Spotting Lies:Can Humans Learn to Do Better?Bella M. DePaulo

Though cynicism may seem ram-pant, the empirical fact is that mostpeople seem to believe most of whatthey hear most of the time. I haveseen this repeatedly in the studiesmy colleagues and I have conductedon the detection of deception.' Todetermine whether people can sep-arate truths from lies, we show themvideotapes we have made of peoplewe know to be lying or telling thetruth. The topics of these lies andtruths vary widely. For example,sometimes the people on the tapeare talking about their feelings aboutother people they know; othertimes, the speakers are describingtheir opinions about controversial is-sues; in still other studies, they aretalking to an artist about their pref-erences for various paintings, someof which are the artist's own work.When we show people ("judges")these tapes, we ask them to tell us,for each segment that they watch,whether they think the person on thetape (the "speaker") was lying ortelling the truth. We also ask them toindicate, on rating scales, just howdeceptive or truthful the speakerseemed to be. We might also askthem how they think the speakerreally did feel and what impression

Bella M. DePaulo is Professor ofPsychology at the University ofVirginia and recipient of a Re-search Scientist DevelopmentAward from the National Instituteof Mental Health. Address corre-spondence to Bella DePaulo, De-partment of Psychology, GilmerHall, University of Virginia, Char-JottesviMe, VA 22903; e-mail:bmd@yirginia.edu.

the speaker was trying to conveyabout how he or she felt. For exam-ple, it might seem that the speakerwas politely trying to give the im-pression that she liked the personshe was describing, when in fact shedetested that person.

Typically, the tapes that we playfor our judges include equal num-bers of truths and lies. Yet whenjudges watch or hear the tapes, theyalmost always think that many moreof the messages are truths than lies.(One of the rare exceptions was astudy in which the speakers on thetape were experienced salespersonspitching the kinds of products thatthey sell; in that study, the judgesmore often thought that the salesper-sons were lying.^) Similarly, judgestypically believe that the speakersreally do feel the way they are claim-ing to feel. When a speaker claims tolike a painting, the judges are moreinclined to believe that he or shereally does like it than to infer thatthe kind words are a facade to covergenuine loathing.

Despite this compelling inclina-tion to take what other people say atface value, judges are not totallyblind to the differences betweentruths and lies. When we ask them toindicate just how deceptive or truth-ful the speakers seemed to be,judges reliably rate the lies as some-what more deceptive than the truths.The ratings of both the lies and thetruths are almost always on the truth-ful end of the scale; still, the liesseem to the judges to be a little lesstruthful than the truths.^ When westudy humans' ability to detect lies,it is this ability to distinguish truthsfrom lies that we examine.

WOULD PEOPLE BE BETTERLIE DETECTORS IF THEYWERE LBS TRUSTING? i

take each other at their word moreoften than they should. Carol Torisand I did a simple study to seewhether people would be better liedetectors if they were forewarned ofthe possibility that another personmight be lying to them."^ Subjectsplayed the role of interviewers andeither were or were not forewarnedthat the applicants might lie to them.The forewarned interviewers did in-deed become less trusting: Theythought the applicants were gener-ally more deceptive than did the in-terviewers whose suspicions had notbeen aroused. But the suspicious in-terviewers did not become any moreaccurate at distinguishing liars fromtruth tellers. That is, they did not ratethe applicants who really were lyingas any more deceptive than the oneswho were telling the truth.

Robert Rosenthal and I have seenthe same pattern in our studies of sexdifferences in detecting deceit.^ Inthe way that they perceive the liarsand the truth tellers on our video-tapes, men are generally less trustingthan women. For example, whenjudges watch subjects who are talk-ing to an art student about paintings,the male judges are more likely thanthe female judges to think that thesubjects are exaggerating their likingfor the paintings; the women, incontrast, are more inclined to believethat the liking expressed by the sub-jects is genuine. Again, though, menand women do not differ in their abil-ities to distinguish liars from truth tell-ers, that is, to see the liars as relativelyless trustworthy than the truth tellers.

WOULD PCOPLE BE BETTER^ ̂LIE DETECTORS IF THEY HAD

MORE EXPERIENCE AT IT? 0^

To distinguish truths from liesmay require some knowledge or

Copyright © 1994 American Psychological Society

VOLUME 3, NUMBER 1, JUNE 1994

sensitivity about the ways that liesdiffer from truths. Perhaps this sort ofunderstanding comes with endlesspractice at trying to detect deceit.Roger Pfeifer and I studied the liedetection skills of federal law en-forcement officers who had workedfor years at jobs that routinely in-volved attempts to detect deceit.^These officers and undergraduatestudents who had no special experi-ence or training at detecting deceitboth listened to the same audiotapesof students who were lying or tellingthe truth about their opinions aboutcontroversial issues. Across this testof 32 lies and 32 truths, the officerswere no more accurate than the stu-dents at discriminating truths fromlies—they only thought they were.That is, the officers were more con-fident than the students, and theirconfidence increased over thecourse of the test, although their ac-curacy did not. A study of experi-enced customs inspectors told thesame tale: They were no better thanlaypersons at discerning which po-tential "smugglers" to search in amock customs inspection conductedat an airport.'' Similarly, in studies ofspecial groups of people who shouldbe especially skilled lie detectors—members of the U.S. Secret Service,federal polygraphers, judges, po-lice, psychiatrists, and special inter-est groups (e.g., business people andlawyers)—as well as students, PaulEkman and Maureen O'Sullivanhave found generally unimpressivelevels of accuracy at detecting de-ceit.^ Of those groups, only the Se-cret Service did particularly well.

Another kind of experience thatintuitively might seem to predict skillat knowing when someone is lying isthe kind that comes from getting toknow someone over the course of adeepening relationship. Should notdating partners, spouses, and closefriends be much more perceptivethan strangers at spotting each oth-er's lies? Once again, research hasshown that experience is no guaran-tee of sensitivity to deceit. Com-

pared with strangers, relational part-ners are more trusting of each other'struthfulness and more certain thattheir impressions of each other'struthfulness or deceptiveness arecorrect. But unless that trust is sev-ered somehow, they are ordinarilynot more accurate at detecting eachother's deceit.^

Perhaps there is still another wayin which experience might predictskill at detecting deception. Maybeany special skills that people have atdetecting deceit are specific to thekinds of lies they are most experi-enced at hearing—the "I've heardthat one before" phenomenon. Mycolleagues and I already knew fromprior work in our lab that people liedifferently to attractive people thanto unattractive people. Interestingly,they lie more transparently to theformer. We wanted to know wheth-er the lies told to attractive peopleare especially transparent to judgeswho are themselves attractive. Totest this idea, we asked judges whowere themselves either attractive orunattractive to watch tapes of speak-ers who were lying and telling thetruth to attractive and unattractivelisteners.^° The judges, however,could see only the speakers; they didnot even know that the listeners var-ied systematically in attractiveness.Further, the speakers all lied andtold the truth about the same top-ics—their opinions on controversialissues. These were not the stereotyp-ical "gee, what beautiful eyes youhave" kinds of lies. We found, onceagain, that the lies told to attractivelisteners were easier to detect thanwere the lies told to unattractive lis-teners. More important, the lies toldto attractive listeners were especiallyobvious to the judges who werethemselves attractive. The unattrac-tive judges, in contrast, did rela-tively better at detecting the lies toldto the unattractive listeners.

There is other evidence, too, thatskill at detecting lies may be specificto particular kinds of lies. For exam-ple, we have found that the ability to

detect lies when liars are trying tohide their fond feelings is not relatedto the ability to detect lies when liarsare trying to conceal ill wil l. Wehave also found that skill at detect-ing women's lies is unrelated to skillat detecting men's lies.^' There isanother interestingbit of evidence ofspecificity, which comes from astudy in which Miron Zuckermanand his colleagues tried to trainjudges to be more accurate detectorsof deceit.'^ The training procedurewas very straightforward. Judgeswatched a segment in which aspeaker was lying or telling the truth,and then they recorded their judg-ment as to whether the speaker waslying. Next, they were told whetherthe segment was in fact a lie or atruth. This procedure was repeatedfor several lies and truths told by thesame speaker. Judges who were"trained" in this way did indeed be-come better at detecting deception,but only when watching the speakerthey were trained on. Their new andimproved deception detection skillsdid not generalize to different liars.

There is even evidence for speci-ficity at a cultural level. CharlesBond and his colleagues haveshown that both Americans and Jor-danians can distinguish lies fromtruths when judging members oftheir own culture; however, theycannot differentiate each other'struths and lies.^^

HOW DO LIES DIFFERFROM TRUTHS? }

Intuitively, it may seem that thebest way to train people to detectdeceit is to instruct them about thekinds of behaviors that really do dis-tinguish truths from lies and to givethem practice at recognizing suchbehaviors. This approach assumesthat there are known differences be-tween truths and lies, and in factthere are.^

Meta-analyses of the many stud-

Published by Cambridge University Press

ies of cues to deception reported inthe literature indicate that whenpeople are lying, they blink more,have more dilated pupils, and showmore adaptors (self-manipulatinggestures, such as rubbing or scratch-ing) than they do when they are tell-ing the truth. They also give shorterresponses that are more negative,more irrelevant, and more general-ized. They speak in a more distanc-ing way (as if they do not really wantto commit themselves to what theyare saying), and they speak in ahigher pitch. Though people whoare about to tell a lie take more timeto plan what they are about to saythan do people who are about to tellthe truth, the resulting statementstend to be more internally discrepantand more marred by hesitations,repetitions, grammatical errors, slipsof the tongue, and other disfluen-cies. The lies seem rehearsed andlacking in spontaneity.'''

There are, then, some importantbehavioral cues to deception. Butfor a variety of reasons, I am not op-timistic about the prospects of teach-ing these cues directly, despite thefact that some limited successeshave been reported. First, althoughthese findings were obtained acrossa variety of studies, they are quali-fied in important ways. For example,it is possible to divide the studiesinto categories based on whether theliars were more or less motivated togetaway with their lies. When this isdone, it becomes apparent that thecues to deception differ. When peo-ple are more highly motivated to getaway with their lies (compared withwhen they do not care as much),they shift their postures less, movetheir heads less, show fewer adap-tors, gaze less, and even blink lesswhen they are lying than when theyare telling the truth. Their answersare also shorter and spoken moreslowly. The overall impression theyseem to convey is one of inhibitionand rigidity, as if they are trying toohard to control their behavior andthereby overcontrolling it. (It may be

this dampening of expressivenessthat accounts for another counterin-tuitive finding documented repeat-edly in my lab—that is, that peoplewho are most motivated to get awaywith their lies are, ironically, leastlikely to be successful at doing sowhen other people can see or hearany of their nonverbal cues.) Degreeof liars' motivation is just one of thefactors that will qualify conclusionsabout cues to deceit. There will bemany others. For example, cues todeceit should vary with emotionalstate. The liar who feels guilty abouta grave offense, for example, willprobably lie in different ways thanwill a friend bubbling over with gleein an attempt to conceal a surprisebirthday celebration.

Second, all these cues are associ-ated with deceit only probabilisti-cally. There is no one cue that al-ways indicates that a person is lying.And each of the cues that is associ-ated with deceit is also associatedwith other psychological states andconditions. For example, peoplespeak in a higher pitch not onlywhen they are lying but also whenthey are talking to children.

Third, as suggested by the train-ing study in which improvement didnot generalize to different liars, thereare important individual differencesin the ways that people lie. WhenMachiavellian people are rightly ac-cused of lying, for example, theylook their accusers in the eye whiledenying they have lied. It is the"low-Mach" types who conform tothe cultural stereotype about lyingand instead look away. Further, todetermine when a person is lying, itis important to understand that per-son's usual ways of behaving. Forinstance, although halting and dis-fluent speech can be a sign of deceit,there are people who characteristi-cally speak haltingly and disfluently;for them, verbal clutter is unlikely toindicate deceit unless it is even moremarked than usual. Moreover, somepeople may be so skilled at lying thatit is virtually impossible for anyone

to distinguish their lies from theirtruths. In the study of experiencedsalespersons, for example, the samekinds of judges (introductory psy-chology students) who could detectdifferences between the truths andlies of inexperienced liars could seeno differences at all between thetruths and lies told by experiencedsalespersons."̂ Even when the judgeswere given a hint that improved theirlie detection success when theywere observing inexperienced liars(namely, to pay special attention totone of voice), they still could notdifferentiate the salespersons' liesand truths.

Does this mean that it is hopelessto try to refine people's sensitivity tothe differences between truths andlies? Perhaps not. I think peopleknow more about deception than itappears when experimenters askthem directly whether they thinksomeone is lying. Sometimes peoplewho cannot distinguish truths fromlies by their ratings of deceptivenesscan make a distinction by their rat-ings of some other attribute, such asambivalence. Also, when peopletalk out loud as they try to decidewhether someone is lying or not,they sound less confident when themessage they are considering is a liethan when it is a truth; further, theyare more likely to mention the pos-sibility that the message is a lie whenit really is.^'' Interviewers sometimesbehave differently toward liars thantoward truth tellers; for example,they might ask liars more questionsthat sound suspicious.'^ I think,then, that people have implicitknowledge about deception thatthey do not quite know how to ac-cess. Just how they can learn to ac-cess it is the question my studentsand I are currently pursuing.

Notes

1. B.M. DePaulo, J.l. Stone, and C D . Lassiter,Deceiving and detecting deceit, in The Self and So-cial Life, B-R. Schlenker, Ed, (McGraw-Hill, NewYork, 1985).

2. P.]. DePaulo and B.M. DePaulo, Can at-

Copyright © 1994 American Psychological Society

tempted deception by salespersons and customersbe detected through nonverbal behavioral cues?journal of Applied Social Psychology, 19, 1552-1577(1989).

3. In studies in which judges simply indicatewhether they think the speaker was lying or tellingthe truth, and lies and truths occur equally often,accuracy rarely exceeds 60%. A chance level of ac-curacy would be 50% in those sludies.

4. C. Toris and B.M. DePaulo, Effects of actualdeception and suspiciousness of deception on inter-personal perceptions, journal of Personality and So-cial Psychology. 47, 1063-1073 (1984).

5. R. Rosenthai and B-M. DePaulo, Sex differ-ences in eavesdropping on nonverbal cues, journalof Personality and Social Psychology, 37, 273-285(1979).

6. 8.M, DePaulo and R.L. Pfeifer, On-the-jobexperience and skill at detecting deception, journalof Applied Social Psychology, 16, 249-267 (1986).

7. R.E. Kraut and D. Poe, Behavioral roots ofperson perception; The deception judgments of cus-toms inspectors and laypersons, journal of Person-ality and Social Psychology, 39, 784-796 (1980).

8. P. Ekman and M. O'Suliivan, Who can catcha liarMmer/can Psychologist, 46, 913-920 (1991).

9. S.A. McCornackandT.R. Levine, When lov-ers become leery: The relationship between suspi-ciousness and accuracy in detecting deception,Communication Monographs, 57, 219-230 (1990).

10. B.M. DePaulo, J. Tang, and J.I. Stone,Physical attractiveness and skill at detecting decep-tion. Personality and Social Psychology Bulletin, 13,177-187 (1987).

11. B.M, DePaulo and R. Rosenthai, Tellinglies, journal of Personality and Social Psychology,37, 1713-1722 (1979).

12. M. Zuckerman, R. Koestner, and A.O. Al-ton, Learning to detect deception, journal of Person-ality and Social Psychology, 46, 519-528 (1984).

13. CF. Bond, jr., A. Omar, A. Mahmoud, andR.N. Bonser, Lie detection across cultures, journalof Nonverbal Behavior, U, 189-204 (1990).

14. Other behavioral cues to deception havealso been documented, but are based on fewer stud-ies. For example, Ekman and his colleagues showedthat nurses who were pretending to watch a pleasantfilm when the film was actually very gory smiled indifferent ways than the nurses who really werewatching a pleasant film and telling the truth aboutit. The lying nurses were less likely to show smiles ofgenuine enjoyment ("Duchenne" smiles) and more

likely to show "masking" smiles in which traces oftheir negative feelings were discernible. These datawere reported in P. Ekman, W,V. Friesen, and M.O'Sullivan, Smiles while lying, journal of Personal-ity and Social Psychology, 54, 414-^20 (1988).

15. K. Hurd and P. Noller, Decoding decep-tion: A look at the process, journal of NonverbalBehavior, 12, 217-233 (1988).

16. D.B. Buller, K.D. Strzyzewski, and J- Com-stock. Interpersonal deception: I. Deceivers' reac-tions to receivers' suspicions and probing, Commu-nication Monographs, 58, 1-24 (1991).

Recommended Reading

DePaulo, B.M,, Stone, J.I., and Lassiter, C D .(1985), Deceiving and detecting deceit. In The Selfand Social Life, B.R. Schlenker, Ed. (McGraw-Hill,New York).

Lewis, M,, and Saarni, C , Eds, (1993), Lyingand Deception in Everyday Life (Cuilford Press,New York).

The Attentional Blink: TheBrain's "Eyeblink"Kimron L. Shapiro

Attention can be thought of as acognitive mechanism designed toenhance perception of a complexsensory world by selecting certainaspects of perceptual input to pro-cess further. The means by which at-tention accomplishes this goal havebeen studied primarily in the visualand auditory modalities, with a sig-nificant emphasis on the former. Instudying visual attentional mecha-nisms, principal investigators in thefield, such as Posner̂ and Treis-man,^ have concentrated their re-search efforts on one of the major

Kimron L. Shapiro is an AssociateProfessor of Psychology at the Uni-versity of Calgary. Address corre-spondence to Kimron L. Shapiro,Department of Psychology, TheUniversity of Calgary, 2500 Uni-versity Dr., N.W., Calgary, Al-berta T2N 1N4, Canada; e-mail:shapiro@acs.ucalgary.ca.

demands on attention—the ability toselect a particular part of visualspace for further analysis. By visualattention, 1 mean the ability to mon-itor a part of the visual field for achange in stimulation, not the abilityto move one's eyes to a new loca-tion. For example, a baseball pitcherhas such an attentional demandwhen he keeps his eye on the batteras he starts to pitch but must at thesame time monitor the part of his vi-sual field corresponding to first baseto detect if a runner is attempting tosteal second base.

Significant findings from these in-vestigations have concluded (a) thatone can focus attention on a partic-ular region of visual space and bydoing so be faster to detect some-thing occurring in that space than inan equivalent space not being mon-itored, and (b) that a stimulus with aparticular feature of a dimension(e.g., color) can be detected very

rapidly from among a homogeneousfield of stimuli possessing a differentfeature of that same dimension. Forexample, a red-shirted friend is eas-ier to spot in a crowd of people ifeveryone else in the crowd is wear-ing a blue shirt than if the people arewearing shirts of various colors.

Whereas most of the research invisual attention has examined atten-tion over space in a brief moment intime, as just described, some re-searchers have examined attentionover time in a fixed location inspace. '̂'̂ Research in my laboratoryover the past few years has exploredthis latter kind of attention using amodification of a procedure devel-oped by Sperling and his col-leagues.^

RSVP, IF YOU PLEASE

To study this phenomenon, wesimulate the conditions under whicha human might receive very rapidlychanging information over a shortperiod of time, for example, during aseries of rapid saccades (eye move-ments). This simulation technique isreferred to as rapid serial visual pre-

Published by Cambridge University Press