How to Tell if Someone is Lying

Guide Note

Being able to detect a liar is a skill that many people would like to have. It is useful for law enforcement and security agencies as well as business owners and managers. Many different methods have been developed in the pursuit of the truth. You should find one or two of them useful if you want to know how to tell if someone is lying.

Table of Contents

Lie Detection Tips

  1. There is no universal set of behaviors that indicate someone is lying.
  2. Liars will fidget to release nervous energy.
  3. Microexpressions are brief flashes of emotion that will indicate someone's true feelings.
  4. Polygraph machines are about 70 to 80 percent effective.
  5. Voice stress analysis is only 50 to 60 percent effective.

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Introduction

  • As much as we might lie, few will admit that they want to be lied to. How can you tell if someone's lying? There's no 100% way to know for sure, but the following methods may help you start to distinguish the fibbers from the saints.

Method 1: Body Language

Movement

  1. Covering one's mouth or face.2 This often occurs when the liar feels bad or guilty for telling the lie.4
  2. Touching the nose. When we lie, the tissues in our nose engorge with blood and cause them to tingle or itch.5
  3. Nervous hand movements. This includes wringing the hands together and rubbing, picking or playing with the fingers.6
  4. Defensive behaviors such as leaning backward and crossing the arms or legs. These act as a "barrier" for the person and reduces their anxiety levels.2
  5. Holding an object in front of the body as a sort of invisible barrier.7
  6. Rubbing the neck.5
  7. Rubbing the eyes. This indicates that the person doesn't believe or disagrees with a statement.5
  8. Shuffling the feet.8
  9. Clenched jaw.8
  10. Licking the lips.8

Lack of Movement

Eye Contact

Facial Expressions

  • Facial expressions are another way of finding out if someone is lying. This can show up in several different ways:
  1. Delayed expressions or ones that last longer than they naturally would.10
  2. A prolonged smile or amazed look. Most natural expressions will fade after about four seconds.3
  3. Crooked or asymmetrical facial expressions.3
  4. Fake smile. A fake smile will involve only the lips and mouth.7

Incongruent Behavior

  • Incongruent behaviors are when there is a mismatch between actions, words, tone of voice or expression. They are often a sign of deception. They might occur in one of the following ways:
  1. Expressions do not match the person's statements.10
  2. Words do not match the body language. A person might nod their head while saying, "No."5
  3. Mismatch between a person's expression and their tone of voice.6
  4. Body gestures and facial expressions are out of sync. One often occurs after the other.3
  5. Misuse of a common gesture. Also called "leakage emblems," this type of misplaced gesture might include making the "okay" sign below the waist or shrugging one shoulder instead of two.2

Method 2: Microexpressions

  1. It is almost impossible to control microexpressions.2
  2. FACS has an accuracy rate of 76 percent.12
  3. If combined with voice and speech measures, FACS has an accuracy rate of up to 90 percent.11
  4. Since it primarily depends on human analysts, it is impossible to standardize it.12
  5. A machine called "Silent Talker" has been created that is said to be able to detect microexpressions.13

Method 3: Voice Changes

  • A person's voice may subconsciously change when they are lying. This can be heard in two different ways:
  1. Upward inflections. People naturally inflect the ends of questions upwards. Some people, however, may do this when making false statements.5
  2. Rise in pitch.14 A person's voice will rise in pitch when they are angry, afraid, upset or lying about 70 percent of the time.3

Method 4: Statement Analysis

  1. Use less first-person pronouns. A liar will try to distance him or herself from the lie by reducing their use of "I" and "me."11 Instead they will often use third person pronouns such as "you," "we," "it," "they," "them" or even drop the pronoun altogether.9 15
  2. Use the pronoun "that" as a distancing word'. One of the best examples of this is Bill Clinton's infamous statement, "I did not have sexual relations with that woman, Miss Lewinsky."16
  3. Shift pronouns. A liar often shifts their pronoun use. For example, they might go from "we" to "they," say "my wife and I" instead of "we" or switch from saying "my car" to "the car."17 15
  4. Use more negative emotion words. Liars will use words such as hate, worthless and sad as if subconsciously expressing their guilt or anxiety.11
  5. Use fewer exclusionary words. Liars have problems distinguishing between what they did and did not do and, as a result, will avoid using words such as except, but and nor.11
  6. Use convincing statements such as "to tell you the truth" or "to be perfectly honest."9
  7. Use noncommittal phrases such as "I think," "I believe," "to the best of my knowledge" or "kind of."15 An analysis of Jeffery MacDonald's statement about what he claimed happened on the night his wife and two daughter were killed showed he used 29 such phrases.18 MacDonald was found later found guilty of the murders.
  8. Use less cognitive words such as "understand" and "realize."14
  9. Change or use the incorrect verb tenses.15 Liars will often shift verb tense when telling a lie or use the incorrect verb tense. Scott Peterson made this mistake in a January 28 interview on Good Morning, America when he said, "I mean we took care of each other, very well. She was amazing." He promptly corrected himself and added, "She is amazing."19
  10. Add extraneous information. Liars feel the need to convince you of their story and will often add extra information to their stories.15
  11. Change nouns to refer to the same thing.15 People have specific vocabularies. Any deviation from this vocabulary is a good indicator that their reality has shifted from the truth to a lie.15
  12. Mix up small details. Honest people have a clear picture of what happened and will be consistent with the smaller details. Without this mental image, liars will have trouble with minor things and will not be as consistent about them.4
  13. More likely to make passive statements. For example, they will say "I'm not guilty of the crime."16
  14. Often request you to repeat your questions.9 This gives them more time to consider their response.

Method 5: Polygraph Machine

  1. Research indicates that polygraph machines have an accuracy rate of 80 to 90 percent.20
  2. Because popular opinion puts polygraph success rate at almost 100 percent, it works well as a deterrent to lying and often elicits confessions.20
  3. False positives, or when a person tests positive for lying even though they are telling the truth are more common than false negatives.6 This is because often an innocent person is afraid that their answers might be perceived as untruthful, and the machine is registering that fear.14
  4. Although polygraphs can indicate when someone gets anxious, it cannot determine what is causing the anxiety.21
  5. A 1998 Supreme Court ruling stated that blocking polygraph tests is constitutional because "there is simply no consensus that polygraph evidence is reliable."21

Method 6: Voice Stress Analysis

  1. Voice stress analysis is more cost effective and less obtrusive than a polygraph machine.23 24
  2. Analysis does not have to be in person. It can be done over the phone or with a recording.25
  3. Voice stress analysis has been used by the British insurance industry since 2002.20
  4. Scientific research, including studies done by the U.S. Department of Defense, place its success rate at about 50 percent.23 20
  5. Voice stress analysis machines can be used by the government for employment screening and by private security cases, but subjects must be aware that they are being used.25
  6. Voice stress analysis cannot be used in U.S. courts as evidence, but several states allow it to be used during criminal investigations.25

Method 7: Truth Serums

Conclusion

  • As you go on your own quest to find the truth amidst the lies, remember some advice that FACS creator and psychologist Paul Ekman uses when trying to detect the truth, "You must use lying as a last interpretation and rule out everything else that's possible."11 If you go looking for lies, you are more likely to find them, even if they don't exist. If you keep a neutral point-of-view, you're more likely to uncover the truth—even if it's lies you're looking for.

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References for How to Tell if Someone Is Lying

  1. Psychology Today: Spotting the Liar (January/February 2006)
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 Law Library: The Detection of Deception Via Non-Verbal Deception Cues
  3. 3.0 3.1 3.2 3.3 3.4 TIME: The Fine Art of Catching Liars (April 22, 1985)  WARNING: Pop-Ups
  4. 4.0 4.1 About.com: Liar, Liar How Can You Tell?  WARNING: Pop-ups
  5. 5.0 5.1 5.2 5.3 5.4 Entrepreneur.com: Are They Lying to You?  WARNING: Ad-heavy
  6. 6.0 6.1 6.2 6.3 6.4 BBC: Detecting Lies
  7. 7.0 7.1 Marc and Angel Hack Life: 25 Acts of Body Language to Avoid (July 7, 2008)
  8. 8.0 8.1 8.2 MSNBC.com: Roger Clemens licks his lips. But does that mean he’s lying? (February 13, 2008)
  9. 9.0 9.1 9.2 9.3 MSNBC.com: Why People Lie — and How to Tell if They Are (January 31, 2004)
  10. 10.0 10.1 About.com: Believe What You See
  11. 11.0 11.1 11.2 11.3 11.4 11.5 APA Online: Detecting deception (July/August 2004)
  12. 12.0 12.1 12.2 TIME: How to Spot a Liar (August 20, 2006)  WARNING: Pop-Ups
  13. 13.0 13.1 MSN Encarta: How Can You Tell If Someone Is Lying? Part III
  14. 14.0 14.1 14.2 14.3 Psychology Today: Spotting the Liar (January/February 2006)
  15. 15.0 15.1 15.2 15.3 15.4 15.5 15.6 FBI.gov: Statement Analysis: What Do Suspects' Words Really Reveal?
  16. 16.0 16.1 ESPN: Body Language Analyst Breaks Down Clemens, McNamee Performances  WARNING: Pop-ups
  17. National Association of Investigative Specialists Statement Analysis: New Investigative Processes to Help You Uncover The Truth
  18. Statement Analysis: Jeffrey MacDonald
  19. Statement Analysis: Scott Peterson Case
  20. 20.0 20.1 20.2 20.3 20.4 Guardian Unlimited: Testing Times (September 18, 2007)
  21. 21.0 21.1 NPR: Foolproof Test for Catching Liars Still Elusive
  22. Federation of American Scientists: Voice Stress Analysis Evaluation Begins (September 23, 1997)
  23. 23.0 23.1 Government Technology: Good Science or Just Bunk? (June 7, 2006)
  24. International Society of Voice Stress Analysts: The Truth about Voice Stress Analysis / Polygraph Controversy
  25. 25.0 25.1 25.2 The New York Times: It's the Way You Say It, Truth Be Told
  26. The Washington Post: Some Believe 'Truth Serums' Will Come Back (November 20, 2006)

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