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How to Tell if Someone is Lying using Psychology?

Today’s episode of The Psychology World Podcast is a cognitive psychology and forensic psychology episode on How to tell If Someone is Lying?

This episode has been sponsored by: Forensic Psychology.

How to Tell if Someone is Lying?

Whether it’s in psychology itself or wider society, being able to tell lies from the truth is a popular idea.

Thankfully, within psychology, the scientific literature surrounding deception and lie detector is massive.

However, the same is true for the unscientific ‘popular’ literature. For example, there are thousands of books written by former professionals and other people who say X and Y is how you tell someone is lying.

There are courses too on the internet and there is so much weird information out there for people to buy and sometimes pay thousands of dollars for.

The Truth:

The sad truth is there is no one indictor or sign that someone is lying.

The main reason for this is because of individual differences.

Since the stereotypical indicators of lying are laughter, avoiding eye contact, rise in temperature and more.

Nonetheless, the great reality is we are all different so not every laughs or avoids eye contact when they lie.

Everyone has their own little tell when they lie.

Some are common.

Some are not.

Some are extremely rare.

The Consensus:

Overall, psychology research has shown humans are very bad at telling if others are lying and finding deception.

In addition, the research shows this is mainly down to two biases that were found when researcher tested the public and professionals about questioning.

Note: in this context, professionals are professional questioners and people whom it is there job to find deception and learn if people are lying.

The public were found to have a truth bias because they trusted people were telling them the truth, and they didn’t seem out deception or lies in everyday human interaction.

Whereas the professionals were found to have a Lie bias. This is where they constantly seem out lies in everyday interaction and they except people to lie.

Ways to Tell if Someone is Lying:

Despite the literature making for grim reading if you want a way to know if someone is lying.

Research has shown there are several effective questioning approaches someone can talk to know if someone is lying. For example:

Ask the Right Sort of Questions:

With words being carriers of deception and deceptions requiring more of a cognitive effort, you need to ask open questions that elicit as many words as possible.

The more words someone says the higher the chance their deception will be revealed.

Make Every Question Count:

When you want to find out if someone is lying, you don’t ask them simple questions just because you can ask.

Nor do you ask question to fill the silence.

Instead, you need to ask questions that move you towards your goal. This is to find out whether or not the person is lying to you.

Listen, Don’t talk:

This is a critical point because questioners need to say as little as possible during questioning. Since this will allow them to listen, think and consider or fully understand the responses they are being given.

Be tactical:

Whilst at first, this seems like common sense, it raises the question: how do you be tactical when questioning someone?

If you know objective facts about what actually happened, question a person on each fact.

This will allow you to know if the person is generally being truthful or not. Since if you know they’re lying or bending the truth. When you ask questions you don’t know the answer to, you know how they will behave.

Note: it’s important the person you’re questioning doesn’t know that you know the objective facts, you’re asking them about.

Switch in Timings:

Personally, I really like this point because I definitely understand it, and it is useful to confuse people with.

And yes, I am that horrible sometimes!

During questioning sessions, it can be very useful to switch between the past, present and the future intentions or tenses. Since this is often very mentally demanding for liars.

Meaning overtime liars will reveal their deception because they will make errors, contradict themselves or they contradict the facts that the questioner knows.

Enquire and Converse, Not Aggressive:

This is common sense to some extent because I think we all know the classic interrogation scene when the questioners shouts and screams at the person, and they suddenly reveal everything, is false.

In realty, when you question someone, this is a complex social interaction where both parties aren’t exactly comfort.

Therefore, this social interaction will often be more pleasant as well as far, far more productive if the person asking the questions can engage with the person in an information-gathering manner.

Instead of being aggressive, formal, and accusatory.

Ask Clarification Questions:

These types of questions get the person being questions to explain previous answers in more detail.

For liars, this is difficult because they can struggle with detail as well as there can be inconsistencies in their recapping or repeating of details.

Overall Conclusion:

Despite these psychological techniques being very good, spotting liars is still a great challenge. However, real world research has known that our ability to spot liars can significantly improve when these approaches are put together and used systematically when asking people questions.

I really hope you enjoyed today’s episode of The Psychology World Podcast.

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Bogaard, G., Meijer, E. H., Vrij, A., & Merckelbach, H. (2016). Strong, but wrong: Lay people’s and police officers’ beliefs about verbal and nonverbal cues to deception. PloS one, 11(6), e0156615.

Dando, C. J., & Bull, R. (2011). Maximising opportunities to detect verbal deception: Training police officers to interview tactically. Journal of Investigative Psychology and Offender Profiling, 8(2), 189-202.

Dando, C. J., & Ormerod, T. C. (2020). Noncoercive human intelligence gathering. Journal of Experimental Psychology: General, 149(8), 1435–144

Ormerod, T. C., & Dando, C. J. (2015). Finding a needle in a haystack: Toward a psychologically informed method for aviation security screening. Journal of Experimental Psychology: General, 144(1), 76.

Sandham, A. L., Dando, C. J., Bull, R., & Ormerod, T. C. (2020). Improving Professional Observers’ Veracity Judgements by Tactical Interviewing. Journal of Police and Criminal Psychology, 1-9.

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