WEBVTT

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Truth and deception.

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Lying and telling the truth

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and knowing the difference 
between the two.

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It's something that I think about a lot.

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And it's not that I'm
sort of a cynical, morbid, old guy

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who thinks a lot about lying, but I do,
and I do because it's important.

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(Laughter)

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It's important for us 
in an interpersonal level.

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We have conversations with people;

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we often are concerned

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whether they're being
truthful with us or not.

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It's important for us as a society.

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It's important for us as a world.

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When lies get told to societies,
and they're believed,

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it has a special name;

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it's called propaganda.

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And when propaganda happens,
some really bad things can happen.

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And so I want to talk
about that topic tonight

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from a point of view of science.

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And the science is really interesting

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because it's got
some interesting contradictions

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and, I think, surprising findings in it.

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But I'd like to make this real for you
with a couple of stories,

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just to begin with.

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The first one is about a young man
named Jeffrey Deskovic.

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You can see Jeffrey here;

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he's about 16 years old,

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living the life of the average
American 15- and 16-year-old.

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He was in high school,

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everything was going fairly well,

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and in the fall of 1989,
a tragedy befell his high school

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and one of his classmates.

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A classmate named Angela
went out on a photographic project

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and went missing.

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She was gone for a couple of days.

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And then her body was found,

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and she'd been brutally
raped and murdered.

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Jeffrey took this kind of hard.

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He knew Angela;

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they were not boyfriend and girlfriend,
but they knew each other.

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Angela had been nice to him;

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she'd helped him with his homework.

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And he was deeply affected by her loss.

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He went to the funeral.

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He wrote a letter
that he put on the casket.

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He broke down and cried 
during the funeral.

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This was in a small town in New York.

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The police were very interested
in solving the crime,

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and as they often do,
they went to the funeral.

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They thought Jeffrey
reacted just too much,

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and they became interested in Jeffrey.

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They interviewed Jeffrey
a couple of times,

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but they also interviewed 
a lot of other people.

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And for some reason,

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they just got very interested in Jeffrey.

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One morning, they came to his school,
and unbeknownst to his parents,

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they took Jeffrey,

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and they asked him if he'd come
and take a polygraph test.

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He thought he was going to go down
to the local police station,

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but he was taken some distance away.

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He was introduced to a polygraph examiner.

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And really, there was no intention
of running a real polygraph test that day.

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They wanted to interrogate him.

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The interrogation lasted six hours.

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And at the end of six hours,
Jeffrey was reduced to tears.

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He was on the floor in the fetal position.

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The polygraph examiner,
who had been with him for those six hours,

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gave up,

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and two other detectives came in.

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And they did what you
hear call the "good cop."

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So they were now the helpful police.

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And they tell Jeffrey,

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"If you'll just be honest with us,
we'll get you some treatment,

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you won't have to go to jail."

NOTE Paragraph

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And within about an hour,

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he had confessed
to having raped and killed Angela.

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But they were lying to him.

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They didn't take him to treatment.

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They arrested him 
and charged him with murder.

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He almost immediately 
recanted the confession,

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and said he only did that

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because he thought that was the only way
he was going to get away from the police.

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He eventually went to trial,
was convicted,

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and spent the next 16 years in jail.

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The Innocence Project got involved.

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They discovered that there was
still DNA from the victim

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that the rapist had left behind.

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They, after a long court battle,

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got permission to test that
against the national database,

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which now existed, 16 years later.

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And a hit was found, a positive hit,
on the contributor of the semen.

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And Jeffrey was released
as a wrongfully convicted person.

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He sued and ended up
with quite a bit of money.

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And today, Jeffrey
is actually doing quite well.

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He took some of that money
and created a foundation

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to help wrongfully convicted people.

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And right now he's in law school,

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going to become a lawyer
to represent wrongfully convicted people.

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But here's a young man
who told the truth to the police,

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and he wasn't believed.

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Then he lied to the police
because he gave a false confession,

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and he was believed.

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Then he went to trial,
and 12 people sat in judgment over him,

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and he said that he was innocent,
and they didn't believe him.

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And he went to jail.

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That would be tragedy enough
if it was just Jeffrey.

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But it's not just Jeffrey.

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From the Innocence Project,
we know that there have been

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a quite a number of wrongfully
convicted people.

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About one out of four of them
wrongfully confessed

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to a crime they didn't commit.

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So this is not an unusual, isolated event.

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The other event I want to mention is 9/11.

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And 9/11 is of interest
because those 19 terrorists

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who came to the United States
to attack us,

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every one of them was interviewed
by agents of the United States Government.

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Every one of them,
interviewed at least three times.

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So they were interviewed at the embassy
where they applied for a visa -

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probably interviewed more than once,
given where they came from -

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they were interviewed by Customs

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when they came to the border
of the United States

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to come inside the United States,

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and they were also
interviewed by Immigration.

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Each of them lied three times.

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We didn't catch even one of them.

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Think what a different world
we'd live in today

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if we'd caught even one of them early on

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and talked to them.

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So, that's my interest,
and this is what I do.

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I'm a psychological scientist.

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I study truthfulness and deception
and how you tell the difference.

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And that science, I think, 
is really interesting.

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And I want to give credit to some people

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because I'm gonna talk -
this is not just my work;

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this is work of a group of people
who do research in this area.

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And I want to just give 
some of them credit upfront.

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Charles Bond, Bella DePaulo,
Maria Hartwig, David Raskin, Aldert Vrij.

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And if you're interested,

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those are names
to go look for to read more.

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And the science has
some interesting things in it.

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One is we have interesting
attitudes about lying.

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If you ask people,

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"What makes up good character?

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What do you want to see in people
to think that they're a good person

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and have good character?"

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And near the top of that list
is always "sincere, honest, truthful."

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And at the bottom of that list -
what's bad character?

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The number one or sort
of the numbered last is "liar."

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We don't like liars.

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At least we say we don't like liars.

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But if you go and you look
at people's behavior,

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you find out something really funny,
really interesting, that doesn't fit.

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Because if you look at people's behavior,
they lie frequently.

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If you look at conversations
that last at least 10 minutes,

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the data say we lie in about
one out of every four of those.

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We lie to about one of every three people
we have a conversation with.

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When we talk to our
significant others, our spouses,

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we lie in about one out of ten of those.

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Hmm.

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(Laughter)

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Now, all that lying
might not be a problem

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if we were good at detecting lies.

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And actually if you ask people,
most people think

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they're pretty good at detecting lies,
particularly in people they know well,

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like their children 
or their significant others.

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But again, when you look at the data,

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that's not true.

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And I wish I could tell you
that there is some magic bullet,

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some magic finding from researching.

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Goodness knows there are people out there
who will tell you that

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because they teach seminars,
and they sell books,

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and they train police officers.

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But what the research says

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is that if you look at the ability
of having a conversation with someone

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and detecting whether
they're telling you the truth or not,

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your accuracy is about 54 percent.

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If you flip a coin, it's 50 percent.

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What terrible it is.

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And it turns out there just
really isn't much to find.

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You know, I can ask that question, "Why?
Why are we so bad at this?"

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And I think there are two reasons.

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One has to do with our motivations.

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And there's a very large 
psychological literature

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about how we make decisions,
and I think it's appropriate here.

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And I don't have time to tell you 
all the details of that research,

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but I can capture it for you 
from some literature.

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There was a fantasy book
that was very popular

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about 10 years ago

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written by a fellow named Terry Goodkind;

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it's called The Wizard's First Rule.

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And the wizard's first rule is this:

NOTE Paragraph

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With a little bit of motivation,

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almost anybody can be led
to believe almost anything,

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either because:
1) they want to believe it's true,

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or 2) they're afraid that it's true.

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I want you to think about that 
for a little while and just process that.

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But, you know, that captures
an awful lot of psychological research.

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So that's one problem we have.

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Our motives get in our way [in] how
we interpret the data that we see.

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The other is that it turns out,
it is just really hard to do this.

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There is very little in the body language,
and in the voice, and in the face

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that gives away liars.

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And the reason for that


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is that the very things
that make the liar nervous,

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they're afraid they're going
to get caught -

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it does cause changes;

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people do get anxious about that;

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they do alter their behavior.

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But the truthful person -
think about Jeffrey -

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the truthful person
who is talking to people,

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who he thinks don't believe them,

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you have fear that you're not going
to be believed when you're truthful.

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And the body language you give off
is exactly the same.

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So, where does that leave us?

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Well, science hasn't given up.

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And one approach is technology.

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I've been involved
in one of the technologies

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for most of my adult life,
and that's polygraph testing.

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I was trained as a polygraph tester
and have done that work,

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and although there's a lot
of mythology about polygraph,

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what the science says is that:

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Properly conducted polygraph tests
can be rather accurate.

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In the lab, we can easily get
test accuracies up around 90 percent,

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and there are field studies 
that have replicated that,

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but there's a problem with polygraph.

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One is it requires a skilled
examiner to run the test.

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And a test takes two hours.

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So you need an instrument,
an examiner, and two hours.

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Most of the time, we don't have that;

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it's really expensive in that regard.

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The other problem is
there are police agencies

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like the one that Jeffrey Deskovic
got involved in,

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where they used the polygraph
as a pretense for interrogation.

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And the polygraph
is very dangerous in that setting.

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Recent research has just reported
that [if] you look at the FBI -

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and the FBI is an agency

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that uses polygraph 
as a pretense to interrogate -

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if you are actually innocent,

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and you agree to take
a polygraph from the FBI,

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your chance of not being interrogated
is only 20 percent.

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Four out of five innocent people
get interrogated.

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There are other technologies.

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There are some new ones
that look at the central nervous system.

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So there's EEG and the fMRI.

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And again, they involve 
expensive equipment.

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They've looked interesting 
in the laboratory,

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and they haven't made it out 
into the field.

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There's also a new test


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called an ocular-motor
detection of deception test

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that looks at the eyes.

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So the pupils of our eyes
do get smaller and larger

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as we are processing.

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It is harder to lie
than it is to tell the truth.

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And those tests are around.

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There's some research on them
that looks promising.

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We're waiting for more data
to come in on this.

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And we will need to see
if they'll move out into the field

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and be useable.

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The final area, though, comes back -

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the problem with all those technologies
is that they're expensive.

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You're not going to use that

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if you want to talk
to somebody who works for you,

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or you want to find out

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whether your spouse
is telling you the truth or not.

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And so, are there ways that we can improve
interpersonal detection of deception

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and reading body language,
and face, and all that doesn't work?

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But there are ways we can go about that

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because what the research says
is that what people say

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is way more important
than how they say it.

00:13:59.972 --> 00:14:02.794
So, there's an interview technique 
that's been developed -

00:14:03.124 --> 00:14:07.835
it's a forensic interview technique -
and it's really pretty much common sense.

00:14:08.042 --> 00:14:09.079
But, of course,

00:14:09.079 --> 00:14:11.109
common sense often isn't common.

00:14:12.369 --> 00:14:14.605
And all this technique really does involve

00:14:14.605 --> 00:14:17.958
is letting the person
you're interested in assessing

00:14:17.958 --> 00:14:19.342
tell their story.

00:14:20.852 --> 00:14:22.253
It's called a free narrative.

00:14:22.253 --> 00:14:24.265
So, you literally do just that.

00:14:24.545 --> 00:14:26.107
"Tell me what happened."

00:14:26.677 --> 00:14:28.422
And then you have to stop talking.

00:14:28.932 --> 00:14:31.002
A lot of us find that really hard to do.

00:14:31.222 --> 00:14:33.553
That's not how we have 
conversations with people.

00:14:33.553 --> 00:14:35.484
Conversations usually go back and forth.

00:14:35.894 --> 00:14:39.085
But in this case, you want to just
ask them to tell you their story,

00:14:39.085 --> 00:14:40.916
and then stop talking, and listen.

00:14:42.581 --> 00:14:45.534
Listen carefully, take notes.

00:14:46.534 --> 00:14:47.835
If you have facts,

00:14:49.755 --> 00:14:51.592
there are things you know to be true,

00:14:52.152 --> 00:14:53.549
don't tell them about those.

00:14:53.549 --> 00:14:55.652
If they contradict them,
don't confront them.

00:14:55.973 --> 00:14:57.793
Just listen until they finish.

00:14:58.713 --> 00:15:02.605
And then when they finish,
you strategically use your evidence.

00:15:03.273 --> 00:15:05.329
It's called "the strategic
use of evidence."

00:15:05.329 --> 00:15:06.439
Isn't that surprising?

00:15:06.439 --> 00:15:07.749
(Laughter)

00:15:08.189 --> 00:15:10.064
So the person finishes their story.

00:15:10.274 --> 00:15:11.826
You've been listening carefully.

00:15:11.826 --> 00:15:15.586
You know X happened,
but they never mentioned X.

00:15:16.021 --> 00:15:18.385
And so you go, "Well, I'm confused.

00:15:20.152 --> 00:15:24.735
I know that at this time X happened,
but you didn't talk about that.

00:15:24.735 --> 00:15:25.974
Can you tell me why?"

00:15:26.654 --> 00:15:30.147
And for the innocent person,
most likely it is they just forgot.

00:15:31.194 --> 00:15:34.116
Because when we tell stories
about things we have experienced,

00:15:34.116 --> 00:15:35.455
and they're true stories,

00:15:35.455 --> 00:15:37.916
we often forget to tell about the details.

00:15:37.916 --> 00:15:39.766
We often have to go back and fix it.

00:15:39.766 --> 00:15:42.985
Think about talking to a friend
about something that happened to you

00:15:42.985 --> 00:15:44.045
just recently.

00:15:45.275 --> 00:15:47.991
And you'll know that that's true.
We do that all the time.

00:15:48.031 --> 00:15:49.240
For the innocent person,

00:15:49.240 --> 00:15:52.551
that new evidence is easy 
to incorporate into their story

00:15:52.551 --> 00:15:54.283
because it's in fact true.

00:15:54.283 --> 00:15:55.277
Their story is true.

00:15:55.277 --> 00:15:58.046
"Oh, I just forgot to tell you that.
This is blah blah ..."

00:15:58.046 --> 00:15:59.422
And they fill it in.

00:16:00.252 --> 00:16:03.462
For the liar, it's much more difficult.

00:16:04.282 --> 00:16:05.475
Because the liar -

00:16:05.475 --> 00:16:08.756
you know, the first rule of lying
is you got to keep the lie straight.

00:16:08.756 --> 00:16:11.038
And so they've now told you 
their whole story.

00:16:12.248 --> 00:16:14.662
And now you've given them 
a new piece of evidence.

00:16:14.662 --> 00:16:17.188
They've got to work a lot harder 
to put that back in.

00:16:17.928 --> 00:16:21.488
And if you have more pieces of evidence,
you strategically introduce them

00:16:21.488 --> 00:16:22.739
one at a time.

00:16:23.159 --> 00:16:24.417
And what we find is


00:16:24.677 --> 00:16:29.486
that with people who are outright lying,
their stories eventually collapse

00:16:29.486 --> 00:16:33.484
because they just can't keep up
with the influx of new evidence.

00:16:35.309 --> 00:16:38.200
So, I want to end up with two ideas.

00:16:39.010 --> 00:16:42.917
One is that you have to talk to somebody
and try to make an assessment

00:16:42.917 --> 00:16:44.999
about whether they're being
truthful or not.

00:16:45.259 --> 00:16:46.259
Listen.

00:16:46.259 --> 00:16:51.391
Listen carefully to what they have to say
and remember that what they say

00:16:51.751 --> 00:16:54.167
is far more important
than how they say it.

00:16:54.937 --> 00:16:57.358
Because even innocent people
can look very nervous.

00:16:58.468 --> 00:16:59.658
And the other one is:


00:16:59.838 --> 00:17:02.058
Don't believe anything

00:17:02.838 --> 00:17:05.598
just because you want
to believe that it's true

00:17:06.828 --> 00:17:09.158
or because you're afraid that it's true.

00:17:10.408 --> 00:17:13.347
Our relationships, our lives,

00:17:14.517 --> 00:17:17.114
our country, the world, in fact,

00:17:17.404 --> 00:17:19.024
may well depend upon that.

00:17:19.574 --> 00:17:20.829
Thank you very much.

00:17:20.839 --> 00:17:23.879
(Applause)