No one likes being lied to, but let’s face it, there are people who will lie all day, every day. This person may be a problem employee, your boss, your child, your spouse or a sibling.  So, how can you tell if you are being lied to? It has been observed that lying causes detectable physiological changes in people, and if you are observant, you will be able to notice the changes.

The easiest way to detect these changes is with a polygraph, or traditional lie detectors, and to lesser extents with CVSA (computer voice stress analysis, though this method has fallen out of favor).  Physical changes detected by the polygraph are in heart rate/blood pressure, respiration, and skin conductivity.  Very basically speaking, a baseline reading is established using control questions and then subsequent answers are measured against that baseline to gauge truthfulness.

So, what if you don’t have a polygraph?

There are certain physical actions or indicators that most people will show when they are being deceptive. People who know that they are lying don’t want to get caught.  They are almost always nervous that you know that they are lying.  The paragraphs below describe some physical acts exhibited by liars that can give them away if you are able to spot them.

Liars like to have objects between you and them to create a protective, albeit psychological, space around them as a buffer.  Intuitively, people realize that their body language may give them away.  If you are talking to someone and they move away from you and put an object (counter, table, desk, etc.) between you and them, they may be trying to “block” you from seeing the change in body language. Liars may also “cover” the lie by covering or putting their hand near their mouth while speaking the untruth.  They may also cover their eyes or close them (not a blink) after lying to keep themselves from seeing the reaction of the person being lied to.

Fidgeting is another sign. If a person pulls their ear, plays with their hair, straightens their clothes, or does any number of fidgety things, all during certain patterns of questioning, it is a pretty good indication of untruthfulness.

Another good give away is called a verbal/non-verbal disconnect. Have you ever seen a person answer a question by saying “yes” while shaking their head, as if saying “no” or vice versa?  This is a verbal/non-verbal disconnect.  It tends to happen in stressful situations, where the lying individual cannot control all aspects of their body language.  Therefore, the body language and verbal language are not in sync.

Eye movement can indicate deception, but you need to establish a baseline first.  Most people tend to look in one direction when they think before honestly answering a question (for example, up and to the left), but will look in another direction (up and to the right) when lying. The only exception to this is if there is a door in the liar’s filed of vision.  They usually tend to look for the door when lying because they want to get away from you and the situation.

Liars don’t like silence. It is the epitome of discomfort for them.  To fill this space, liars will often embellish or give long and unnecessarily detailed answers to simple questions.  They may also interject commentary where none is needed, in order to avoid the silence.  A good rule of thumb when sniffing out a liar is that he who speaks first loses. If you think you are being lied to, just stop talking.  Nine times out of ten, the liar won’t be able to stand the silence and either ask you what is wrong or go back to the last topic of conversation (a very good technique when questioning a lying child or teen).

This list of physical characteristics or indicators of lying is not exhaustive.  There have been books written and weeks worth of training courses developed to assist people in sniffing out the untruthful.

Now that we have gone over some indicators that can help to spot a liar, how do we apply this knowledge?  The first thing that you will have to do is establish a baseline for their conversational behavior.  All of the acts and indicators listed above will only be accurately discerned if you first establish a relationship or rapport with the person. This should be very easy with family, friends and acquaintances but may take some work with strangers.  The trick is to be relaxed enough with making easy conversation, which, in turn will put your subject at ease.  Once you and the subject are chatting, you will be able to observe relaxed behavior and get your baseline reactions.

Trying to tell if someone is lying to you is a lot like playing poker.  Everyone has a baseline behavior and many of them will deviate from that baseline when they are being untruthful.  In poker, these deviations are called tells.  As James Bond told Vesper Lynd in Casino Royale (2006) “In poker you never play your hand…you play the man across from you.” Interviewing or talking to a liar is very similar.  Look for the tells, many of which are listed above.

Now there is a caveat associated with this information.  These indicators will not work for all liars.  Certain people can lie without outward tells, physical changes or indicators.  A few examples of these people include sociopaths/psychopaths, small children and those trained in the arts of deception.  Sociopaths are extremely narcissistic people who lack consciences.  They don’t show signs of lying because to them, they don’t feel bad for doing it, and they think that they are smarter than you and have no fear of getting caught.  Some very small children have not yet been socialized enough to know that lying is an unacceptable behavior and thus will lie with impunity (as any parent can attest). There are also some who have learned, either professionally, in prison, or other places to control their finer body movements to give away minimal tells.  These individuals would pose a unique challenge to even the most seasoned investigators.

Hopefully your day-to-day life will not be consumed with trying to sniff out pathological liars. But the reality is, we all encounter this behavior everyday.  By applying the above skills, you should be able to detect most of the people who may be trying to deceive you and, therefore, protect yourself from their deception.