Being able to determine who’s lying and who isn’t is one of the most important communication skills you can have. The seemingly honest person who’s spinning a web of lies can trap you just as easily as the person who strikes you as sketchy. The longer you know someone, the better you can be at spotting their deception, but many situations in life involve gauging the words and/or actions of a stranger.

Take the common experience in which you’re shopping for a new outfit. It’s in the salesperson’s best interest to make the sale, and in some cases, a more expensive purchase benefits them more than a deeply discounted one. You, however, need an honest opinion. Lacking this person’s backstory, you need to figure out some other way to get direction than just relying on their words.

There are lower stakes in this situation than in others where judgments of honesty could have more significant consequences. Think about politicians who promise glorious results if you vote for them but who, once elected, turn their back on their constituents. What did you, and maybe thousands or millions of others, miss in what now seem like obvious clues?

The Honesty-Humility Trait in Personality Theory

One of the two most prominent contemporary personality theories is the HEXACO model, in which the “H” stands for “honesty-humility.” Proponents of this theory argue that the truly honest have an inherent inability to lie. Whether salesperson or politician, such an individual would be virtually incapable of steering people in the wrong direction.

However, might something else be involved in the conceptualization of honesty? According to Willamette University’s Caleb Reynolds and colleagues (2025), honesty has many angles to it. Being high in the trait of honesty could mean that you tell the truth, but it could also mean that you’re direct, straightforward, don’t steal or cheat, and keep your promises. Though ranked as “the most important trait” of all when people judge others, “it’s unclear what aspects of honesty are central to people’s conceptualizations of the trait” (p. 574). Thus, when you set out to detect a liar, you will be on the lookout for honesty, but is this enough? And would someone high on the H trait in HEXACO be unlikely to lie, or might that person just show these other behaviors that go along with being morally upstanding?

Getting to the Roots of Honesty

Across a series of five studies, the Willamette U. research team used what’s called a “prototype analysis” to find out what people really mean when they refer to someone as honest. By extension, this analysis could help serve the purpose of allowing you to cut to the chase when you decide whether someone’s lying or not. You could ignore a bunch of irrelevant behaviors (like the person doesn’t usually steal) and instead focus on what will really matter.

In a prototype analysis, researchers ask people to provide a list of qualities that they think define a concept, and then analyze the responses to detect commonalities. Raters also provide their evaluations of how central a quality is to the concept as well as whether they use that concept when judging other people.

Each of the five studies in the Reynolds et al. publication involved online adult samples ranging from 200 to 400 with participants averaging 40 years or so in age. In the first study, participants responded to the prompt to list 15 qualities associated with the term “honest.” Right off the bat, truthfulness and trustworthiness emerged as the top two, with Sincere running in third place. However, some of the other top-rated qualities, the authors noted, seemed “strange,” such as content, selfless, intelligent, and sociable.

To figure out what was going on, they asked their second sample to indicate whether these traits were part of honesty or just associated with honest people. Using a drag and drop menu, participants indicated which qualities are “definitive” of honesty and which are “associated with” honesty. Now, with this refinement, Truthfulness emerged once again at the top (94% placed it there), but other traits still tagged along with it (e.g., sincere, open, straightforward).

The next test asked participants to respond as quickly as possible to lists of traits with the judgment of reflecting HONESTY (yes or no). Truthfulness again came out the winner, but so did terms like accurate, accountable, and moral.

Moving on in the fourth and fifth experiments, participants were called upon to judge behaviors that would quality as honest or not. Again, this phase began with asking participants to provide a listing of honest behaviors which was then followed by the final phase in which the highest-scoring behaviors were rated as honest or dishonest. After consolidating these ratings, “Telling the truth” had the highest ratings for honesty and “Lying” for dishonesty. Other qualities that hung together with these included adhering to norms, respecting other people’s possessions, and being straightforward and open.

Where traits and behaviors deviated, Reynolds and his coauthors maintain that trait-level analyses emphasize communicating honestly (being open), and behaviors emphasize possession-related acts (not stealing). These, however, are secondary to truthfulness. As the authors concluded, the HEXACO measure’s scale “does not feature the core of lay honesty conceptualizations: truthfulness” (p. 591). Truthfulness, they go on to conclude, “seems to be both the most central and the ‘purest’ facet of honesty” (pp. 591-592).

Do These Conceptualizations of Honesty Help in Finding Out Who’s Lying?

All of this may be of some esoteric interest to you, especially if you’re a fan of personality trait theories (and now know where one falls short). But will the results of this study help you figure out who is, after all is said and done, telling the truth?

It’s a well-known fact in the deception literature that behavioral cues are unreliable when judging whether someone is telling the truth or not. A good liar has a myriad of ways to mislead and distract you. However, what this study does provide you with is a set of behaviors and traits not to confuse with honesty. Someone may be open, direct, and seem smart, but it doesn’t necessarily mean the person is honest.

Looking for that pure quality of truthfulness means that you hone in on the most central feature of someone’s personality and behavior as quickly as you can and not get distracted by what “seems” honest. Often, this doesn’t take any more effort than thinking hard about what’s going on a situation. You know if something looks good on you or not. So what if the salesperson smiles, seems nice, and shows empathy (other honesty-adjacent traits found in the Reynolds et al. study)? Similarly, when judging a public figure, your own sensibilities can inform you as to whether they’ve got their fingers crossed behind their back every time they make a statement or campaign promise. You don’t need their entire record, all you need is some common sense.

To sum up, cutting through to the essence of honesty can help you separate what’s relevant from what’s not in making decisions about whether to trust other people. By the same token, knowing that you are judged on these very same criteria can also point you toward a more honest and fulfilling pathway for yourself.