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Interviewing to Detect Deception (grant RES-000-23-0292)
Aldert Vrij
Samantha Mann
Ron Fisher
Becky Milne
Ray Bull
Objectives
We are pleased to report that the project went according to plan. We have carried
out all four experiments as outlined in the proposal. In the original proposal we refer to
four experiments, whereby Experiments 1 to 3 consisted of two parts, an interview part
and a lie detection part. Throughout this report we will refer to these two parts as separate
experiments, and we will therefore discuss the results of seven experiments.
Background
In their police manual, Inbau, Reid, Buckley, and Jayne (2001) 1 present three
strategies aimed at detecting deceit. These are: (i) the focusing on visual cues strategy;
(ii) the Baseline Method strategy; and (iii) the Behaviour Analysis Interview strategy. In
this ESRC project, we examined to which extent those three traditional methods could
discriminate between truth tellers and liars. However, we were pessimistic about their
1 What Inbau et al. (2001) have to say about lie detection is important because their manual is influentialand commonly used by police and military interrogators (Gudjonsson, 2003).
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success, and therefore developed a new strategy to detect deception, called the cognitive
load approach, which we tested in the present project.
Traditional Methods to Detect Deceit
Although in interview settings police detectives could concentrate on both the
suspects behaviour and speech, police manuals typically focus more on behaviour
(visual cues) than on speech related cues to deceit. For example, when Inbau et al. (2001)
discuss the visual (e.g., eye contact, movements), vocal (e.g., response latency, response
length) and verbal (e.g., evasiveness) cues that they claim are related to deception
(Chapter 9), the visual cues section is the largest section. This is remarkable because
deception research has demonstrated that most visual cues, including most of those
discussed by Inbau et al. in Chapter 9, are not reliable indicators of deceit (DePaulo,
Lindsay, Malone, Muhlenbruck, Charlton, & Cooper, 2003). In contrast, vocal cues
(DePaulo et al., 2003) and verbal cues (Masip, Sporer, Garrido, & Herrero, 2005; Vrij,
2005) are more reliable cues to deception. Concentrating too much on visual cues will
therefore hamper lie detection due to the lack of diagnostic cues an observer could rely
upon. Concentrating on visual cues will further encourage the use of stereotypes,
especially when speech is ignored and only nonverbal cues taken into account, as
observers have little to go on (Bond & DePaulo, 2006). Those views are related to how
liars behave (e.g., liars show gaze aversion and fidget) rather than how truth tellers
behave. As a result, concentrating on the visual cues may result in a lie bias, that is the
tendency to judge people as liars. We tested in this project the hypothesis that
concentrating on visual cues will impair lie detection accuracy and will increase a lie bias
(Experiment 7).
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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The basic assumption behind the Baseline Method strategy (examined in
Experiments 5 and 6) is that different individuals show different nonverbal and verbal
responses. This assumption is correct. Some people typically make many movements,
whilst others do not; some people are very talkative, others are not, some tend to look
someone else into the eyes when they speak, other do not, etc. (DePaulo & Friedman,
1998; Vrij, 2000, 2004). In order to control for those individual differences, the Baseline
Method strategy recommends that police officers examine a suspect's natural, truthful,
verbal and nonverbal responses during the small-talk part at the beginning of the
interview, and compare these responses with those shown by the suspect during the actual
interview (Inbau et al., 2001). Differences in behaviour could then be interpreted as signs
of deceit.
This approach is prone to resulting in incorrect judgements because an
incongruent comparison is made. Not only do different people behave differently in the
same situation ( inter personal differences), the same person also behaves differently in
different situations ( intra personal differences) (DePaulo & Friedman, 1998). The
baseline method as proposed by Inbau et al. (2001) fails to take those intrapersonal
differences into account. Small-talk and the actual investigation are fundamentally
different situations. Small-talk conversations are low-stake situations where the suspect's
responses are unlikely to have any negative consequences. The investigative part of the
interview, on the other hand, is a high-stake situation where the suspect's responses are
intensely scrutinised and his/her reactions may easily heighten suspicion. Suspects are
probably aware of this and therefore, not surprisingly, both guilty and innocent people
tend to show different behaviours during small-talk compared to the actual interview
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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(Vrij, 1995, 2006). We thus predicted that the baseline method as proposed by Inbau et
al. would not be effective in discriminating between liars and truth tellers, but were
hoping that a baseline method that did take the intrapersonal differences into account
would be useful.
The Behaviour Analysis Interview (Inbau et al., 2001, examined in Experiments
1 and 2) is a predetermined standardised list of 15 questions, starting with the question:
"What is your understanding of the purpose of this interview?", followed by questions
such as: "Who would have had the best opportunity to commit the crime if they had
wanted to?" Despite its name, behaviour analysis interview, Inbau et al. (2001) predict
differences in both nonverbal and verbal responses between liars and truth tellers.
Regarding the nonverbal responses, Inbau et al. (2001) assume that liars feel less
comfortable than truth tellers in the police interview situation. As a result, guilty suspects
are more likely to cross their legs, shift in their chair, look away and perform grooming
behaviours while answering the BAI questions. Verbal responses should also
discriminate between truth tellers and liars, because, according to Inbau et al. (2001),
interviewees' answers will reflect their different attitudes towards the investigation. Liars
are thought to be less helpful in the interview and do not show the appropriate level of
concern about being a suspect, whereas truth tellers are more likely to offer helpful
information, and show an expectancy to be exonerated.
There is reason to doubt that Inbau's BAI hypothesis will promote effective
discrimination between truth tellers and liars. The basic premise underlying the nonverbal
responses, that liars feel less comfortable than truth tellers in a police interview, is not
universally accepted by the scientific community (National Research Council, 2003). For
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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instance, DePaulo et al. (2003) and Ekman (1985) have argued that in situations where
the consequences of not being believed are severe, not only liars but also truth tellers will
be concerned about not being believed.
Compatible with this view, but refuting Inbau's hypothesis, DePaulo et al.'s
(2003) meta-analysis of nonverbal correlates of deception demonstrated that liars were no
more likely than truth tellers to look away, shift in their chair, cross their legs or make
grooming gestures. In fact, eye contact is not related to deception, and, in direct contrast
to Inbau et al.'s (2001) assumptions, liars tend to decrease rather than increase their
movements (DePaulo et al., 2003). The tendency for liars to decrease their movements
may reflect greater cognitive load borne by liars. Lying is often cognitively more difficult
then telling the truth (DePaulo et al., 2003; Ekman, 1985), and greater cognitive load
results in a neglect of body language, reducing overall animation (Ekman, 1985). Liars'
decreased movements may also be partly attributable to impression management. Liars
are likely to be even more concerned about the impression they make on others than truth
tellers (DePaulo et al., 2003; Vrij, 2000; Kassin, 2005; Kassin & Norwick, 2004). Like
liars, truth tellers are also keen to be seen as truthful. However, truth tellers typically do
not think that this will require any special effort or attention (DePaulo et al., 2003). In
other words, truth tellers more often take their credibility for granted (DePaulo et al.,
2003; Kassin, 2005; Kassin & Norwick, 2004). As a result, liars are more inclined than
truth tellers to refrain from exhibiting excessive movements that could be construed as
nervous or suspicious (DePaulo & Kirkendol, 1989).
This latter impression management explanation (liars put more effort into making
a convincing impression than truth tellers) also raises doubts about the view that guilty
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suspects will be less helpful than innocent suspects. This was the premise underlying the
expected differences in verbal responses to the BAI questions between guilty and
innocent suspects. Both guilty and innocents suspects will probably believe that being
helpful will make a positive impression, but perhaps guilty suspects will be even keener
to make such an impression, because they will take their credibility less for granted.
The combined cognitive load/impression management hypothesis directly
opposes Inbau et al. (2001), and hence predicts that (a) liars' answers should be more
helpful than those of truth tellers and (b) liars' nonverbal responses should appear more
relaxed than those of truth tellers.
The Cognitive Load Approach
Since we had our doubts about the capability of the traditional methods to
successfully discriminate between liars and truth tellers, we proposed a new lie detection
approach (Vrij, Fisher, Mann, & Leal, 2006). This approach is based on the premise that,
in most interviews, lying is cognitively demanding. Several aspects of lying contribute to
this increased mental load. First, formulating the lie itself may be cognitively taxing.
Second, as mentioned above, because liars are typically less likely than truth tellers to
take their credibility for granted liars will be more inclined than truth tellers to monitor
and control their demeanour in order to appear honest to the lie detector. Monitoring and
controlling ones own demeanour should be cognitively demanding. Third, because liars
do not take credibility for granted, they may monitor the interviewer's reactions more
carefully in order to assess whether they are getting away with their lie (Buller &
Burgoon, 1996). Carefully monitoring the interviewer also requires cognitive load.
Fourth, liars may be preoccupied by the task of reminding themselves to act and role-play
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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(DePaulo et al., 2003), which requires extra cognitive effort. Fifth, liars have to suppress
the truth while they are lying and this is also cognitively demanding (Spence et al., 2004).
Finally, while activation of the truth often happens automatically, activation of the lie is
more intentional and deliberate, and thus requires mental effort (Gilbert, 1991; Walczyk,
Roper, Seemann, & Humphrey, 2003).
The premise that lying is cognitively demanding has support from a number of
sources (Vrij, Fisher, Mann, & Leal, 2006). For example, participants in a mock-suspect
experiment directly assessed their own cognitive load during interviews and reported that
lying is more cognitively demanding than truth telling (Vrij, Semin, & Bull, 1996); police
officers who watched videotapes of real life police - suspect interviews thought that the
suspects were thinking harder when they lied than when they told the truth (Mann & Vrij,
2006); and deceiving is associated with activating executive 'higher' brain centres such as
the prefrontal cortex (Spence et al., 2004).
Lie detectors could exploit the differential levels of cognitive load that liars and
truth tellers experience by introducing protocols that introduce additional cognitive load.
Liars, whose cognitive resources will already be depleted by the more demanding act of
lying, will have fewer cognitive resources left over to satisfactorily address the additional
cognitive demand, which will result in more substantial differences between liars and
truth tellers and, subsequently, should facilitate discriminating between liars and truth
tellers. A method to increase cognitive load is recalling an event in reverse order (Fisher,
Brennan, & McCauley, 2002).
We examined the impact of recalling a story in reverse order on lying and lie
detection in Experiments 3 and 4. Based on our assumptions that (i) lying is cognitively
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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more demanding than truth telling, and (ii) recalling a story in reverse order is cognitively
more demanding than telling a story in chronological order, we expected liars to show
more cues to cognitive load than truth tellers, particularly when they were recalling their
stories in reverse order (Experiment 3). In Experiment 4 we showed police officers a
selection of those interviews, and examined their ability to discriminate between liars and
truth tellers in the reverse order and control conditions. Based on the outcome we
anticipated in Experiment 3, we expected truth and lie detection to be superior in the
reverse order condition.
Finally, we examined in what type of interview setting our cognitive load
approach would be most appropriate (Experiment 1). In their analysis of videotaped
police interviews with suspects, Moston and Engelberg (1993) observed two different
styles of starting an interview: Accusatory style and information-gathering style. In the
accusatory style, the interviewer confronts the suspect with an accusation (e.g., "I think
you have committed the crime", "Your reactions make me think that you are hiding
something from me"). In the information-gathering style, the interviewer does not
confront the suspect with an accusation, but rather asks an open question allowing
suspects to describe their actions in their own words (e.g., "Describe in as much detail as
possible what you did between 3pm and 4pm this afternoon?"). We expected
information-gathering interviews to be more appropriate for our cognitive load approach
than the accusatory interviews. First, we expected information-gathering interviews to be
more cognitively demanding than accusatory interviews. In an accusatory interview, the
respondents' replies are likely to be simple, short denials of the accusations (" I didn't do
it", "I am innocent", etc.). By comparison, in information-gathering interviews,
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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respondents are encouraged to provide detailed and lengthy statements about their
activities, which should make their task more cognitively demanding. Second, we
expected information-gathering interviews to result in more verbal cues to deception than
accusatory interviews. The more words there are in the suspect's response, the more
verbal cues there should be to discriminate between liars and truth tellers, simply because
words are the carriers of verbal cues. As information-gathering interviews will generate
longer answers, they will contain more verbal cues to deception than will accusatory
interviews.
Methods
In Experiments 1, 3, and 5 participants (undergraduate students) lied or told the
truth. In Experiments 1 and 3 they lied or told the truth about taking money out of a
wallet (see the two attached articles for full details of the experimental design); in
Experiment 5 they lied or told the truth about having prior knowledge about the number
of dots that appeared on a screen in a count the dots competition. The interviews were
video recorded and the nonverbal behaviours (gaze, gestures (e.g., illustrators,
hand/finger movements and self-adaptors), foot/leg movements, eye blinks, latency
period, pauses, stutters, uhms, speech rate) and speech content (the verbal cues listed in
the Criteria-Based Content Analysis and Reality Monitoring tools) were coded. In
Experiment 1 the participants were interviewed in three different ways (accusatory,
information-gathering, and behaviour analysis interview style) and the impact of the
interview style on behavioural and verbal responses was examined; in Experiment 3
participants recalled their stories in either normal or reverse order; and the impact of this
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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instruction on the behavioural and verbal responses were examined; in Experiment 5 the
behaviour and speech content of liars and truth tellers during the target period (guessing
the number of dots on a screen while having (liars) or not having (truth tellers) been
informed the actual number of dots that appeared on the screen) were compared with the
behaviour and speech content shown by the participants during two control periods,
whereby one control period showed more similarity with the target period (estimating the
number of dots on the screen without having prior knowledge) than the other control
period (small talk at the beginning of the interview). In Experiments 2, 4, and 6,
observers (police officers) were shown a selection of twelve interviews (six truth tellers
and six liars) from Experiments 1, 3 and 5 respectively and were asked after each
interview to judge the veracity of the story-teller. In Experiment 7, observers (police
officers) were shown a selection of fourteen clips from interviews of suspects in their
police interviews (data collected from Mann, Vrij, & Bull, 2002). All participants
observed the same clips but one group saw the video with no audio, another group heard
the audio of the clips but saw no video image. The third (control) group saw the video as
normal. In Experiments 1, 3, and 5, 255 undergraduate students participated: 120 in
Experiment 1, 80 in Experiment 3 and 55 in Experiment 5. In Experiments 2, 4, 6, and 7,
290 police officers participated: 68 in Experiment 2, 55 in Experiment 4, 64 in
Experiment 6, and 103 in Experiment 7.
Results
Concentrating on Visual Cues
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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The truth accuracy, lie accuracy and response bias (B measured with the Signal
detection Theory approach) of Experiment 7 are presented in Table 1. The higher the B
score, the stronger the lie bias was.
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Table 1. Truth Accuracy, Lie Accuracy and Response Bias (B) as a Function of Medium
Exposure
Condition Truth accuracy Lie accuracy BM SD M SD
Visual + audio (N = 35) .59 .1 .70 .1 .21
Visual only (N = 37) .34 .2 .53 .2 .36
Audio only (N = 31) .63 .2 .69 .1 .11
Truth accuracy, lie accuracy and response bias all differed from each other (all
F s > 3.38, all ps < .05, all eta2
> .07. Posthoc tests regarding truth and lie accuracy
revealed that, as predicted, the participants in the visual only condition achieved lower
truth and lie accuracy rates than the participants in both of the other two conditions.
Posthoc tests regarding the response bias revealed that participants in the visual condition
made more lie judgements than participants in the audio condition. These findings
suggest that observing visual cues results in a lie bias, as we predicted. The fact that a lie
bias in the visual only condition did not result in high lie accuracy is interesting. It
appears that more lie judgements (66%) were made when suspects were telling the truth
than when they were lying (47%). This is probably the result of the inaccurate
stereotypical view that observers have about how liars behave (Vrij, Akehurst, & Knight,
2006). For example, although observers believe that liars make more movements than
truth tellers, research has shown that truth tellers typically move more than liars. As a
result, by concentrating on movements, the livelier participants (e.g., truth tellers) will be
classified as liars.
Baseline Method
Analyses of Experiments 5 and 6 are still in progress. Preliminary results show
mixed support for our hypothesis that having a meaningful baseline will facilitate lie
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detection. In Experiment 5 we first examined the behavioural differences between liars
and truth tellers whilst they guessed how many dots there were on the screen (target
period). At a multivariate level, the analysis did not reveal a significant multivariate
effect, F (13, 41) = 1.18, ns. Univariate tests only revealed one significance: Liars paused
longer ( M = .89 per minute of speech, SD = 1.2) than truth tellers ( M = .30, SD = .6), F (1,
53) = 4.60, p < .05, eta 2 = .08. This analysis resembles the task lie detectors face when
they are required to distinguish between truths and lies when no meaningful baseline is
available.
We then carried out a second analysis. This time we detracted the behavioural
scores from liars and truth tellers during the target period from their behavioural scores
during the meaningful control period. This analysis revealed a significant multivariate
effect, F (13, 41) = 2.10, p < .05, eta 2 = .40. Five significant effects emerged at a
univariate level, comprising illustrators, hand/finger movements, self adaptors, gaze
aversion and blinks, all F s > 2.86, all ps < .05, all eta 2 > 05. For each behaviour, liars
displayed larger differences between the target period and the meaningful control period
than truth tellers: Liars decreased their movements more and showed more gaze aversion
than truth tellers. This analysis resembles the task lie detectors face when they are
required to detect truths and lies when there is a meaningful baseline available. In
summary, when a meaningful baseline was available more cues (five) discriminated
between truth tellers and liars than when such a baseline was not available (one).
In Experiment 6 police officers were shown a sample of the liars and truth tellers
from Experiment 5 either with a meaningful baseline (experimental condition) or without
a meaningful baseline available (control condition). Both groups obtained around a 60%
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accuracy rate. A possible explanation why the experimental participants did not
outperform the control participants is that they misinterpreted the diagnostic cues. The
liars showed a decrease in movements, which is typically found in deception research,
whereas observers widely believe that liars increase their movements. Perhaps
experimental participants will outperform control participants if they are informed
beforehand that liars typically decrease rather than increase their movements. We are
going to test this hypothesis in a follow-up experiment.
Behaviour Analysis Interview
The article concerning the Behaviour Analysis Interview experiment (Experiment
1) is attached, so please see that article for further details (Vrij, Mann, & Fisher, 2006a).
The results revealed that liars were less co-operative and appeared more nervous than
truth tellers. These results were consistent with our cognitive load/impression
management hypothesis in direct opposition to Inbau et al.s predictions. When in a
subsequent lie detection experiment (Experiment 2), police officers were shown those
interviews based on the Behaviour Analysis Interview, they performed no better than
chance in discriminating between liars and truth tellers (Vrij, Mann, Kristen, & Fisher, in
press, this article is also attached).
Cognitive Load Approach: Information-gathering Interview Accusatory Interview
Comparison
When we compared participants experiences during the information-gathering
interviews and the accusatory interviews (Experiment 1) we found, as predicted, that
information-gathering interviews were perceived as more cognitively demanding ( M =
4.23, SD = 1.3) than accusatory interviews ( M = 3.36, SD = 1.5), F (1, 76) = 7.36, p < .01,
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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eta 2 = .09 (Vrij, Mann, & Fisher, 2006b). Moreover, information-gathering interviews
resulted, as predicted, in more verbal cues to deceit than accusatory interviews (Vrij,
Mann, Kristen, & Fisher, in press, attached article). The detection of deception
experiment (Experiment 2) did not reveal differences in truth and lie accuracy when the
information-gathering and accusatory interviews were compared (Vrij, Mann, Kristen, &
Fisher, in press, attached article), however, accusatory interviews resulted in more false
accusations (classifying a truth teller as a liar) than information-gathering interviews.
Cognitive Load Approach: The Reverse Order Experiments
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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b l i n k s
1 7 . 3 8
9 . 7
2 7 . 0
7
1 2 . 7
7 . 3 4 * * *
. 1
1 9 . 5
6
9 . 1
2 4 . 7
5
1 2 . 1 2 . 3 4
. 0 6
* p
< . 0
5 , o n e
t a i l e d t e s t
* * p
< . 0
5 , t w o
t a i l e d t e s t
* * * p
< . 0
1 , t w o -
t a i l e d t e s t
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Table 2 reveals the verbal and nonverbal cues that differentiated liars from
truth tellers in the reverse order and control conditions (Experiment 3). The higher the
score, the more frequently the cues occurred. The cues are measured per 100 words
(speech hesitations and speech errors) or per minute of interview (the remaining
cues). As predicted, many more cues to deceit emerged in the reverse order condition
than in the control condition and most of the cues that distinguished liars from truth
tellers in the reverse order condition are signs of cognitive load (all cues except
increase in foot/leg movements and eye blinks).
In Experiment 4, we showed police officers a random sample of these reverse
order and control interviews and examined their ability to detect deceit in those
interviews.
Table 3. Truth Accuracy, Lie Accuracy and Response Bias (B) as a Function of Reverse
Order
Condition Truth accuracy Lie accuracy BM SD M SD
Reverse Order (N = 31) .56 .2 .60 .2 .07
Control (N = 24) .50 .2 .42 .2 -.13
Lie accuracy in the Reverse Order condition was significantly higher than lie
accuracy in the control condition, F (1, 53) = 10.53, p < .01, eta 2 = .17. Lie accuracy in
the Reverse Order condition was significantly above the level of chance, t (30) = 2.68,
p < .05, whereby the lie accuracy in the control condition was significantly below the
level of chance, t (23) = 1.97, p < .05. Although the truth accuracy in the Reverse
Order condition (56%) was also higher than the truth accuracy in the control condition
(50%), this difference was not significant, F (1, 53) = 1.26, ns, eta 2 = .02. The
difference in response bias was not significant either between the two conditions, F (1,
38
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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53) = .87, ns, eta 2 = .02. Neither of the two response biases differed significantly from
zero, t s < 1.59, p > .12. In other words, instructing interviewees to tell their stories in
reverse order led to higher lie accuracy without impairing truth accuracy, without
influencing the response bias.
In summary, the project showed that several methods traditionally used by
investigators to distinguish between truths and lies do not work. However, our new
cognitive load approach showed potential. Cognitive load interview protocols are
designed to make information-gathering interviews more demanding for suspects.
This increased demand has a larger impact on liars than on truth tellers because liars
already find being interviewed more mentally taxing than truth tellers. The result is
that cognitive load interview protocols facilitate discrimination between liars and truth
tellers.
Activities
The results of Experiments 1, 2, 3, 4, and 7 have been presented at European
and American Psychology and Law conferences. The lead applicant, Aldert Vrij,gives detection of deception talks worldwide to both practitioners and scholars
(around ten presentations a year) and the results of this ESRC project have a
prominent place in these presentations. Moreover, Vrij is currently updating his
Telling and detecting lies book (originally published in 2000) and the results of this
ESRC project play an important role in the revised version of his book.
Outputs
The project has so far resulted in four publications (Law and Human Behavior
is the most prestigious Psychology and Law Journal):
Vrij, A., & Mann, S. (2006). Criteria-Based Content Analysis: An empirical test
of its underlying processes. Psychology, Crime, & Law , 12, 337-349.
39
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Vrij, A., Mann, S., & Fisher, R. (2006a). An empirical test of the Behaviour
Analysis Interview. Law and Human Behavior, 30, 329-345.
Vrij, A., Mann, S., & Fisher, R. (2006b). Information-Gathering vs Accusatory
Interview Style: Individual Differences in Respondents' Experiences. Personality and
Individual Differences , 41, 589-599.
Vrij, A., Fisher, R., Mann, S., & Leal, S. (2006). Detecting deception by
manipulating cognitive load. Trends in Cognitive Sciences , 10, 141-142.
One more publication is in press: Vrij, A., Mann, S., Kristen, S., & Fisher, R.
(in press). Cues to deception and ability to detect lies as a function of police interview
styles. Law and Human Behavior .
There are many more publications to come. One paper (Vrij, Mann, Fisher,
Leal, Milne, & Bull) regarding Experiments 3 and 4 has been submitted, and we will
submit a paper regarding Experiment 7 soon. We further received invitations to write
one book chapter about the project (to appear in International developments in
investigative interviewing (Milne, Savage, & Williamson, Eds.), and two entries in theSage Encyclopedia of Psychology and Law (Cutler, Ed.). Experiments 5 and 6 still need
to be written up, as well as the nonverbal data of Experiment 1 and the individual
differences data from Experiments 1 and 2.
Impacts
Throughout this project we worked closely together with the policeconstabularies of Hampshire and Kent and they showed interest in the results. Once
all the data of the project have been fully analysed and written up (we expect this
work to be completed within the next six months) we will contact those constabularies
to discuss the findings. We are planning to discuss the findings also in other
constabularies, and the strong links the co-applicants Milne and Bull have with
40
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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various police constabularies in England and Wales are thereby particularly helpful.
The project has also received interest from several Governments (UK and abroad)
with whom we work on lie detection issues.
Future Research Priorities
We believe that our cognitive load detection of deception approach has
potential and are currently conducting research to refine this approach. Vrij, Fisher,
and Mann received a three-year grant (not from the ESRC) to sponsor these research
activities. The nature of these activities is confidential and cannot be disclosed. Dr
Samantha Mann, who worked as a Research Fellow on the ESRC project, has been
employed as a Research Fellow on this new grant.
Ethics
No ethical considerations have arisen from the project. Students enjoyed
participating because they like to see whether they are good liars. Police officers were
sometimes less enthusiastic, because they did not always see the relevance of the
experiments. The problem is that, as participants allocated to specific experimental
conditions, they lack the overview regarding the aims of the experiments. The
debriefing clarified these issues, but the hypotheses under investigation were
sometimes received with skepticism. Not a single participant, however, withdrew
during the experiments or asked his/her data to be withdrawn after the experiment.Because each experiment demanded so much time from police participants (on
average just over an hour to run) and we generally recruited participants from police
training colleges where courses are highly structured without much free time, it took a
lot of time to accumulate the number of police participants that we did. Therefore we
recruited no more participants then strictly essential to test our hypotheses.
41
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Confidentiality
Nothing reported in this End of Reward Report is sensitive or confidential.
Number of words: 4996
42
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References
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DePaulo, B. M., Lindsay, J. L., Malone, B. E., Muhlenbruck, L., Charlton, K.
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Fisher, R. P., Brennan, K. H., & McCauley, M. R. (2002). The cognitive
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interrogation and confessions, 4th edition . Gaithersburg, Maryland: Aspen Publishers.
Kassin, S. M. (2005). On the psychology of confessions: Does innocence put
innocents at risk? American Psychologist , 60, 215-228.
43
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Kassin, S. M., & Norwick, R. J. (2004). Why people waive their Miranda
rights: The power of innocence. Law and Human Behavior , 28, 211-221.
Mann, S., Vrij, A., & Bull, R. (2002). Suspects, lies and videotape: An
analysis of authentic high-stakes liars. Law and Human Behavior , 26 , 365-376.
Mann, S. & Vrij, A. (2006). Police officers' judgements of veracity, tenseness,
cognitive load and attempted behavioural control in real life police interviews.
Psychology, Crime, & Law , 12, 307-319.
Masip. J., Sporer, S., Garrido, E., & Herrero, C. (2005). The detection of
deception with the reality monitoring approach: A review of the empirical evidence.
Psychology, Crime, & Law , 11 , 99-122.
Moston, S., & Engelberg, T. (1993). Police questioning techniques in tape
recorded interviews with criminal suspects. Policing and Society , 3, 223-237.
National Research Council (2003). The polygraph and lie detection .
Committee to Review the Scientific Evidence on the Polygraph (2003). Washington,
DC: The National Academic Press.Spence, S. A., Hunter, M. D., Farrow, T. F. D., Green, R. D., Leung, D. H.,
Hughes, C. J., & Ganesan, V. (2004). A cognitive neurobiological account of
deception: Evidence from functional neuroimaging. Philosophical Transactions of the
Royal Society of London, 359 , 1755-1762.
Vrij, A. (1995). Behavioral correlates of deception in a simulated police
interview. Journal of Psychology , 129 , 15-28.
Vrij, A. (2000). Detecting lies and deceit: The psychology of lying and its
implications for professional practice . Chichester: John Wiley and Sons.
Vrij, A. (2004). Invited article: Why professionals fail to catch liars and how they
can improve. Legal and Criminological Psychology , 9, 159-181.
44
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC
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Vrij, A. (2005). Criteria-Based Content Analysis: A qualitative review of the
first 37 studies. Psychology, Public Policy, and Law , 11 , 3-41.
Vrij, A. (2006). Challenging interviewees during interviews: The potential
effects on lie detection. Psychology, Crime, & Law , 12, 193-206.
Vrij, A., Akehurst, L., & Knight, S. (2006). Police officers', social workers',
teachers' and the general public's beliefs about deception in children, adolescents and
adults. Legal and Criminological Psychology, 11, 297-312.
Vrij, A., Mann, S., & Fisher, R. (2006a). An empirical test of the Behaviour
Analysis Interview. Law and Human Behavior, 30, 329-345.
Vrij, A., Mann, S., & Fisher, R. (2006b). Information-Gathering vs Accusatory
Interview Style: Individual Differences in Respondents' Experiences. Personality and
Individual Differences , 41, 589-599.
Vrij, A., Mann, S., Kristen, S., & Fisher, R. (in press). Cues to deception and
ability to detect lies as a function of police interview styles. Law and Human Behavior .
Vrij, A., Fisher, R., Mann, S., & Leal, S. (2006). Detecting deception bymanipulating cognitive load. Trends in Cognitive Sciences , 10, 141-142.
Vrij, A., Semin, G. R., & Bull, R. (1996). Insight into behaviour during
deception. Human Communication Research , 22, 544-562.
Walczyk, J. J., Schwartz, J. P., Clifton, R., Adams, B., Wei, M., & Zha, P.
(2005). Lying person-to-person about live events: A cognitive framework for lie
detection. Personnel Psychology , 58, 141-170.
45
To cite this output:Vrij, Aldert (2007). Interviewing to Detect Deception: Full Research Report.ESRC End of Award Report, RES-000-23-0292. Swindon: ESRC