Training in the Strategic Use of Evidence technique: Improving deception detection accuracy of American law enforcement officers

The Strategic Use of Evidence (SUE) approach is a framework for planning and executing suspect interviews with the aim of facilitating judgments of truth and deception. US law enforcement officers (N = 59) either received training in the SUE approach or did not. Each officer interviewed a mock suspect (N = 59) who had either committed a simulated security breach or had completed a benign task. The officers who received SUE training interviewed in line with the training: They questioned the suspect systematically, withheld the evidence and critical case information until after questioning, and relied on statement-evidence inconsistency to detect deceit. Consequently, SUE-trained interviewers achieved a higher deception detection accuracy rate (65%) compared to untrained interviewers (43%).     

Thermal Imaging as a Lie Detection Tool at Airports

We tested the accuracy of thermal imaging as a lie detection tool in airport screening. Fifty-one passengers in an international airport departure hall told the truth or lied about their forthcoming trip in an interview. Their skin temperature was recorded via a thermal imaging camera. Liars’ skin temperature rose significantly during the interview, whereas truth tellers’ skin temperature remained constant. On the basis of these different patterns, 64% of truth tellers and 69% of liars were classified correctly. The interviewers made veracity judgements independently from the thermal recordings. The interviewers outperformed the thermal recordings and classified 72% of truth tellers and 77% of liars correctly. Accuracy rates based on the combination of thermal imaging scores and interviewers’ judgements were the same as accuracy rates based on interviewers’ judgements alone. Implications of the findings for the suitability of thermal imaging as a lie detection tool in airports are discussed.     

Eliciting Cues to False Intent: A New Application of Strategic Interviewing

This article examined how to elicit cues to deception when a suspect is asked both about his/her intentions and his/her corresponding past planning, and when the investigator holds evidence on the suspect’s planning activities. In a new experimental set-up accommodating the main characteristics of intent, participants (N = 120) either planned a criminal or a non-criminal act. They were intercepted before completing the planned act. Each participant was interviewed in accordance with one of three interview techniques: Early Evidence disclosure or one of two versions of the Strategic Use of Evidence (SUE) technique. All the interviews were transcribed and scored for consistency. As predicted, the liars were perceived as having a higher degree of inconsistency for two of the three relevant comparisons (Statement on Planning–Evidence on Planning; Statement on Intent–Evidence on Planning). Furthermore, using the evidence strategically resulted in differences between liars and truth tellers being magnified, as predicted. This article advances previous findings in showing that by interviewing strategically with respect to the evidence, it is possible to elicit reliable cues to deception when a suspect is asked about intentions and corresponding planning activities.     

The devil is in the detail: deception and consistency over repeated interviews

ABSTRACT

Research indicates that truthful statements typically contain more details than fabricated statements, and that truth tellers are no more consistent than liars over multiple interviews. In this experiment, we examine the impact of (i) multiple interviewers and (ii) reverse order recall on liars’ and truth tellers’ consistency and amount of reported detail over repeated recall attempts. Participants either took part in a mock crime (lying condition) or an innocent event (truth telling condition) which they were subsequently interviewed about in two separate interview phases. Truth tellers provided more details overall, and more reminiscent details than liars. There were no differences between veracity groups for the number of omissions made or repetitions reported. Despite the popular belief that inconsistency is a cue to deception, we found little support for the notion that consistency (or lack of consistency) offers a diagnostic cue to deception. We found little evidence that switching interviewer or recalling in reverse order induced inconsistencies in liars. In fact, due to the number of reminiscent details in truth tellers’ accounts, our findings suggest that accounts provided by liars tend to be slightly more consistent than those provided by truth tellers. Materials for this paper can be found at osf.io/hgvmk/.     

Exploring liars’ strategies for creating deceptive reports

Purpose. Most past research on detecting deception has relied on the assumption that liars often fabricate a story to account for their whereabouts, whereas truth tellers simply recall an autobiographical memory. However, little research has examined whether liars, when free to choose the topic of their own reports, will actually choose to fabricate information rather than use a different strategy for constructing their lies. We describe two studies that evaluated liars’ strategies for selecting the content of their lies when given the freedom to choose whatever content they desired. Method. In Studies 1 (N= 35) and 2 (N= 22) participants (a) described a truthful story in order to identify a salient event, then (b) lied about the event, and finally (c) described their strategies for choosing the content of the reported lies. Results. Liars overwhelmingly chose to report a previously experienced event for the time period they were to be deceptive about (67% and 86% in Studies 1 and 2, respectively). The majority of discrete details reported were experienced, occurred relatively frequently, occurred relatively recently, and were typical or routine. Conclusions. These findings have significant implications for the development of cognitive‐based interventions for detecting deception. In particular, some methods of deception that rely on content analysis may be ineffective if liars choose to report previous experiences rather than outright fabrications.     

Training Police Investigators to Interview to Detect False Intentions

This study is the first to investigate police investigators’ adherence to, and the effectiveness of, a training program for detecting true and false intentions. Experienced police investigators (N = 53) were either trained or not trained in how to interview to discriminate between true and false intentions. All investigators interviewed mock suspects (N = 53), of which half lied and half told truth about their intentions. Both subjective and objective measures showed that the trained investigators interviewed in line with the training received. That is, a large proportion asked about the planning of the stated intentions. Noteworthy, none of untrained investigators reported to have posed such questions for strategic purposes. The trained investigators reached a higher detection accuracy level (65 %) than their untrained colleagues (55 %), however not significantly. Given that the investigators adhered to the training, this training package is a viable starting point for developing more effective training programs.     

Interviewing to Detect Deception: When to Disclose the Evidence?

Research shows that there are few objective cues to deception. However, it may be possible to create such cues by strategic interviewing techniques. Strategic Use of Evidence (SUE) is one such technique. The basic premise of the SUE technique is that liars and truth tellers employ different counter-interrogation strategies, and that the evidence against the suspect can be used to exploit these differences in strategies. This study examined the effect of the timing of evidence disclosure (early vs. late vs. gradual) on verbal cues to deception. We predicted that late disclosure would be most effective in differentiating between liars and truth-tellers, and that cues to deception in the gradual disclosure condition would progressively disappear due to the suspects’ realization that evidence against them exists. That is, we expected that liars in the gradual presentation condition would become more consistent with the evidence over time. A sample of 86 undergraduate students went through a mock-terrorism paradigm (half innocent, half guilty), and were subsequently interviewed using one of three disclosure strategies: early, gradual, and late disclosure. We measured statement-evidence inconsistencies as cues to deception . Results supported our predictions in that cues to deception were most pronounced in the late disclosure condition. Contrary to our expectations, the results suggested that presenting the evidence gradually may put innocent suspects at a higher risk of misclassification as they seem to adopt a strategy that is more similar to guilty suspects.     

To act truthfully: Nonverbal behaviour and strategies during a police interrogation

Abstract

In an experiment, nonverbal indicators of deception in police interrogations of mock crimes were examined. Both vocal and nonvocal behaviours were scored. Thirty participants were subjected to long interrogations (over 9 minutes) conducted by 30 experienced police officers, asked to interrogate as they normally do. Although the liars reported being significantly more nervous, and found the task more strenuous than the truth tellers, no differences in the nonverbal behaviours scored were found. In an analysis of the strategies employed, both truth tellers and liars were found to try to not make excess movements. The principal verbal content strategy for the liars was to keep the story simple, and for truth tellers to keep the story real. The reasons why, in this demanding situation, the truth tellers and liars could not be distinguished by their nonverbal behaviour are discussed.     

You cannot hide your telephone lies: Providing a model statement as an aid to detect deception in insurance telephone calls

Deception research regarding insurance claims is rare but relevant given the financial loss in terms of fraud. In Study 1, a field study in a large multinational insurance fraud detection company, truth telling mock claimants (N = 19) and lying mock claimants (N = 21) were interviewed by insurance company telephone operators. These operators classified correctly only 50% of these truthful and lying claimants, but their task was particularly challenging: Claimants said little, and truthful and deceptive statements did not differ in quality (measured with Criteria‐Based Content Analysis [CBCA]) or plausibility. In Study 2, a laboratory experiment, participants in the experimental condition (N = 43) were exposed to an audiotaped truthful and detailed account of an event that was unrelated to insurance claims (a day at the motor races). The number of words, quality of the statement (measured with CBCA), and plausibility of the participants' accounts were compared with participants who were not given a model statement (N = 40). The participants who had listened to the model statement provided longer statements than control participants, truth tellers obtained higher CBCA scores than liars, and only in the model statement condition did truth tellers sound more plausible than liars. Providing participants with a model statement is thus an innovative and successful tool to elicit cues to deception. Providing such a model has the potential to enhance performance in insurance call interviews, and, as we argue, in many other interview settings.     

Two heads are better than one? How to effectively use two interviewers to elicit cues to deception

Background. We examined the effect of a second interviewer's demeanour on cues to deception. We predicted that a supportive demeanour would be the most beneficial for eliciting verbal cues to deceit, as it would encourage truth tellers, but not liars, to say more. In addition, we examined the extent to which interviewees deliberately made eye contact with the interviewers. Liars take their credibility less for granted than truth tellers, and therefore have a greater drive to be convincing. Liars are thus more likely to monitor the interviewer to determine if the interviewer appears to believe them. Method. Participants appeared before two interviewers: the first asked all the questions and the second remained silent. The second interviewer exhibited either a supportive, neutral, or a suspicious demeanour. Results. Truth tellers provided significantly more detail than liars, but only in the supportive second interviewer condition. The effect of a second interviewer's demeanour on detail was perhaps remarkable given that the interviewees hardly looked at the second interviewer (less than 10% of the time). Liars displayed more deliberate eye contact (with the first interviewer) than truth tellers did. Conclusions. A supportive second interviewer has a positive effect on interviewing. We discuss this finding in the wider contexts of investigative interviewing and interviewing to detect deception.     

Cold‐blooded lie catchers? An investigation of psychopathy,emotional processing,and deception detection

Purpose. The process of catching liars is challenging, though evidence suggests that deception detection abilities are influenced by the characteristics of the judge. This study examined individual differences in emotional processing and levels of psychopathic traits on the ability to judge the veracity of written narratives varying in emotional valence. Methods. Undergraduate participants (N= 251) judged the veracity of 12 written narratives (truthful/deceptive) across three emotional categories: positive, negative, and neutral events. Levels of psychopathy were assessed to investigate its relation to accuracy and cue use. Results. Overall accuracy was close to chance, although participants were more accurate in determining the veracity of truthful relative to deceptive narratives. Accuracy was impaired for emotional (positive and negative) relative to neutral narratives. Psychopathy was not associated with levels of overall accuracy, but related to discriminative ability, and differential use of cues in decision making. Reported cue use also differed across emotional narrative conditions. Conclusions. We speculated that an emotive truth bias may have detracted judges from attending to valid cues that are indicative of the deceptive nature of stimuli because they were distracted by the emotional content of the report. Implications for deception detection in forensic settings are discussed.     

Applying the Verifiability Approach in an international airport setting

In the current study, we tested the utility of applying the Verifiability Approach (VA) within an international airport setting. The VA works on the notion that truth tellers provide more verifiable details than liars and has shown to be successful within other empirical deception detection scenarios. Three hundred and ninety-nine airside participants (those originating from Europe, Asia and African) were asked questions regarding their travel plans. We asked participants to either lie (n?=?195) or tell the truth (n?=?204) about their planned activities. The critical question required participants to provide information that would convince the investigator that they were telling the truth. We then transcribed and coded their responses for verifiable details; that is, details that could potentially be checked by an investigator. Overall, truth tellers provided significantly more verifiable details than liars. Furthermore, when taking their geographical origin into account, there was no interaction effect between veracity and region. Additionally, truth tellers provided a higher verifiable/total detail ratio than liars, which again showed no interaction effect between veracity and region. These findings support the suitability of the VA as a cross-cultural veracity tool and implications for its use as an additional security aid are discussed.     

Guilty and innocent suspects’ strategies during police interrogations

Abstract

Deception detection has largely failed to investigate guilty and innocent suspects’ strategies. In this study, mock suspects (n=82) were interrogated by police trainees (n=82) who either were or were not trained in the technique to strategically use the evidence (the SUE technique). Analyses revealed that guilty suspects to a higher degree than innocent suspects applied strategies in order to appear truthful. Guilty suspects reported diverse strategies, while innocent suspects reported the strategy to tell the truth like it had happened, indicating a belief in the visibility of innocence. The realism in the suspects’ expectation about how their veracity was judged was largely dependent on the way in which they had been interrogated. The truth-telling suspects who were interrogated according to the SUE technique were optimistic about being judged as truthful; this optimism was warranted as the vast majority of them were classified as truthful. The SUE technique seems to help (a) spotting guilty suspects without them being aware of it and (b) spotting innocent suspects, and they become aware of it. That innocent (but not guilty) suspects can read how the interrogator views them is advantageous for the investigative process.     

Using sketch drawing to induce inconsistency in liars

Purpose. Consistency as a cue to detecting deception was tested in two experiments using sketch drawing and verbal reports in repeated interviews. Liars were expected to be less consistent than truth‐tellers. Methods. In Expt 1, 80 undergraduate students reported truthfully or deceptively about an alleged lunch date – they sketched the layout of the restaurant and then answered spatial questions about objects in the restaurant. Ratings were given for the consistency between sketches and verbal reports. In Expt 2, 34 undergraduate students reported truthfully or deceptively about completing a series of unrelated tasks – they answered spatial questions about objects in a room and then sketched the layout of the room. Proportions were calculated for the consistency between verbal reports and sketches. Results. Expt 1. Liars were rated as less consistent than truth‐tellers. Up to 80% of truth‐tellers and 70% of liars could be correctly classified. Expt 2. Liars were less consistent than truth‐tellers on consistency proportions. Up to 100% of truth‐tellers and 77% of liars could be correctly classified. Conclusions. Using sketches to induce inconsistency may be a reliable, resource efficient way to help investigators detect deception.     

Detecting deception in suspects: verbal cues as a function of interview strategy

Research on deception has consistently shown that people are poor at detecting deception, partly due to lack of consistent cues to deception. This research focuses on eliciting verbal cues to deception when questioning suspects who deny crime and how such cues differ due to type of questioning. An experiment examined verbal differences between innocent and guilty mock suspects (N=96) as a function of veracity and interview style (Free recall, Probes, or Free recall plus Probes). Guilty (vs innocent) suspects omitted more crime-relevant information and their statements were more likely to contradict the evidence, showing that statement–evidence inconsistency was a cue to deception. This cue to deception was more pronounced when the interview contained probes. Lie-catchers (N=192) obtained an accuracy rate higher than chance (61.5%) for detecting deceptive denials. Implications for further research on verbal cues to deception are discussed.     

Clusters of Nonverbal Behaviors Differ According to Type of Question and Veracity in Investigative Interviews in a Mock Crime Context

Evaluating truthfulness and detecting deception is a capstone skill of criminal justice professionals, and researchers have long examined nonverbal cues to aid in such determinations. This paper examines the notion that testing clusters of nonverbal behaviors is a more fruitful way of making such determinations than single, specific behaviors. Participants from four ethnic groups participated in a mock crime and either told the truth or lied in an investigative interview. Fourteen nonverbal behaviors of the interviewees were coded from the interviews; differences in the behaviors were tested according to type of question and veracity condition. Different types of questions produced different nonverbal reactions. Clusters of nonverbal behaviors differentiated truth tellers from liars, and the specific clusters were moderated by question. Accuracy rates ranged from 62.6 to 72.5% and were above deception detection accuracy rates for humans and random data. These findings have implications for practitioners as well as future research and theory.     

Detecting Deception Via Strategic Disclosure of Evidence

Deception detection research has largely neglected an important aspect of many investigations, namely that there often exists evidence against a suspect. This study examined the potentials of timing of evidence disclosure as a deception detection tool. The main prediction was that observers (N = 116) would obtain higher accuracy rates if the evidence against the suspects (N = 58) was presented in a late rather than early stage of the interrogation. This prediction was based on the idea that late evidence disclosure would trigger lack of consistencies between the liars’ stories and the evidence; this could be used as a cue to deception. The main prediction received support. Late disclosure observers obtained an overall accuracy of 61.7%, compared to 42.9% of Early disclosure observers. Deceptive statements were identified with high accuracy (67.6%) in Late disclosure, indicating that the technique in this form is beneficial mainly for pinpointing lies.     

Observers’ Real-Time Sensitivity to Deception in Naturalistic Interviews

This study tested the ability of experienced interviewers and novice observers to detect deception while watching mock interviews featuring experimental or control questioning methods and different detainee languages. The protocol featured a complex, realistic critical event and naturalistic interviews in which mock detainees could report unconstrained. Experimenters recorded these interviews and presented them to observers who judged veracity in real time. In general, experienced interviewers were no more sensitive to deception than were novices and both groups set conservative response criteria. Observers were more sensitive to deception when viewing control versus experimental questioning methods. Observers were more sensitive to deception when viewing Arabic speakers interviewed through an interpreter. Results imply that not all trained interviewers exhibit a lie bias; additional research should examine how best to transition lab-tested interview methods into the field, and language and interpreter factors may impact the ability to assess veracity in multiple ways.     

The Accuracy of Auditors' and Layered Voice Analysis (LVA) Operators' Judgments of Truth and Deception During Police Questioning*

The purpose of this study was to determine if auditors could identify truthful and deceptive persons in a sample (n = 74) of audio recordings used to assess the effectiveness of layered voice analysis (LVA). The LVA employs an automated algorithm to detect deception, but it was not effective here. There were 31 truthful and 43 deceptive persons in the sample and two LVA operators averaged 48% correct decisions on truth‐tellers and 25% on deceivers. Subsequent to the LVA analysis the recordings were audited by three interviewers, each independently rendering a decision of truthful or deceptive and indicating their confidence. Auditors' judgments averaged 68% correct decisions on truth‐tellers and 71% on deceivers. Auditors' detection rates, generally, exceeded chance and there was significantly (p < 0.05) greater confidence on correct than incorrect judgments of deceivers but not on truth‐tellers. These results suggest that the success reported for LVA analysis may be due to operator's judgment.     

Criteria-Based Content Analysis: An empirical test of its underlying processes

Abstract

Criteria-Based Content Analysis (CBCA) is a tool to assess the veracity of written statements, and is used as evidence in criminal courts in several countries in the world. CBCA scores are expected to be higher for truth tellers than for liars. The underlying assumption of CBCA is that (i) lying is cognitively more difficult than truth telling, and (ii) that liars are more concerned with the impression they make on others than truth tellers. However, these assumptions have not been tested to date. In the present experiment 80 participants (undergraduate students) lied or told the truth about an event. Afterwards, they completed a questionnaire measuring “cognitive load” and “tendency to control speech”. The interviews were transcribed and coded by trained CBCA raters. In agreement with CBCA assumptions, (i) truth tellers obtained higher scores than liars, (ii) liars experienced more cognitive load than truth tellers, and (iii) liars tried harder to control their speech. However, cognitive load and speech control were not correlated with CBCA scores in the predicted way.