend to backstab us at work, troll us online, treat us abusively in our romantic relationships, and more.

3. Dark personalities thrive on our (false) assumptions

Research suggests that people rarely tell lies. When you ask people, “How many times have you lied today?” the most common answer is zero. So, it makes a certain kind of sense that people also tend to assume that others are telling the truth most of the time. People have such a strong truth bias that it rarely even occurs to them that someone might be lying. But dark personalities? They lie a lot, and because of our truth bias, they get away with it a lot, too.

We often use our own experience as a starting point for understanding how others might feel, think, or act in a given situation. That works well for people similar to us, but it really backfires with dark personalities. When someone with psychopathic traits does something wrong, our first impulse might be to guilt or shame them. While that might have worked to curb your bad behavior, they don’t experience guilt or shame. Alternatively, you might try to punish them, but again, that will likely prove ineffective. The brains of people with psychopathy don’t react to punishment like others do, and so it doesn’t shape future behavior like it does for most people.

“That works well for people similar to us, but it really backfires with dark personalities.”

Other false assumptions seem to benefit dark personalities, too. We tend to mistake confidence for competence, giving people with narcissistic personality traits a leg up when it comes to choosing leaders. Similarly, we might assume that people in positions of power need to have a bit of callousness, fearlessness, or the ability to manipulate to get the job done. But research tells a different story. There is strong evidence that narcissistic leaders tank team performance, and psychopathic traits don’t help investors maximize profits. In fact, they make less money than their less psychopathic peers.

4. Understanding poisonous people provides an antidote

Researchers have amassed a ton of data about dark personalities, and you can use that information to detect dark personalities early, make clear-eyed decisions about whether you want to stay or go in a relationship with one, and actively contain the damage if you decide to stick around. Some of the strategies are surprisingly simple.

In a 1961 CIA report, then-President JFK was presented with insights into the personality of Soviet leader Nikita Khrushchev. Khrushchev had some dark traits. The report describes him as impetuous, ruthless, and prone to taking risks. He was at least somewhat narcissistic and was a wily manipulator. Khrushchev was also described as having the capacity to charm and smooth-talk others to his advantage. He did well in unscripted, face-to-face interactions. The CIA’s analysis notes that he was something of a chameleon, capable of playing different roles depending on the situation: “His personality has more impact than his words.”

It’s not just Khrushchev that seemed to have an in-person advantage. Research on parole board decisions finds that inmates with clinical levels of psychopathy are more likely to be released than their less psychopathic peers, despite a higher likelihood of reoffending. In a more benign scenario, dark personalities were able to negotiate a sweeter deal for themselves when selling a pair of concert tickets in person than when the same negotiation occurred over text. Shifting to text can help neutralize poisonous people, providing a simple, research-backed strategy for managing interactions with everyday dark personalities.

“Shifting to text can help neutralize poisonous people.”

There are other critical things we’ve learned, too. You know how punishment doesn’t work so well? That’s due to a failure of attention. Drawing someone’s attention to the punishment when it’s doled out can help make it more effective. And you know what might work even better than that? Rewards. So, when a generally callous and manipulative person does something kind or honest for once, reward them. Give them a reason to do it again.

5. The problem is smaller than you think

If a relatively few people are causing most of the harm, that means we can make huge headway by focusing on containing just a small group of individuals—a much easier challenge than changing all of humanity. Fortunately, science has provided us with powerful tools.

You can already detect poisonous people, and you can learn how to do that better and faster. There are a series of red flags and patterns that become evident if you spend enough time around a dark personality. Even first impressions based on a few seconds of observation contain a kernel of truth.

Detection is a critical skill to gain, but it’s not the only tool you need. I often hear people say that if you see these traits, run. Run far and fast in the opposite direction, and honestly, that’s a strategy you should keep on the table. But you won’t always be able to leave a relationship with a dark personality that is poisoning your life—perhaps you won’t even want to. To stay or go is your choice, but electing to stay doesn’t mean you have resigned yourself to becoming a victim. You can learn to manage the poisonous person in your midst.

Enjoy our full library of Book Bites—read by the authors!—in the Next Big Idea app.

This article originally appeared in Next Big Idea Club magazine and is reprinted with permission.