Here are a few indicators that someone is lying.
There is not ONE expression alone that means someone is lying. They have to occur in clusters.
Slip of the tongue -Emotion specific
Tirades - Emotion specific
Indirect speech - Verbal line not prepared, negative emotions, most likely fear
Pauses and speech errors - Same as above
Raised voice pitch - Anger and/or fear
Voice pitch lowered - Sadness
Louder, faster speech - Anger, fear, and/or excitement
Slower, softer speech - Sadness and/or boredom
Emblems - Emotion specific
Illustrators decrease - Boredom, line not prepared, weighing each word
Manipulators increase - Negative emotion
Fast or shallow breathing - Emotion
Sweating - Emotion
Frequent swallowing - Emotion
Micro expressions - Any specific emotions
Squelched expressions - May only show that some emotion was interrupted but not which one
Reliable facial muscles - Fear, sadness, or happiness
Increased blinking - Emotion
Pupil Dilation (getting bigger) - Sexual arousal, emotion
Tears - Sadness, distress, uncontrolled laughter, happiness
Facial reddening - Embarrassment, shame, anger, maybe guilt
Facial blanching - fear or anger
The 7 basic microexpressions: Happiness, sadness, fear, anger, surprise, contempt and disgust. There are others such as shame, pain, sorrow, and guilt.
Happiness - reliable facial muscles around eyes, corners of mouth slightly turned up
Sadness - upper eyelids and outer edges of eyebrows will droop. Lip corners will be slightly pulled down
Anger - lips narrowed and pressed together tightly. Glaring eyes and eyebrows slanted downwards
Disgust - upper lip raised generally exposing teeth, along with wrinkling of the nose and wrinkles in forehead
Fear - lips stretched horizontally towards ears, lower eyelids tensed and upper lids raised. Brows raised and pushed together
Surprise - widened eyes and raised brows. Mouth will be open slightly
Shame - look down to either side. Also guilt.
Pain - squinting eyes, exposed teeth, raised lower eyelids
Sorrow - raised voice
Emblematic slips, also called a Freudian slip, are expressions that show people's emotions, and they just kinda "slip" out. An example would be the middle finger in an interview. The liar may try to conceal it, and somehow the lie catcher will be able to see it. This expression expresses anger.
Shrugging of one or both shoulders - Lie
Defying head movements - Lie i.e. saying "yes" but nodding "no"
Pupil constriction then dilation (pupils get smaller then return to normal) - Truth
Hand/finger movements - Lie i.e. rubbing/fidgeting with the hands while telling a story
Fist clench/twitching, middle finger - Anger
Tapping finger - Impatience
Controlled smile - both sides of face rise up and fall
Hiding something (This rule ONLY applies to men) - Itchy nose - Men have reptile cartilage under their noses.
Hands covering private parts - Feeling vulnerable. i.e. Churchill at Yalta (See image below)
Clasping and locking hands behind the head when sitting -Indicates that they think they are smarter than the other person
Churchill is on the left. Look at his hat.
Misc. All the stuff you HAVEN'T learned yet...
Raised voice pitch (i.e. phone calls) - Smile
Recalling specific details many years later - Lie
Unilateral eyebrow raise - Lie
Small inhale - Lie
Eyes to right - Truth (SOMETIMES)
Eye-shift downward - Lie
Contempt frown - Lie
Controlled smile - Lie
Delayed answer - Lie
Lip-lick - They want to kiss you
Evasion technique/Stonewalling - Hiding something. i.e. "So what's behind the door?" "Did I show you my new tattoo?" Evading the question so you don't have to answer it.
Hard swallow - Lie
Crossing the arms - Defensive posture
If someone with a higher authority (such as police officers, teachers, principals, etc.) are interrogating the subject, and they ask where something is, wherever they first look is where it is. i.e. If cops show up to a crime scene and ask the suspect where the gun is, and the suspect looks at their car first, it's somewhere in the car.
*Some expressions are false when the subject is either intoxicated, or has used drugs recently. Example: Happiness: No tears of happiness, fake smile, etc...
*When people tell the truth, they do not feel the need to recall small details many years later. Example: "Oh I think it was cloudy the day it happened." Recalling the weather condition would be a hint of a lie. Who cares what the weather was whenever something happened??
*Listen for distancing language: Example: "Mom" and "Mother"
*Duping delight: Some people can't help but have a controlled or "squelched" smile when they know they've deceived someone.