The credibility and reliability of children’s testimony are particularly important in instances where children are called on as primary witnesses in legal proceedings, such as sexual abuse or child custody cases. Although it is expected for children to provide truthful statements about given events, children may also give false reports in these situations for a variety of reasons, and research suggests that adults are relatively poor at detecting such lies. Consequently, despite younger children’s difficulties in concealing their verbal and nonverbal deceptive behaviors effectively, these may not be easily detected by adults. Only with extensive training are adults able to differentiate the verbal statements of a lie or a truth teller at a rate above the chance level. Adults’ ability to detect children’s lies is affected by the developmental level of the child, with younger children having difficulties in maintaining the truthfulness of their statements during follow-up questioning. Although subtle differences are noted in children’s nonverbal behavioral expressions when in a lie- or a truth-telling situation, these discrepancies are small and hard to detect, even for professionals whose job it is to detect a liar. A credible assessment system to detect the lies of young children, especially in light of related factors such as coaching and truth induction, is needed. As more research is undertaken to detect children’s deception, the complexity of the relationships between children’s developmental age, adult biases, and cognitive control of one’s verbal and nonverbal expressive behaviors will delineate a pathway in the direction of accurate detection of children’s lies by professionals and laypersons alike.
Considerable research has been done on children’s unintentional false reports due to repeated or suggestive questioning, children’s memory of events, and children’s ability to distinguish fact from fantasy. Less attention, however, has been given to children’s intentional and deliberate false reports—that is, reports that the individual knows are untrue yet are made with the deliberate purpose of deceiving others. Children may conceal or fabricate a report about an alleged event at the behest of an adult or because they are fearful of the effects their truthful testimony might have, such as upsetting or disappointing loved ones.
Generally, children lie for the same reasons as adults: to avoid punishment or negative consequences, for personal gain, to protect one’s self-esteem, to conform to social conventions of politeness, or to spare another’s feelings. Children’s lie-telling behavior emerges in the preschool years, with lies to escape punishment among the first types of lies children tell. Nevertheless, young children’s ability to deceive is not very good. Their first lies tend to be false denials or short verbal responses (e.g., “No, I didn’t do it”). In the school-age years, children become better able to elaborate and maintain their lies over extended periods. Some evidence exists to suggest that children’s lie-telling abilities are related to their increased cognitive understanding of others’ mental states and their inhibitory control. Furthermore, as children become older, they may naturally lie for a range of motivations. Deciding to lie requires an analysis of the costs and benefits of telling the truth versus lying. School-age children will lie for another (e.g., a parent) when they perceive there are negative consequences for the other and low costs to their self-interest. In circumstances where the consequences of telling the truth might be very negative, children may be more inclined to lie as a tactical strategy in order to avoid those consequences. Moreover, some research suggests that when children are in hostile environments, where they perceive that there are similar negative outcomes whether they are caught in a lie or telling the truth, children are more likely to lie and to be convincing liars, even at a young age.
When telling a lie, it is important to be a convincing liar so as to avoid detection. Thus, it is important to control one’s verbal and nonverbal expressive behaviors. Liars must ensure that what they say and how they present themselves do not contradict. If they are lying about some misdeed, they do not want to appear nervous or shifty so as to raise suspicions in their interrogator or others. Similarly, they will want to make sure that all their verbal statements made after their initial lie do not contradict or reveal information that may make others disbelieve their claims. Thus, lie tellers have to control both their verbal and their nonverbal expressive behaviors, lest they be detected by others. According to studies that examine the detection of children’s false statements, adults make use of such verbal and nonverbal cues to discriminate between the truthful and deceptive statements of children. There are two measurement techniques used for detection of children’s deception: Either adults are asked to detect lies by observing video clips of lie and truth tellers’ reports and to provide judgments regarding the veracity of each report or the occurrences and frequencies of honest and dishonest behaviors are compared with the scores of lie and truth tellers.
Research on detecting children’s truth- and lie-telling behaviors has been conducted in both laboratory and field studies. Laboratory studies have usually used one of two methodologies to detect deception. In the first, children are told to make a false report about an event. These reports are examined using one or both of the following measurement techniques: Trained coders observe the reports for behavioral markers, or video clips of the children’s reports are shown to adults, who are asked to discriminate between the truth and lie tellers. This methodology allows examination of children’s false reports about specifically designed events that may be analogous to legally relevant settings, such as children reporting about a medical examination. However, such reports may be unnatural due to children being instructed to lie or “pretend,” making the act of lying in these cases of very low perceived consequences and thereby unlike certain real-life situations. In the second commonly used laboratory-based methodology, naturalistic situations are created in which children can choose to lie spontaneously about an event, such as committing a transgression (e.g., peeking at a forbidden toy). Video clips of children’s behaviors in these situations are used for detecting the truthfulness of their claims. In these naturalistic lie-telling situations, children may have greater motivation to lie due to the perceived increased risk of consequences of the situation (e.g., getting caught), and thus, they have greater ecological validity. However, current laboratory procedures tend to create situations where children produce only short verbal reports, and the situations created are not necessarily similar to the types of reports given in the legal system. Field study reports, another methodology, use children’s actual reports of events (e.g., sexual abuse) to analyze statements for markers of deception. This methodology has the advantage of being realistic and having ecological validity because actual forensic reports are used. However, unlike the other methodologies where it is known for certain that the child is lying, it is impossible to know for certain which reports are fabricated and which are true.
Children’s Nonverbal Deception Cues
Research has found that when children lie, they reveal subtle signs of their deception in their nonverbal expressive behavior when compared with truth tellers. For instance, in some cases, children will have bigger smiles. However, in other circumstances, lie tellers have been found to display more negative expressive behaviors than do truth tellers. Other behavioral markers of a liar include nonfacial cues such as hand and arm movements, leg and foot movements, and more pauses in speech. Depending on the situation, children may show different behavioral cues to their deception owing to feelings of guilt, fear, or excitement. While these behavioral cues are noted, there are no typical markers of deception across all situations, and any differences found between the nonverbal expressive behaviors of liars and truth tellers are subtle and only detected by trained coders looking for such differences.
Age differences in children’s abilities to control their nonverbal expressive behaviors while in a potentially deceiving situation have been revealed from some studies using adult observers of these behaviors. In particular, evidence is provided in the research literature to suggest that the lies of younger preschool and early-elementary-school children are easier to detect than those of older children or adults. As children become older, they have more muscular control and may be better able to control and suppress nonverbal behavioral cues to their deceit. In other types of studies, however, observers have been found to be at chance level at detecting even young children’s deception. Studies where young children’s deceit has been detected have tended to use methodologies where children were instructed to lie about an event. In studies where children lied spontaneously, adult observers were unable to detect even preschool children’s deceit on the basis of their nonverbal expressive behavior. In addition, studies that have placed children in simulated courtroom settings have found that mock jurors were unable to discriminate between children’s truthful and fabricated reports. In those studies, discriminating markers of children’s deception compared with truth tellers may be masked by the nature of these anxiety-provoking situations. Both laypersons and professionals whose career is centered on detecting deception (e.g., the police, customs officers, social workers, judges) have been found to have difficulties distinguishing child truth tellers from lie tellers. Therefore, in general, children’s deception in naturalistic lie-telling situations is not easily detected on the basis of their nonverbal behaviors.
Children’s Verbal Deception Cues
By and large, research has found that adults may have more success in analyzing children’s verbal cues than their nonverbal cues of deception to detect a liar. Studies that have examined children’s spontaneous lies have found that below 8 years of age, children are not very skilled at maintaining their lies in their subsequent verbal statements. When asked follow-up questions, children tend to reveal information that implicates them in their deception. As a consequence, studies have found that adults can detect young children’s lies based on children’s inability to maintain their lies in their verbal statements. As children become older, in the later elementary school age years, their ability to maintain their lies over extended verbal interchanges and statements increases. As a result, older children’s verbal deception is harder to detect than younger children’s, and adults have difficulty distinguishing deceptive statements from truthful ones.
The ability to verbally deceive may be related to the increased cognitive load that is required to maintain a lie beyond the initial verbal statement. This requires assessing the knowledge of the lie recipient and strategically adapting one’s message to be convincing while simultaneously remembering what one has previously said. Thus, it appears that with increased cognitive sophistication, older children are better at maintaining their lies by employing verbal-leakage control.
The most popular technique for measuring the veracity of children’s verbal statements analyzes components of speech content for certain discriminating features. The Criteria-Based Content Analysis (CBCA) technique was designed to determine the credibility of child sexual abuse reports. CBCA is a systematic assessment technique using transcripts of children’s reports. Coders indicate the presence or absence of 19 criteria assumed to be present in reports of actual events. The method is based on the Undeutsch hypothesis (formulated by the German psychologist Udo Undeutsch) that a statement derived from memory of an actual experience will differ in content and quality from a statement based on the imagination. Field research using CBCA assessment has found that children’s truthful sexual abuse reports received higher scores than those believed to be fabricated. Laboratory studies using CBCA have also found differences between lie and truth tellers. For instance, truth tellers included more details in their reports than lie tellers. Despite only small differences being found, and differences in the criteria that discriminated between children’s true and false reports, CBCA studies received higher accuracy rates at detecting true and fabricated reports than nonverbal studies. Although in general, accuracy rates vary for CBCA analysis, this method has been found to be the most successful in detecting children’s fabricated reports, with most of the rates well above chance level.
There are several caveats of the CBCA technique, especially for use with young children’s statements. First, it is not clear if the CBCA can accurately discriminate very young children’s true and fabricated reports. Some criteria may not be included in very young children’s fabricated reports owing to either cognitive complexity or their having less command of language, potentially making the reports of younger children difficult to classify. Furthermore, using the CBCA criteria, accounts of events familiar to the child are more likely to be considered as true statements than are accounts of events that are unfamiliar.
Therefore, truthful reports of unfamiliar events may not produce high CBCA scores when compared with accounts that are familiarized to children due to repeated experience or talking about the situation, regardless of whether or not the stated events actually occurred. Finally, this technique requires trained coders to detect differences in children’s true and false reports. Studies that have trained laypersons to use CBCA have found mixed results with regard to improved lie detection accuracy. Accordingly, noted differences are not easily detected by laypersons, and use of the CBCA technique may require extensive training before accurate detection is achieved.
A number of other factors can either help or hinder the detection of children’s deception, and as more research is conducted in the area, more factors may be revealed. Children’s lies may be more sophisticated when an adult coaches the child to lie and helps prepare their false statements. Coaching may help children tell more convincing lies as well as maintain their lies over repeated questioning. Inconsistent statements that are revealed through the use of follow-up questions are less likely to be exposed when children are coached on what to say. Coaching is of particular importance in legal cases, because when children lie in court, the possibility exists that they may have been coached by an adult close to them to conceal or fabricate certain information. The handful of studies that have examined this issue have found that children who receive coaching to deceive are not easily detected. Even more, children below 7 years of age who have had coaching in preparing their lies are able to maintain consistency in their verbal deceptive reports.
Another factor that may help adults detect children’s deception is interviewer instructions about the importance of telling the truth (sometimes referred to as “truth induction”). Research has found that asking children about their understanding of truth and lies, as well as having children promise to tell the truth before they are asked about a critical event, helps adults detect children’s lies and truth with an accuracy that is above chance level. It may be that under these circumstances, adults are better able to detect children’s nonverbal deception cues, which may be made more salient due to children’s guilt, or contradictory emotions, after promising to tell the truth and then lying.
Adults’ biases are another factor that may contribute to their perception of a given child as a liar and thus play a role in adults’ overall accuracy of detection. For instance, boys are more likely to be perceived by adults as lie tellers than girls. Conversely, adults tend to have a truth bias, believing in general that children are truthful. In particular, women are more likely to perceive children as truthful than male adult detectors. Finally, some evidence suggests that those who have experience dealing with children in their daily lives (e.g., parents, educators, child care workers, etc.) are better at detecting children’s lies than those who have comparatively little experience with children.
There has been no real examination of children’s lying in high-stakes situations, where the consequences of being caught are serious, thus making them similar to real-life cases. Most studies have had no consequences at all for the child (i.e., when the child is instructed to lie). The most serious high-stakes situations in which children’s lie-telling behavior has been examined have been in relation to denying a transgression that is relatively minor in real life, such as peeking at a forbidden toy or having the child or his or her parent break a toy after its being touched. It may be that in situations where the consequences are perceived as very grave to the child (e.g., being taken away from a close relative), the motivation to lie convincingly may be greater, thus making children’s lies harder to detect.
- Akehurst, L., Bull, R., Vrij, A., & Kohnken, G. (2004). The effects of training professional groups of lay persons to use criteria-based content analysis to detect deception. AppliedCognitive Psychology, 18, 877-891.
- Goodman, G. S., Myers, J. E. B., Qin, J., Quas, J. A., Castelli, P., Redlich, A. D., et al. (2006). Hearsay versus children’s testimony: Effects of truthful and deceptive statements on jurors’ decisions. Law and Human Behavior, 30, 363-401.
- Granhag, P. A., & Stromwall, L. A. (Eds.). (2004). The detection of deception in forensic contexts. New York: Cambridge University Press.
- Leach, A.-M., Talwar, V., Lee, K., Bala, N., & Lindsay, R. C. L. (2004). “Intuitive” lie detection of children’s deception by law enforcement officials and university students. Law and Human Behavior, 28, 661-685.
- Talwar, V., & Lee, K. (2002). Development of lying to conceal a transgression: Children’s control of expressive behavior during verbal deception. International Journal of Behavioral Development, 26, 436-144.
- Talwar, V., Lee, K., Bala, N., & Lindsay, R. C. L. (2006). Adults’ judgments of children’s coached reports. Law and Human Behavior, 30, 561-570.
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