Handbook of Psychology of Investigative Interviewing: Current Developments and Future Directions

by Ray Bull, Tim Valentine, Dr Tom Williamson

  actively observing simultaneously, another important aspect in the accurate

  evaluation of truthfulness.

  Bad habits can also refl ect ignorance about why truths and lies succeed, as

  well as why they fail. For example, although lies sometimes succeed in light

  of factors beyond evaluators ’ control, such as the liar ’ s skill and preparation,

  lies too often succeed because of a lack of knowledge or skill in the recipient

  of the lie. Moreover, lies too often succeed because the recipient of the lie

  wants to believe the liar (i.e., collusion), has no baseline information about

  the liar or has failed to seek collateral information. It is extremely important

  to seek collateral information in order to confi rm or disconfi rm the informa-

  tion provided, particularly in forensic contexts. Understanding one ’ s context

  is also important, as base rates of truth - telling/lying can also have a negative

  impact on one ’ s decision - making, with environments characterized by high

  incident rates of lying (e.g., prisons) resulting in an over - sceptical viewpoint

  and relatively honest contexts (e.g., churches) creating an overly trusting

  attitude.

  Clearly, the more one knows about his/her biases, bad habits and environ-

  mental infl uences, the better able one will be at avoiding bad practices when

  it comes to evaluating truthfulness. However, the best way to counteract these

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  errors is to treat each case on its own merit by looking for behavioural change,

  that is, changes from how a person typically behaves when telling the truth

  (their baseline behaviour). Indeed, viewing changes from baseline is essential

  to the accurate evaluation of truthfulness and is a fundamental aspect to the

  approach introduced in the present chapter.

  Acquiring evidence - based knowledge

  Research suggests that a basic training component for evaluating truthfulness

  consists of the acquisition of empirically - derived knowledge. At the very least,

  individuals should learn about what causes people to lie or tell the truth and

  the typography of truths and lies. Research indicates that there are many moti-

  vations for lying − to avoid punishment, to obtain an underserved reward, to

  protect a loved one, for amusement or to reduce shame (Ekman, 1992 ) − and

  that personality may impact on one ’ s penchant for particular motivations (e.g.,

  Spidel et al ., 2003 ). Research also indicates that lies can vary in terms of their

  content. That is, people can misrepresent their emotional state, their opinion

  on a particular subject, factual information or their future intents. Knowing

  about the different content of lies will assist in the accurate evaluation of

  truthfulness.

  In addition, research has identifi ed different types of lies, including, but not

  limited to, concealment and/or falsifi cation or fabrication, as well as telling

  the truth falsely and the incorrect - inference dodge (Ekman, 1992 ). Concealment

  lies are the simplest form but the most diffi cult to detect because the liar is

  not actively engaging in lying. The outcome is less data to evaluate truthfulness

  than would result from, for example, spinning an elaborate web of deceit.

  Falsifi cation refl ects a deliberate misrepresentation of information. It is harder

  for the falsifi cation lie to succeed in comparison with the concealment lie, as

  the liar has – at the very least – to remember the false statement if asked again.

  No less important, but often forgotten, is the need to learn about what the

  truth looks like. As suggested above, if individuals only know what lies look

  like, they are likely to become susceptible to not believing the truth when they

  see it. As the truth refl ects the end - result of generic emotional and cognitive

  processes, evaluators must acquire this basic knowledge. For example, if inves-

  tigating some past event, individuals should understand how memory works,

  as well as how stress and emotions can disrupt cognitive processes in general

  and memory functioning in particular (see Herv é , Cooper & Yuille, 2007 ). In

  short, it is important to know about the motivations, nature and types of

  truths/lies because they have different emotional and/or cognitive conse-

  quences for the individual and, therefore, will reveal important clues during

  evaluations of truthfulness.

  To understand and appreciate the differential impact of emotions and cogni-

  tions on lying and truth - telling, one should gain knowledge about ‘ the psy-

  chology of lying and truth telling ’ (see Figure 17.1 ). As implied above, in

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  Motivation

  (event / context / personality)

  Truth / lie

  Emotion

  Cognition

  Behaviour

  Change from baseline

  (within and/or across channels)

  Leakage

  Figure 17.1: The psychology of truthfulness

  order to understand the psychology of lying and truth - telling, background

  knowledge on how emotional and cognitive processes typically operate and

  how they impact on certain behavioural channels are required. As Figure 17.1

  depicts, a person

  ’ s motivation to lie or tell the truth must be taken into

  account, as well as the context of the assessment and knowledge about the

  personality of the person being evaluated (if available). These factors interact

  to delineate the particular psychological state of the individual being assessed.

  When an individual lies or tells the truth, there will be emotional and cogni-

  tive consequences, which will, in some way, impact on their behaviour (Yuille,

  1989 ; Ekman,

  1992 ). The impact on their behaviour will be viewed as a

  change from baseline − that is, a change in how the individual typically behaves

  (e.g., in their facial expression, eye gaze, body language) and/or contradictory

  behaviours that occur simultaneously or in close succession (e.g., head shake

  indicating ‘ no ’ but answering ‘ yes ’ ). When someone demonstrates a change

  from baseline via a behavioural (i.e., observable) channel, the result is leakage.

  That is, in effect, the change from baseline leaks out (Ekman, 2003 ; Herv é ,

  Cooper & Yuille, 2008 ). Identifying leakage via active listening and observing

  is crucial to the process of evaluating truthfulness. That is, behavioural change

  is not random; it occurs for a reason (see below for further details).

  Skill acquisition

  In addition to empirically - based knowledge, the literature indicates that train-

  ing in evaluating truthfulness should involve the development of specifi c,

  Evaluating Truthfulness

  315

  evidenced - based skills. The knowledge base discussed above would form the

  foundation for the development of certain skills and, more importantly, for

  the appropriate application of these skills. One skill involves identifying leakage

  (i.e., emotional or cognitive leakage), that is, how lies leak out through non-

  verbal channels (e.g., facial expressions and body language) and verbal chan-

  nels (e.g., verbal style and content). In order to identify lea
kage, attention

  should focus on what people do and say and how they do it and say it. In

  other words, for leakage to be identifi ed, ‘ active listening ’ and ‘ active observ-

  ing ’ must occur simultaneously. Through active listening and observing, emo-

  tional and cognitive leakage can be observed through a number of observable

  behavioural channels.

  Emotional leakage can be viewed through a number of observable channels,

  such as the face or voice and via body language. The face, however, is the

  primary and clearest channel through which to observe emotional reactions,

  and it is also the most researched (for a review, see Ekman, 2003 ). Ekman has

  demonstrated that there are seven universal facial expressions of emotion that

  can be observed

  − fear, sadness, disgust, happiness, surprise, contempt,

  anger − research suggests that they appear in all cultures regardless of language.

  It has been shown that, by developing the skill of observing the facial repre-

  sentations of these seven basic emotions, one ’ s ability to identify different

  emotional states accurately can be increased (Frank & Ekman, 1997 ).

  Most of the time, when a facial expression of emotion is observed, it is a

  macro - expression, that is, it is full and relatively long

  - lasting (

  > 1 second)

  (Ekman, 2003 ). However, macro - expressions of emotions are usually ignored

  due to verbal overrides (see above) and, more importantly, are relatively easily

  faked. In addition to facial macro - expressions of emotion, subtle and micro -

  expressions have been identifi ed (Ekman, 2003 ). In general, subtle or micro -

  expressions of emotion refl ect attempts to conceal the emotion to one ’ s self

  or to others (Ekman, 2003 ). A subtle expression is a partial facial expression

  of emotion resulting from one ’ s inability to fully control emotional expression.

  A subtle expression may also occur when an emotion is just beginning to

  develop. Micro - expressions are full expressions of emotion that occur fl eet-

  ingly, typically between 0.04 and 0.2 of a second (Ekman, 2003 ). Most people

  miss micro - expressions in their day - to - day interactions, however, training in

  their detection in the context of active observing can improve individuals ’

  ability to detect them (Frank & Ekman, 1997 ). Training can also improve an

  individual ’ s ability to detect subtle expressions. Although identifying micro -

  and subtle expressions can inform individuals as to the emotional state of

  others, on their own, they cannot inform individuals of why that emotional

  state is being felt (see below).

  Another channel that has been heavily researched is verbal content (Yuille,

  1988 ), a domain in which cognitive leakage could be observed. Although

  cognitive reactions to lying and truth - telling can be observed across a number

  of behavioural channels, verbal content is, however, the primary and clearest

  channel with which to observe such cognitive reactions. The analysis of verbal

  content stems, in part, from the assumption that, in general, it takes more

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  Handbook of Psychology of Investigative Interviewing

  mental effort to lie than it does to tell the truth. That is, lying causes more

  cognitive load than does truth - telling (Yuille, 1989 ; Vrij & Granhag, 2007 ).

  Indeed, as a liar does not have a memory of a false account of an event, it

  takes more cognitive capacity for him or her to keep the story consistent. In

  contrast, a truth - teller can rely on his or her memory when relating an event.

  Thus, an increased cognitive load is one of the factors that may betray a liar.

  Based on factors associated with memory and cognition, such as cognitive load,

  Undeutsch (1989) formulated a hypothesis, which essentially posits that mem-

  ories of experienced events differ in quantity and quality from memories of

  invented experiences. The Undeutsch hypothesis formed the basis of Statement

  Validity Analysis (SVA), which has received empirical support (Horowitz,

  1991 ). The core of SVA is CBCA, criteria that research has demonstrated to

  be more likely to be found in credible accounts as opposed to non - credible

  accounts of events (e.g., Lamb et al ., 1997 ; Colwell, Hiscock & Memon,

  2002 ). Research indicates that CBCA is a complex qualitative assessment pro-

  cedure and should be combined with the other skill - based components to

  evaluating truthfulness (Cooper et al ., 2007 ; Cooper, Herv é & Yuille, 2007 ).

  Unlike many other skills associated with the evaluation of truthfulness (e.g.,

  the ability to detect micro - expressions), CBCA focuses on factors associated

  with truth - telling and, therefore, nicely complements other approaches or skills

  that focus on detecting clues associated with lying.

  Although there is extensive research support for facial expressions and verbal

  content in evaluating truthfulness, other important evolving areas include

  reading the face together with body language and detecting changes in the

  voice and verbal style (Ekman et al ., 1991 ). In terms of the former, changes

  in body language are complex and can betray both the emotional and cogni-

  tive aspects of lies. For example, research indicates that knowing the baseline

  of use of different types of gestures (e.g., emblems, illustrators and manipula-

  tors) is important to detect change in these gestures (Ekman et al. , 1978 ;

  Ekman et al ., 1991 ). For example, one person may show a decrease in illustra-

  tors (i.e., hand movements used to illustrate speech) when he or she has an

  increase in cognitive load, yet another person may show an increase in illustra-

  tors when their cognitive load has been taxed. Detecting change within a given

  individual is crucial to the evaluation of truthfulness.

  In terms of detecting changes in the voice, this can betray emotional and,

  to a lesser extent, cognitive aspects of lying (Ekman et al. , 1978 ; DePaulo,

  1992; 1994 ). For example, the voice may get softer when someone is lying,

  however, a softer/lower voice can also refl ect sadness, which highlights the

  importance of always considering alternative hypotheses before making a deci-

  sion about the signifi cance of what has been heard and/or observed (i.e., using

  a hypothesis - testing approach). As indicated above, some companies advertise

  voice - based lie detectors but, as these devices measure changes in voice pitch,

  they are not lie detectors but change detectors. Change can be due to lying

  but can also be due to many other factors, which once again highlights the

  need to utilize a hypothesis - testing approach.

  Evaluating Truthfulness

  317

  Finally, it has been demonstrated that verbal style can leak both emotional

  and cognitive aspects of lying. Such would include increased duration of pauses

  or greater use of fi lled pauses, changes in pronoun use or responding without

  answering the question. For example, if a suspect in a robbery, during the

  recounting of his or her version of events in the fi rst person pronoun, pauses

  at the point of entering the location of the robbery and then drops the use of

  the fi rst person pronoun ( ‘ I ’ ), the change may refl ect a lie of omission
− more

  may have transpired than what was being revealed. It should be noted, however,

  that the change does not imply that the person committed the robbery. Rather,

  it highlights a point in the account that should be reviewed again, as a signifi -

  cant change in verbal style has been observed (i.e., a signifi cant change from

  baseline verbal style).

  Although implied throughout this chapter, it is nevertheless important to

  highlight the reality that none of the aforementioned channels are in and of

  themselves clues to deception; they are clues of importance. As noted above,

  changes in these channels simply refl ect a change in emotional and/or cogni-

  tive load. At times, the channels may be revealing different messages, thereby

  suggesting internal confl ict. These changes and inconsistencies are important

  in conducting evaluations of truthfulness, not because they necessarily reveal

  lies but because they reveal topics that need further exploration; hence the

  need for a method by which to conduct such evaluations.

  Method

  Research and practice suggest that an evidence - based method that helps evalu-

  ators organize the information collected and, thereafter, make an informed

  decision is a vital component of clinical decision

  - making in general (see

  Monahan et al ., 2001 ) and evaluating truthfulness in particular (Herv é , Cooper

  & Yuille, 2008 ). At the very least, this method should promote critical think-

  ing − the objective evaluation of data in the context of multiple hypothesis -

  testing. We believe that using a ‘ single case design ’ can help evaluators achieve

  this goal. With this design, each case can be evaluated on its own merits. This

  design not only advocates collecting data rich in quantity and quality (as

  detailed above), it also emphasizes the importance of considering multiple

  hypotheses; that is, using a hypothesis - testing approach, both when consider-

  ing the meaning of particular data points and when making overall decisions.

  The evaluator is encouraged to check and double - check his or her hypotheses

  against the available evidence − changing/updating hypotheses as the evidence

  to support the hypotheses changes. Even when the issue at hand appears to

  be quite simplistic, multiple hypotheses should be considered. As noted above,