Human Lie Detector
by TheSpyMaster on Apr.06, 2009, under To Dare
Dan smiled at the waitress as she refilled his coffee. Across the table Johnathan watched her with irritation until she was out of earshot. “So I hear you ran into trouble last night,” Johnathan said. “Nothing I couldn’t handle,” Dan replied with is ever-present casual grin. “The real question John is how they new I’d be there,” Dan’s eyes were suddenly unreadable as he studied Johnathan’s face. John bit his lip and looked into his coffee. His gaze still on the steaming cup he joked, “Well maybe they’re using psychics again.” John glanced up to look at Dan’s face. Those eyes stayed unreadable for a moment longer then Dan broke out into quiet laugh. “That would explain the the broomsticks and wands,” Dan joked back.
As he left the diner Dan checked the tracker he had pinned onto the inside of John’s jacket. “Well at least now I know who sold us out,” he said to himself.
The most valuable skill a spy can have is the ability to discern a lie. In the field you won’t likely have the luxury of hooking everyone up to a polygraph and even if you could it might seem a little suspicious. So how do you know if someone is lying to you?
The first thing you need to do is calibrate to your subject. Let yourself become aware of the patterns of speech and body posture as you talk to the subject. Once you feel you’ve got a feel for their normal speech you’re calibrated to them. Now you’re ready for the second step.
Ask the subject your question. It is best to try and remain as casual as possible. Allow them to think you suspect nothing. Watch for any tells. A tell is a physical indication that someone is lying. Any one tell by itself is just a clue. There may be a good reason for a quirk in how someone interacts. What you’re looking for is a pattern or a preponderance of tells.
Some common tells:
- A lack of eye contact – Many liars worry that their eyes will give them away so they will avoid eye contact when telling a lie. It can also indicate guilt over the lie being told.
- A change in voice pitch or tone – Nervousness can cause the throat to constrict during a lie. This can be very subtle or hard to miss depending on the person.
- A change in speed of speech – Some people will try to rush through a lie making a noticeable change in the speed in their speech pattern.
- A pauses verbal or silent – Pausing before or during a lie is common. Sometimes its a silent pause but it can also be ums and ahs and throat clearing. This could indicate the person is thinking up a lie on the spot if combined with rapid looking around as though they are looking for something.
- Asking you to repeat the question – This can be a stalling tactic if the person is thinking up a lie. Its usually accompanied with them giving a word for word repetition of the question before they begin their answer.
- Uncomfortable body language – Lies can make aperson feel tense and uncomfortable. This can show through in their body language as shifting positions and sudden tensing in the face or body.
- Forced humor – A liar can sometimes become desperate for a joke to defuse the tension they feel. This can lead to unfunny and forced sounding jokes. Usually the joke is accompanied by an attempt to change the subject.
- Forcing changes of subject – A liar may not want to tell their lie if they don’t have to. They may also not have thought the lie through enough to be comfortable with follow up questions. This can cause them to try and force a change in subject that sounds out of place.
For a complete course and full information on becoming a true human lie detector Click Here!

May 31st, 2009 on 1:04 pm
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