New psychology research shows people consistently overestimate how much others lie and cheat

People consistently assume that others are much more likely to lie and cheat than they actually are, and correcting this pessimistic outlook can improve social trust. A recent paper published in the Journal of Experimental Social Psychology suggests that individuals overestimate the dishonesty of their peers by a wide margin. Providing accurate information about actual honesty levels tends to reduce support for heavy workplace surveillance and fosters a more positive view of human nature.

Honesty functions as the invisible glue that holds social and economic systems together. When people act dishonestly, society pays a steep price in the form of unpaid taxes, insurance fraud, and retail theft. Psychology and economics have extensively documented the factors that tempt people to lie for personal gain. However, the beliefs people hold about the inner morality of others have received less attention.

Beliefs about how others behave shape human interactions just as much as reality does. If someone assumes their coworkers or neighbors are prone to cheating, they might support highly restrictive policies or struggle to collaborate. In existing literature, some findings are consistent with the prediction that people would overestimate the dishonesty of other people. Studies on cynical thinking suggest people might assume the worst about others to protect themselves from exploitation.

Other research on lie detection points to a truth bias, meaning people tend to assume others are telling the truth by default. This perspective predicts that people might underestimate how often others lie. To resolve these competing ideas, the researchers designed a large project to map the gap between expectations and reality. They wanted to see if human beliefs about dishonesty match the actual rates of deceptive behavior when personal outcomes are not at risk.

“I wrote my PhD dissertation on moral decisions,” said study author Jareef Martuza, an assistant professor of strategy and management at the Norwegian School of Economics. “In my experiments, I’d give hundreds of participants a chance to lie and receive a monetary bonus. Out of curiosity, I also asked them to make predictions about what percentage of others would cheat.”

Martuza explained his initial expectations. “I thought people on average would be able to correctly estimate,” he said. “But they seemed to consistently overestimate. Ironically, my beliefs about others’ beliefs were wrong. So, we started to formally study using more experiments as a systematic overestimation of others’ dishonesty would be important to know and communicate to others.”

The scientists began with a comprehensive internal analysis of their own unpublished data. This included 31 different comparisons across 11 experiments, involving 8,126 responses from 7,340 unique participants. In these experiments, participants faced situations where they could anonymously lie to receive a small financial bonus without any risk of punishment.

Most of these tests used a simple die-rolling game. Participants mentally guessed a number, observed a die roll, and then reported if their guess was correct. Because the true probability of guessing right is mathematically known, the researchers could calculate the actual percentage of people who lied to get the money at the group level.

In a different task, participants played a color-matching game. They could falsely report seeing a memorized color on a new list to win cash at the expense of an anonymous partner. In all these experiments, the participants making the choices were also asked to estimate the percentage of their peers who would behave dishonestly.

The data revealed a massive overestimation of dishonesty. Across the 31 comparisons, participants overestimated the rate of dishonest behavior by an average of 13.6 percentage points. The researchers noted that 63.5 percent of the participants overestimated cheating by five percentage points or more. Only about a quarter of the participants underestimated the rate of cheating.

“People on average overestimated what percentage others behave dishonestly by about 14 percentage points, which is a substantial effect,” Martuza noted. He and his team did not anticipate how robust this pattern would be. “We were quite surprised at how consistent the effect was across several contexts, and individual differences such as whether the person had behaved honestly or dishonestly before reporting their beliefs,” he said.

This pessimistic bias was particularly strong in economic games involving real money, compared to hypothetical retail scenarios. The scientists suggest that real monetary incentives make the temptation to lie more salient. Participants might project this heightened temptation onto others, inflating their perception of widespread cheating.

The scientists also conducted supplemental surveys asking people what they thought others’ beliefs would be. “In our supplemental studies, most people were aware that others hold inaccurate beliefs about honesty, but they disagreed on whether people overestimate or underestimate dishonesty,” Martuza explained. “This suggests our finding was not so predictable.”

Next, the researchers tested whether correcting this pessimistic bias could change how people view the world. In a second study involving 981 adults, the scientists split participants into two groups. The treatment group read a short text detailing actual research findings. This text explained that 70 percent of people are honest in these behavioral tests.

The text also explained that people tend to mistakenly overestimate cheating by 14 percentage points. The control group received a general description of the research but no specific statistics. After reading the text, all participants answered questions measuring their broader social expectations.

Those who received the factual information about high honesty levels reported significantly more positive views of other people. They showed higher levels of general trust and a stronger belief that others try to be fair and helpful. The informed group also displayed lower levels of general cynicism, providing evidence that correcting one specific negative belief can improve social outlooks broadly.

The authors then focused on professional managers, who often design rules and monitoring systems for workplaces. In a third study, 285 professional managers answered questions about the die-rolling game and real-world scenarios. The sample included directors, vice presidents, and executives recruited through an online survey platform.

The managers estimated the prevalence of six dishonest behaviors. These included workplace theft, padding expense reports, overreporting hours, buying counterfeit goods, insurance fraud, and shoplifting. For each action, the managers provided estimates for how many people actually commit these acts versus how many would admit to them.

Like the general population, the managers drastically overestimated how many people would cheat in the die-rolling game. They predicted that 55 percent of people would lie, which was 25 percentage points higher than the true cheating rate. The managers also estimated that the actual rates of real-world cheating were much higher than what people would confess to in anonymous surveys.

This moral pessimism predicted a stronger preference for strict countermeasures, like increased surveillance and monitoring, to prevent theft and fraud. To see if information could change these policy preferences, the scientists conducted a fourth study with 741 managers. Similar to the second study, half of the managers received the factual data showing that most people are honest.

The other half served as a control group. Both groups then rated their support for surveillance and strict rules in the workplace. They used sliding scales ranging from negative 50, indicating a desire to decrease countermeasures, to positive 50, indicating a desire to increase them greatly.

The researchers wanted to establish a causal link between knowing the facts and choosing workplace policies. The information treatment worked as intended. Managers who learned the true rates of honesty expressed significantly lower support for freedom-restricting countermeasures. Providing evidence-based statistics helped calibrate their risk assessments, and it reduced the perceived need for intense monitoring systems across five out of the six hypothetical business scenarios.

“In our paper, we present preliminary evidence that the more people overestimate, the more people endorse surveillance measures, and correcting misperceptions seems to reduce surveillance preference,” Martuza said. However, he pointed out a boundary to these findings. “But while we showed that correcting misperceptions changed people’s stated attitudes toward surveillance policies, we have not yet tested whether it changes actual organizational decisions.”

While the project provides strong evidence of a pessimistic bias, readers should note a few caveats. “We are not saying that people are perfectly honest,” Martuza clarified. “About 30% of participants in our studies did cheat when given the chance. Our main finding is that people think the number is much higher than it actually is.”

The geographic focus of the sample also leaves some questions open. “Our participants were all based in the U.S. and recruited online, so we do not yet know whether the same pattern holds across different cultures,” Martuza added.

The exact psychological mechanisms behind this bias also remain an open question. It is possible that negative events simply stick in the human mind more easily, coloring general perceptions. Another possibility is a halo effect in the second study, where hearing positive news automatically triggers a globally positive mood. A halo effect occurs when one positive trait or piece of information influences how a person perceives everything else about a subject.

Additionally, reading a short text in an online survey does not replicate the complex decision-making processes of a real corporate environment. Online survey platforms rely on self-reported job titles, which might not always perfectly represent top-level decision-makers. The authors note that organizational culture and financial costs also dictate policy. Overestimating dishonesty is likely just one of many factors that influence a manager’s support for strict surveillance.

“Personally, this project has been a revelation on how often our beliefs do not match reality,” Martuza reflected. “My colleagues and I are exploring other aspects of moral beliefs, and misperceptions in other areas where wrong beliefs can be consequential.”

Recognizing this bias could help individuals navigate daily interactions with a bit more grace. “We tend to overestimate how dishonest others are,” Martuza concluded. “Of course, the potential downside to trusting strangers can be significant. But most people do not seem to cheat even when their decisions are anonymous, there is no punishment, and there are no reputational consequences. So, we might want to reflect a bit on whether our pessimism about other people’s morality might be justified.”

The study, “Beliefs versus reality: People overestimate the actual dishonesty of others,” was authored by Jareef Martuza, Helge Thorbjørnsen, and Hallgeir Sjåstad.