8/11/2019 Who Can Catch a Liar

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W h o C a n C a t c h a L ia r

P a u l E k m a n

M a u r e e n O ' S u ll i va n

University o f California San Francisco

University o f San Francisco

The abi l i ty to detect lying was evaluated in 509 people

including law-enforcemen t personnel such as me mb ers

of the U S. Se cret Service Central Intel l igence Agency

Federal Bure au of Invest igation Na t ional Securi ty

Agency Drug Enforcem ent Agency Cal ifornia pol ice and

judge s as well as psychiatrists college students and

working adults. A videotape showed 10 people w ho were

either lying or telling the truth in describing th eir ee lings.

On ly the Secret Service performe d bet ter than chance and

they were s igni ficant ly mo re accurate than al l o f the other

groups. W hen occupational group was disregarded it was

found that those who were accurate apparent ly used di f -

fere nt behavioral clues and had di f ferent ski l ls than those

who were inaccurate.

L i e s o c c u r i n m a n y a r e n a s o f l if e , i n c l u d i n g t h e h o m e ,

s c h o o l , a n d w o r k p l a c e , a s w e l l a s s u c h s p e c i a l c o n t e x t s

a s i n p o l i c e i n t e r r o g a t i o n s a n d c o u r t r o o m t e s t i m o n y . I n

l o w - s t a k e l i e s , t h e l i a r s u f f e r s n o m o r e t h a n e m b a r r a s s -

m e n t i f c a u g h t , b u t i n a h i g h - s t ak e l ie , t h e c o n s e q u e n c e s

f o r s u c c e ss o r f a i l u re m a y b e e n o r m o u s f o r b o t h t h e l i a r

a n d t h e l i a r ' s ta r g e t . E x a m p l e s o f s u c h h i g h - s t a k e l i e s i n -

c l u d e t h o s e b e t w e e n h e a d s o f s ta t e d u r i n g c r is e s, s p o u s a l

l i es a b o u t i n f i d e l i ty , t h e b e t r a y a l o f s e c r e t s t h r o u g h e s -

p i o n a g e , a n d t h e r a n g e o f li es i n v o l v e d i n p e r p e t r a t i n g

v a r i o u s c r i m e s .

L i e s fa i l f o r m a n y r e a s o ns . T h e l i e m a y b e e x p o s e d

b y f a c t s t h a t c o n t r a d i c t t h e l i e o r b y a t h i r d p a r t y w h o

b e t r a y s t h e l i a r 's c o n f i d e n c e . S o m e t i m e s , s u c h o u t s i d e i n -

f o r m a t i o n i s n o t a v a i l ab l e o r is a m b i g u o u s . T h e n t h e l i e

s u c c e e d s o r f a i l s s o l e ly , o r p r i m a r i l y , o n t h e b a s i s o f t h e

l i a r 's b e h a v i o r , w h i c h t h e l e g a l p r o f e s s io n t e r m s

demeanor

( s ee E k m a n , 1 9 8 5 , f o r a d i sc u s s io n o f d i f f e r en t f o r m s o f

l y in g , t h e r o l e o f s t ak e s i n t h e d e t e c t i o n o f d e c ei t , a n d

w h y l i e s fa i l o r s u c c e e d ) .

T w o t y p e s o f e r ro r s m a y o c c u r w h e n t r u t h fu l n e s s

b a s e d o n d e m e a n o r i s j u d g e d : I n a f a ls e n eg a t iv e , a l i a r

i s i n c o r r e c t l y j u d g e d t o b e t r u t h f u l ; i n a f a l se p o s i ti v e , a

t r u t h f u l p e r s o n i s i n c o r r e c t l y u d g e d t o b e l y in g . I n a h i g h -

s t a k e li e, e i t h e r t y p e o f m i s t a k e c a n h a v e s e r i o u s c o n s e -

q u e n c e s . I n d e a l i n g w i t h s u c h s i t u a ti o n s i t w o u l d b e i m -

p o r t a n t - f o r t h e c l in i ci a n, t h e j u r is t , t h e b u s in e s s m a n ,

t h e c o u n t e r in t e l li g e n c e a g en t , a n d s o o n - - t o k n o w h o w

m u c h c o n f i d en c e sh o u l d b e p l a c e d i n ju d g m e n t s b a s e d

o n d e m e a n o r , b y l a y m a n o r e x p e r t , a b o u t w h e t h e r s o m e -

o n e i s l y i n g o r t e l l in g t h e t r u t h .

T h e a n s w e r f r o m 2 0 y e a r s o f r e s e a rc h is n o t m u c h .

I n e v e r y s t u d y r e p o r t e d , p e o p l e h a v e n o t b e e n v e r y a c -

c u r a t e i n j u d g i n g w h e n s o m e o n e i s l y in g . I n t h e u s u a l

s t u d y , o b s e r v e r s a r e g i v e n v i d e o o r a u d i o t a p e s a n d a r e

a s k ed t o j u d g e w h e t h e r e a c h o f a n u m b e r o f p e op l e is

l y i n g o r t e ll i n g t h e t r u t h . A v e r a ge a c c u r a c y i n d e t e c t i n g

d e c e i t h a s r a r e l y b e e n a b o v e 6 0 % ( w i t h c h a n c e b e i n g 5 0 % ) ,

a n d s o m e g r o u p s h a v e d o n e w o r s e t h a n c h a n c e ( s e e r e -

v i e w s b y D e P a u l o , S t o n e , & L a s s it e r , 1 9 8 5 ; K r a u t , 1 9 8 0 ;

Z u c k e r m a n , D e P a u l o , & R o s e n t h a l , 1 9 8 1) . M o s t o f t h e s e

s t u d ie s e x a m i n e d c o l le g e s t u d e n t s, w h o m a y n o t h a v e h a d

a n y s p e c ia l r e a s o n t o l e a r n h o w t o t e ll w h e n s o m e o n e i s

l y i n g . P e r h a p s p r o f e s s i o n a l l ie c a t c h e r s , t h o s e w h o s e w o r k

r e q u i r e s t h e m t o d e t e c t ly i n g , w o u l d b e m o r e a c c u r a t e .

S u r p r i si n g l y , t h r e e s t u d i e s o f p r o f e s s i o n a l l i e c a t c h e r s

d i d n o t f i n d t h i s t o b e s o . K r a u t a n d P o e ( 1 9 8 0 ) f o u n d

t h a t c u s t o m s o f fi c ia l s w e r e n o m o r e a c c u r a t e t h a n c o ll e g e

s t u d e n t s i n d e t e c t i n g d e c e i t i n m o c k c u s t o m s e x a m i n a -

t i o n s. D e P a u l o a n d P f e i fe r ( 1 9 8 6 ) f o u n d n o d i f f e re n c e

b e t w e e n f e d e r a l l a w e n f o r c e m e n t o f f i c e r s , r e g a r d l e s s o f

e x p e r i e n c e , a n d c o l l e g e s t u d e n ts . K o h n k e n ( 1 9 8 7 ) f o u n d

p o l i ce o f fi ce r s d i d n o b e t t e r t h a n c h a n c e w h e n t h e y ju d g e d

v i d e o t a p e s o f c o ll e g e s t u d e n t s w h o h a d l i e d o r b e e n t r u t h -

f u l i n a n e x p e r i m e n t .

I t i s d i f fi c u lt t o d r a w a n y c o n c l u s i o n s f r o m t h e s e

t h r e e s t u d i es o f p r o fe s s i o n a l li e c a t c h e rs b e c a u s e i n n o n e

o f t h e m w a s t h e r e a n y e v i d e n c e t h a t t h e o b s e r v e r s w e r e

e x p o s e d t o b e h a v i o r th a t d i f f e r e d w h e n t h e p e o p l e w h o

w e r e j u d g e d l i ed o r w e r e t r u t h f u l . D e P a u l o a n d P f e i fe r 's

( 1 9 8 6 ) s t u d y i s t h e o n l y e x c e p t i o n , a s t h e y u s e d m a t e r i a l s

t h a t h a d e a r l i e r b e e n s h o w n t o b e s i g n if i ca n t ly d i ff e r e n t

i n o b s e r v e r - r a t e d d e c e p t i v e n e ss ( D e P a u l o , L a n i e r, &

D a v i s , 1 9 8 3 ) . H o w e v e r , t h e d i f f e r e n c e s w e r e s m a l l , a n d

t h e d a t a w e r e n o t a n a l y z e d i n a w a y t h a t w o u l d i n d i c a t e

h o w m a n y l i a r s c o u l d a c t u a l l y b e d i f f e r e n t i a t e d o n t h e

b a s is o f t h e i r o b s e r v a b l e b e h a v i o r . P e r h a p s a c c u r a c y h a s

b e e n m e a g e r a n d n o a d v a n t a g e f o u n d f o r p r o fe s s i o n a l l ie

c a t c h e r s b e c a u s e t h e r e j u s t w a s n o t m u c h i n f o r m a t i o n i n

t h e v i d e o t a p e s t h a t w o u l d a l l ow v e r y g o o d d i s c r i m i n a t i o n

w h e n p e o p l e l ie d .

O u r s i s t h e f i r s t s t u d y t o u s e b e h a v i o r a l s a m p l e s

d r a w n f r o m a s e t o f v i d e o t a p e d i n t e r v ie w s t h a t p r i o r b e -

h a v i o r a l m e a s u r e m e n t s h o w e d d i f f e re d w h e n s u b je c ts l i e d

o r t o ld t h e t r u t h . F a c i a l m u s c u l a r m o v e m e n t s m e a s u r e d

w i t h t h e F a c i a l A c t i o n C o d i n g S y s t e m ( E k m a n & F r i e s e n ,

1 9 7 6 , 1 9 7 8 ) i n c l u d e d m o r e m a s k i n g s m i l e s w h e n t h e

s u b j e ct s l i e d a n d m o r e e n j o y m e n t s m i le s w h e n t h e y t o l d

P a u l E k m a n ' s w o r k i s s u p p o r t e d b y R e s e a r c h S c i e n t is t A w a r d M H 0 6 0 9 2

f r o m t h e N a t i o n a l I n s t i t u te o f M e n t a l H e a l t h .

C o r r e sp o n d e n c e c o n c e r n in g t h i s a r t ic l e sh o u ld b e a d d r e sse d t o Pa u l

E k m a n , H u m a n I n t e r a c t i o n L a b o r a t o r y , U n i v e r s it y o f C a l i f or n i a , 40 1

P a r n a s s u s A v e n u e , S a n F r a n c i s c o , C A 9 4 1 4 3 .

S e p t e m b e r 1 99 1 A m e r i c a n P s y c h o lo g i s t

Copyright 1991 by the A mericanPsychologicalAssociation, nc . 0003-066X/91/ 2.00

Vol. 46, No. 9, 91 3-920

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the truth about their feelings (Ekman, Friesen, & O'Sul-

livan, 1988). Vocal measu rement also distinguished the

lying and t ruthful interviews. There was an increase in

fundamental pitch when the subjects lied. When both the

vocal measure and the two facial measures were com-

bined, it was possible to classify 86 of the subjects cor-

rectly as either lying or being truthful (Ekman, O'Sullivan,

Friesen, & Scherer, 1991). Because there were known be-

havioral differences between the honest and deceptive

samples, our study could focus on the question of how

well observers can detect deception.

We took advantage of opportunities to test a number

of different groups in the criminal justice and intelligence

communi ties to determine whether those who have a spe-

cialized interest, and presumably more experience, in de-

tecting deceit would do better than the usual college stu-

dent observer. We made no hypotheses about the relative

proficiency of he professional lie-catcher groups, although

we hoped that at least one of them might do better than

chance.

In addition to analyzing average accuracy on a

group-by-group basis, as is usually done in studies of de-

ception detection, we also planned to examine accuracy

on an individual basis. The mean accuracy of a group of

observers might be only at chance, but individual ob-

servers might reach either very high or very low levels of

accuracy. Of course, it is also possible that all observers

might perform at or close to chance, but that cannot be

known from the usual method of examining only mean

accuracy.

Because most o f our observers were professional lie

catchers, we were interested in their thoughts and opinions

about lie catching in general, and in their own lie-catching

ability, in particular. DePaulo and Pfeifer (1986) reported

that confidence in one's ability to detect lying was un-

related to actual accuracy, although the federal law en-

forcement officers they studied were more confident than

were college students about their ability to detect decep-

tion. They also reported that amount of experience in

law enforcement was not correlated with accuracy.

Kohnken (1987) also found no relationship between con-

fidence in one's ability to detect lying and actual accuracy.

Unlike DePaulo and Pfeifer, however, he found a signif-

icant negative correlation between experience and ac-

curacy when age was partialed out. We sought to replicate

these findings, and so we asked our professional lie catch-

ers about their confidence in their ability to detect de-

ception before and after taking our test, as well as the

amoun t o f time they had been in their present job.

We also asked our professional lie catchers to de-

scribe the behavioral clues they relied on in making their

judgments. We had two reasons for being interested in

this matter. First, we wanted to test our hypothesis that

those who make accurate judgments, regardless of their

occupational group, would describe different behavioral

clues than those who make inaccurate judgments. On the

basis of our prior analyses of observers' judgments of hese

videotapes when they were exposed to either the verbal,

nonverbal, or combined verbal and nonverbal behaviors

(O'Sullivan, Ekman, Friesen, & Scherer, 1991), and our

findings that there were clues to deceit in the nonverbal

but not in most o f the verbal behaviors we measured (Ek-

man & Friesen, 1976; Ekman et al., 1988; Ekman et al.,

1991). Hypothesis 1 predicted that accurate observers

would report using nonverbal clues more than would the

inaccurate observers.

Our second reason for asking the observers to de-

scribe the behavioral clues they relied on in making their

judgments was to have data that would be relevant to

resolving the question of whether any individual differ-

ences in accuracy we obtained were due to chance. If

those who were highly accurate gave different reasons for

their judgments than those who were inaccurate, it would

argue against the possibility that individual differences in

accuracy were simply chance variations.

In one of our groups, we were also able to test how

well subjects could recognize microexpressions, facial

expressions that last no more than 1/25 of a second. On

the basis of Ekman and Friesen's (1969) proposal that

microexpressions are an important source of behavioral

clues to deceit, Hypothesis 2 predicted a positive corre-

lation between accuracy in detecting deceit and accuracy

in recognizing microexpressions of emotion.

e thod

Observers

Following the publication o f his book

Tel l ing Lies

Ekman

(1985) was asked by a variety of groups that had a profes-

sional interest in lying to conduct a workshop on behav-

ioral clues to deceit. At the start of each such workshop,

the par ticipants were given a test of their ability to detect

deception, which provided the data for this study. None

of the observers had read Ekman's book pr ior to being

tested. The following groups were tested:

1. U.S. Secret Service. All members of the Forensic

Services Division of the Secret Service who were available

in Washington, DC, when the workshop on lying was given

were tested.

2. Federal polygraphers. All part icipants in a Federal

Inter-Agency Polygraph Seminar organized by the Central

Intelligence Agency (CIA) held in the Federal Bureau o f

Investigation (FBI) Academy at Quantico, Virginia, were

tested. This included l0 CIA, 10 FBI, 5 National Security

Agency (NSA), 21 Army, Air Force, or Marine personnel,

and 14 polygraphers employed by other federal agencies.

3. Judges. All of the participants in three courses

on fact finding offered in the midcareer college for mu-

nicipal and superior cou rt judges organized by the Cali-

fornia Center for Judicial Education and Research, and

judges taking a similar course in Oregon, were tested.

4. Police. Those attending the annual meeting of

the California Robbery Investigators Association, which

included city, county, state, and federal law enforcement

officers who specialize in dealing with robbery were tested.

5. Psychiatrists. Texas psychiatrists attending an

annual professional meeting, as well as psychiatrists at-

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tending staff raining sessions in Texas and San Francisco,

were tested.

6. Special interest group. People who enrolled for a

day-long University of California Extension course on de-

ceit were tested. This group included businessmen, law-

yers, accountants, police officers, housewives, social

workers, psychologists, and nurses.

7. Students. For comparison with prior studies, we

also used a sample of undergraduate psychology students

at the University of San Francisco.

Table 1 shows that these groups differed in age and

in sex.

D etec t in g D ecep t ion M easur e

The detecting deception measure consisted of 10 one-

minute samples taken from 10 videotaped interviews,

preceded by a practice item. The videotapes showed a

black-and-white, bead-on view of the full face and body

of each subject.

The observers were told tha t they would see 10 col-

lege-age women, about one half of whom would be lying

to an interviewer as she answered questions about how

she felt about a film she was watching. Each subject would

describe positive feelings she would claim to be feeling

as she watched what she said were nature films. Some

subjects were actually watching such films and would

honesty be describing their feelings. Other subjects would

really be watching a terribly gruesome film that was very

upsetting to them, and they would be lying when they

claimed to be having positive feelings about a nature film.

The observers were told that all of the subjects were highly

motivated to succeed and believed that success in their

deception was relevant to their chosen career. After seeing

each interview, the observers were allowed 30 seconds to

record thei r choice as to whether the subject was honest

or deceptive (more information about the deception sce-

nario is provided in Ekman & Friesen, 1974).

The 10 subjects who were shown to the observers

were selected from a group of 31 subjects who had par-

ticipated in a study of deceit. Behavioral measurements

(described earlier) on all 31 subjects had found that both

facial and vocal measures differentiated the honest from

the deceptive interviews. Most o f those findings had not

been published when the test was given (Ekman et al.,

1988, 1991).

Prior to seeing the videotape, all of the observers

except the college students and the special interest group

responded to the following questions: How good do you

think you are in being able to tell if another person is

lying? Check one of he following: very poor, Ix)or, average,

good, very good. Wha t evidence or clues do you use

in deciding that another person is lying or telling the

truth? (Three lines were given for the observers' hand-

written responses.)

The videotape was then shown. After seeing each of

the 10 persons, the observers recorded their judgmen t by

circling either the word

honest

or the word

deceptive

Fol-

lowing the second and the eighth videotape samples, the

observers were also asked to indicate briefly their reasons

for deciding that the interview was honest or deceptive.

These two items were selected because pilot data indicated

that they differed markedly in difficulty level, although

the subjects in both items were lying. The handwritten

responses were categorized using a coding system devel-

oped in previous research (O'Sullivan & Morrison, 1985)

for categorizing observers' descriptions o f their reasons

for believing that subjects were lying or telling the truth.

This system classified responses into 20 categories with

interrater agreements ranging from 87% to 94%.

After judging all 10 people, the observers were asked

the following questions: How well do you think you did

in telling who was lying?--very poorly, poorly, average,

well, very well. If your job required it, could you lie

and conceal a strong emotional reaction?--yes, probably,

maybe, probably not, no. Additional questions were

asked in some of the groups prior to seeingthe videotape.

These questions, as well as another experimental test tha t

was given to the special interest group, will be described

next.

e su l t s

Wh ich G r o u p I s M o s t Accurate

The observers had judged whether each of the 10 persons

they saw was lying or telling the truth. The observers'

accuracy scores could range from 0 to 10 correct. Because

T a b l e 1

Total Sam ple Size Sex Age and Job Experience in Observer Groups

W o m e n

Observer

g r o u p N ( )

Age

( i n years )

J o b e x p e r i e n c e (i n

years

M S M S

S e c r e t S e r v ic e 3 4 3 3 4 . 7 9 5 . 9 6 9 . 1 2 6 . 6 9

F e d e r a l p o l y g ra p h e r s 6 0 8 3 9 . 4 2 6 . 7 6 6 . 5 4 6 . 1 9

Robbe ry i nves t i ga to r s 126 2 39 21 8 26 14 77 7 15

Judges 110 11 52 64 9 37 11 50 7 77

P s y c h i a t r i s t s 67 3 54 24 10 28

23.63

10 28

S p e c i a l i n t e res t 73 53

43.33

13 44 10 76 9 89

Col lege s t u d e n t s 3 9 6 4 1 9 . 9 0 1 . 7 4

September 1991 American Psychologist 915

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e x a c t l y o n e h a l f o f t h e 1 0 p e r so n s t h e y j u d g e d w e r e l y in g ,

t h e o b s e r v e r w o u l d o b t a i n o n l y a c h a n c e t o t a l a c c u r a c y

s c o r e i f a n o b s e r v e r w e r e t o j u d g e e v e r y o n e t o b e l y in g o r

t o b e t e l l i n g th e t r u t h .

A o n e - w a y a n a l y si s o f v a r i a n c e ( A N O V A ) o n t h e t o t a l

a c c u r a c y s c o r es f o r t h e s e v e n g r o u p s w a s c o m p u t e d . T h e r e

w a s a s i g n i f ic a n t b e t w e e n - g r o u p s e f f e ct , F ( 6 ) = 2 . 0 7 , p