4 ways to catch a liar

From tense facial muscles to halting speech patterns, body language expert Carolyn Finch highlights four physical signs to look for if you think someone is lying

Most people lie, whether they're covering up something sinister or just embarrassed over a mistake. Research conducted a few years ago at the University of Massachusetts found that 60 percent of participants lied at least once during an observed 10-minute conversation.

If you're trying to get to the bottom of a work incident, or just asking the kids who broke the TV, it's useful to know how to spot a lie (Learn interview and interrogation techniques in How to Spot a Liar).

Body language expert and human behavior specialist Carolyn Finch, who served as a consultant and analyst for media outlets during the OJ Simpson trial, has appeared on CNBC News and the Ellen Degeneres Show. Here Finch gives a rundown of the hallmark physical signs people display when they are trying to put one over on you (Watch the video for Carolyn's analysis and her recall of famous cases of alleged lying).

How to Spot a Liar

Body language expert Carolyn Finch details some physical signs to look for when trying to spot a liar.

Obviously these signs don't guarantee that lying is in progress, but they're valuable clues to recognize.

Tense facial expression

When people lie, said Finch, they tend to smile with only the lower muscles in their face. A liar might try and fake a smile to look genuine or at ease. But a real smile uses the entire face, including the eyes.

"You will see smiling that is artificial," said Finch. "It's down here (the lower face) instead of in the eyes."

Hesitant speech and pausing

A liar will speak hesitantly, according to Finch, and often pauses frequently when answering a question. A liar might also repeat words or stutter, she said.

"A person who is pausing is thinking," said Finch. "The eyes go up and around and down to think about what they are going to say next."

A liar might also place a finger in front of their mouth, as if contemplating, when they are about to say something that is untrue.

"When they open the mouth, they may give you whole different story than what they might have said when they were thinking with the finger over their mouth."

Nervous behavior and overemphasis

Other face touches might include nose rubbing or touching underneath the nose, all indicators the person is uncomfortable. And watch hands closely, which are an easy way to spot nervousness.

"Sometimes there is tremor, definitely in the hands," said Finch, who also noted the jaw might shake, too.

"The jaw is usually level with floor when a person is talking to another person. But (when lying) the jaw is going to go down, there can be a tremor, it's tight, like: 'Yes you better believe me,' and they're overemphasizing it."

Join the CSO newsletter!

Error: Please check your email address.

Tags social engineering

More about BillCNBCNBC

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Joan Goodchild

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts