I did not have sexual relations with that woman, Ms. Lewinsky.

OK.

Studies show that people who are over determined in their denial will resort to formal rather than informal language.

We also heard distancing language – "That woman".

We think liars fidget all the time, well guess what: They're known to freeze their upper bodies when they're lying.

We think liars won't look you in the eyes.

Well guess what: they look you in the eyes a little too much.

We think warmth and smiles convey honesty, sincerity.

Can you all spot the fake smile here?

You can consciously contract the muscles in your cheeks but the real smile's in the eyes.

The crow's feet in the eyes, they cannot be consciously contracted.

Can you tell what's happening in a conversation?

Can you start to find the hot spots to see the discrepancies between someone's words and someone's actions.

Attitude is by far the most overlooked but one of the most telling of indicators.

An honest person is going to be cooperative. They're going to be on your side; they're going to be enthusiastic.

They're going to be willing and helpful in getting you to the truth.

And if you ask someone honest: "What should happen to whoever did forge those checks?"

An honest person is much more likely to recommend strict rather than lenient punishment.

Now let's say you're having that exact same conversation with someone deceptive.

That person may be withdrawn, look down, lower their voice, pause and then they're going to tell their story in strict chronological order.

And what a trained interrogator does is they come in,

and in very subtle ways, they will ask that person to tell their stories backwards and then track which questions produce the highest volume of deceptive tells.

We rehearse our words but we rarely rehearse our gestures.

We say yes, we shake our heads no.

We tell very convincing stories, we slightly shrug our shoulders.

Now there are going to be times when someone makes one expression while masking another that just kind of leaks through in a flash:

Your new joint venture partner might shake your hand, celebrate, go out to dinner with you and then leak an expression of anger.

There's one I can teach you that's very dangerous and easy to learn.

And that's the expression of contempt.

When anger turns to contempt, you've been dismissed.

It's associated with moral superiority and for that reason it's very very hard to recover from.

It's marked by one lip corner pulled up and in,

and in the presence of contempt, look the other way, go the other direction, say no thank you.

I'm not coming up for just one more night cap, thank you.

We know liars will shift their blink rate, point their feet towards an exit.

They'll alter their vocal tone, often making their vocal tone much lower.

Thank you.