How to spot a liar

It’s a hundred years since the polygraph was invented, the machine that is supposed to be able to tell if someone is telling lies or not.

It would seem that it’s not very good at telling. In fact, with a little training, you could do the job more accurately yourself.

What’s interesting about lying is that it is a vital part of the society we live in. When someone asks you “How are you?” it’s not the done thing to say how bad things are, even if they are. The correct, polite response is to say that you are fine. Sometimes that’s a lie.

So we all do it.

Who is best at lying?

It’s the charming smooth-talkers. This is contrary to what you might think. Perhaps it’s why people get taken in.

How can you tell if someone is lying?

It’s hard. But one good way to determine the truth is through careful questioning. Not the kind of Sweeney-type shouting and threatening:
“It was you that killed him, wasn’t it?”

One of the most effective techniques is to get people to tell you what happened in reverse order. That’s because it’s so much harder to get all the details right when you are having to make them up backwards.

Lying is quite a difficult process and demands quite a level of skill.

Being nervous

This is not a good indication of lying – truth-tellers also get nervous.

Training

Training can help you to become better at spotting lies.  There are clues, according to the research of Stephen Porter’s Forensic Psychology Lab at Dalhousie University.

There are some muscles in your face that you can’t control and those are the ones that give you away.

It seems that small flashes of your true emotions break through, though sometimes not for very long, so being able to watch a video recording of the answers can help a lot. If you haven’t got one handy, use questions about what happened.