SCAN is largely driven by 12 criteria: results from sexual abuse statements

Scientific Content Analysis (SCAN) is increasingly used by investigative authorities to evaluate the credibility of statements made by witnesses and suspects. SCAN, however, lacks a well-defined list of criteria, and does not involve a standardised scoring system. In the current study, we investigated which SCAN criteria are represented in actual statements. To this end, we analysed 82 sexual abuse cases of the Dutch police in which SCAN had been applied. Two independent coders scored the presence of various SCAN criteria in the: (1) written statements from victims, suspects, and witnesses; and also looked at the (2) recommendations for follow-up investigations that were derived from SCAN. Results showed that SCAN is primarily driven by 12 criteria. Results also indicated a low inter-rater agreement for most SCAN criteria, suggesting SCAN is insufficiently developed as a forensic tool. Still, the 12 criteria can be used as a starting point for future research on their psychometric properties.     

Does the truth come out in the writing? Scan as a lie detection tool

We tested the accuracy of Scientific Content Analysis (SCAN), a verbal lie detection tool that is used world-wide by federal law enforcement and military agencies. Sixty-one participants were requested to write down the truth, an outright lie or a concealment lie about activities they had just completed. The statements were coded with SCAN and with another verbal lie detection tool, Reality Monitoring (RM). RM discriminated significantly between truth tellers and outright liars and between truth tellers and concealment liars, whereas SCAN did not discriminate between truth tellers and either kind of liar. Implications of the findings for the suitability of SCAN as a lie detection tool are discussed.     

To Behave Like a Liar: Nonverbal Cues to Deception in an Asian Sample

The detection of deception is an essential yet challenging component of investigative interviewing. Behavioural cues to deception in particular, have long been used in investigative interviewing contexts to determine decisions of suspect veracity and deceit. Nevertheless, deception research amongst non-American or European populations has yet to fully explore the effectiveness of such non-verbal observations. This study may be the first to examine truth-lie behaviours involving South-East Asian participants. In this study conducted in Singapore, 68 participants completed either a mock criminal task or a non-criminal task, before encountering an investigative interviewing scenario in which they had to lie or tell the truth to the interviewer. The results showed that liars displayed significantly more head movements and less hand/finger movements, as well as reported more feelings of guilt, than truth-tellers. Implications for investigator training and criminal investigative procedures are discussed.     

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.     

A non-standard method for estimating accuracy of lie detection techniques demonstrated on a self-validating set of field polygraph examinations

Abstract

A unique method for estimating field accuracy of the Comparison Question Test (CQT) – a polygraph technique – is presented, based on a combined probabilistic and algebraic model. It is built on paired examinations in criminal cases in which two opposing versions per case have been subjected to polygraph tests. The developed model is ground-truth free, thus there was no need to rely on external criteria of deception (e.g., confessions or physical evidence) in estimating the accuracy of the CQT. Results indicate an accuracy rate of 0.94 in detecting guilty examinees (Sensitivity) with a 0.06 False Negative rate and an accuracy rate of 0.835 (Specificity) with False Positive of 0.165 for the innocents. These figures excluded 20% of the cases that were ruled inconclusive. When no inconclusive calls were allowed, the accuracy rate dropped down to 0.8 with 0.2 error rates for both the guilty and the innocent examinees. The importance of this research stems from its being a field study that due to the unique methodology was not subjected to weaknesses usually found in polygraph field validity studies. This method is applicable to other techniques of deception detection and with some necessary adaptations may be also to eyewitness situations.     

Psychopathy and deception detection using indirect measures

Purpose. The goal of the current study was to examine psychopathy and indirect measures of deception detection. Methods. Undergraduate students (N=444) viewed video clips of adult male offenders telling true and false stories about crimes. For each story, participants rated indirect measures of deception (thinking hard, nervousness, emotional arousal, and attempting to control behaviour) and credibility. Participants also chose the story they believed to be true and rated the confidence in their decision. Offenders were rated on the psychopathy checklist – revised. Results. Consistent with past research, deception detection accuracy was at chance level and unrelated to confidence. Ratings on indirect measures by undergraduates did not distinguish true and false statements in offenders. Psychopathic offenders were less successful at deception than non‐psychopathic offenders. Psychopathic traits were associated with lower perceived credibility during deception and ratings of thinking harder while lying. Conclusions. The results suggest that indirect measures of deception detection may be less useful in offender samples. Further, the findings are consistent with the general inability of psychopathic offenders to demonstrate superior deception skills in empirical studies. Indirect measures of deception uniquely related to psychopathic traits offer new insight into the relationship between psychopathy and deception.     

Deception among pairs: “Let's say we had lunch and hope they will swallow it!”

Deception research has neglected the fact that legal-workers often have to try to detect deceit on the basis of statements derived from pairs of suspects, each having been interrogated repeatedly. To remedy this shortcoming we conducted a study where each member of 10 truth-telling pairs and 10 lying pairs was interrogated twice about an alibi. One hundred and twenty undergraduate students were enrolled as lie-catchers. The main findings were that (a) overall deception detection accuracy was modest; (b) lie-catchers given access to a large number of statements did not outperform lie-catchers given access to a lesser number of statements; (c) when asked to justify their veracity assessments the most frequently reported cue was ‘consistency within pairs of suspects’; (d) all cues to deception were of low diagnostic value. Psycho-legal aspects of integrating sequential information in deception detection contexts are discussed.     

In the eye of the beholder? An examination of the inter-rater reliability of the LSI-R and YLS/CMI in a correctional agency

PurposeTo examine the inter-rater reliability of two risk assessment tools: The Level of Service Inventory-Revised (LSI-R) and the Youth Level of Service/Case Management Inventory (YLS/CMI).MethodsTwo identical experiments are reported. For both studies, a random sample of 10 offenders were interviewed and videotaped with each tool (totaling 20 offenders). The tapes were then shown to a random selection of 20 raters (for a total of 40 raters) employed at a state agency. The fully-crossed design allowed each of the raters to rate the each of the cases, resulting in 200 total risk score observations for each tool. Inter-rater reliability analyses were then conducted.ResultsThe LSI-R demonstrated adequate to fair reliability, with certain domains showing lower reliability. Overall, the LSI-R had an ICC of .65. The YLS/CMI demonstrated higher reliability (ICC of .78). In addition, for the LSI-R study, comparisons were made between staff raters who work in a facility versus those in the community (e.g., probation officers). For the YLS/CMI study, comparisons were made between incarcerated offenders versus probationers. Neither comparison yielded consistent differences.ConclusionsThe YLS/CMI is generally reliable. The LSI-R showed less reliability. However, each study showed certain domains with less than ideal reliability.     

Children recalling an event repeatedly: Effects on RM and CBCA scores

Purpose. The fact that abused children often talk about their experiences before entering the legal system is a neglected factor in terms of the validation of different reliability assessment techniques. Hence, the present study investigated the extent to which the scores of the reality monitoring technique (RM) and the criteria‐based content analysis technique (CBCA) were affected by the number of times children recalled an experienced or an imagined event. Method. Children (aged 12–13 years, N – 80) participated in an experiment where half the sample experienced a real event (an interaction with a stranger outside his car) and then recalled it either one or four times (over a period of 14 days), and the other half imagined the same event and thereafter recalled it either one or four times. The statements given at the final (or only) recall session were analysed with both CBCA and RM. Results. The results revealed that, on a multivariate level, both the CBCA and RM sets of criteria discriminated between truthful and fabricated statements. The total RM score (but not the total CBCA score) discriminated reliably between truthful and fabricated statements. Furthermore, RM (but not CBCA) were sensitive to the number of times the experienced or imagined event was recalled: increased presence of criteria after repeated recall. Conclusions. The results were rather promising for the RM and less so for the CBCA. Furthermore, we found that the number of recalls moderated the effectiveness of the techniques. Hence, when assessing the reliability of a child's memory, it is crucial to learn about the history of the first documented statement.     

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/.     

A Sequence Analysis of Nonverbal Behaviour and Deception

The ability to correctly interpret nonverbal communication (NVC) is an important ability in everyday interactions, which may use NVC techniques to identify the concealment of information. In the present study, a novel approach was used to understand NVC. Behaviour sequence analysis identified specific sequences of behaviours that indicate psychological distress caused by deception. The study involved the analysis of 55 videos of real criminals and high-power individuals that were filmed fabricating statements, which were later exposed as being untruthful at the time of being filmed. In addition, 53 clips of criminals making truthful statements were also analysed as a contrast group. Results indicated clear differences between honest and deceptive responses, such as furrowing of eyebrows in the deceptive sequences occurring more often than honest statements. In addition, sequences of behaviours were shown in the present data set, which could indicate a new method for analysing NVC and detecting psychological distress caused by deception. The possible implications and applications for police and forensic investigation are also outlined.     

Reliability of a two-dimensional sock-clad footprint linear measurement method

A two-dimensional linear measurement approach for footprints, herein referred to as the “Reel Method,” has been shown to be valid and reliable when used on bare footprints, however, few measurement approaches have been examined on sock-clad footprints. The present investigation examines the validity and reliability of the Reel Method as a two-dimensional linear measurement approach for use on sock-clad footprints.A walking, mid-gait footprint was collected from 30 volunteer participants using the Identicator Inkless Shoe Print Model LE 25P system. The width of the ball of the foot, calcaneal width, and distance from the most posterior aspect of the heel to the most distal aspect of the first toe were each measured and compared between and within three raters. The statistical analysis demonstrated high reliability of the Reel Method among these three raters. The data were found to be normally distributed, and measurements were consistent between and within raters. 95% Intraclass Correlation coefficients, 95% Bland-Altman Limits of Agreement and 95% Standard Error of Measurement determined high statistical agreement between and within raters, demonstrating that the Reel Method is reliable and thus valid for the linear measurement of sock-clad footprints.     

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.     

P300用于31例刑事在押人员的检测准确性研究

目的验证事件相关电位测谎方法对刑事在押人员进行检测时的准确性,从而推动该项测谎技术从实验室走向实践。方法以31例涉案的犯罪嫌疑人为研究对象,以P300为评价指标进行事件相关电位测谎。结果事件相关电位测谎方法的准确判别率为96.8%,而测谎结论的准确率为80.6%。结论事件相关电位测谎结果没有假阳性,有利于认定犯罪事实,可以用于刑事案件测谎当中。     

Will the law come running? The potential role of "brain fingerprinting" in crime investigation and adjudication in Australia

A major feature of the Australian criminal justice system is that jurors assess witness credibility and are the ultimate finders of fact. Recognising the occasional fallibility of humans in detecting truth and deception, the jury's function may be assisted by highly regulated expert evidence about a variety of scientific techniques. A recent scientific development has been the invention of "brain fingerprinting" (BF) by Dr Larry Farwell in the United States. Brain fingerprinting measures brainwave functioning to detect awareness of crime-relevant information in order to distinguish between guilty and innocent suspects. This article considers whether BF could be used for crime investigation and adjudication in Australia. By examining the rules of expert evidence and the principles relating to "novel scientific evidence", the admissibility of BF in the various Australian jurisdictions is evaluated. The utility of BF in criminal investigations and counter-terrorism initiatives is also canvassed. The authors conclude that, at the present time, it is unlikely that expert testimony on BF will be admitted in Australian criminal trials. However, the technique potentially offers other benefits to the criminal justice system, thereby warranting its consideration as a "criminal and investigative tool of the future".     

Is That What I Said?: Witnesses' Responses to Interviewer Modifications

Modifications occur when interviewers contradict statements made by witnesses or imply that witnesses provided information that they (interviewers) did not provide. Because of their suggestive nature, modifications threaten the reliability of investigative interviews. This study investigated developmental differences in witnesses' responses to modifications during interviews as well as in inclusion of modified misinformation in subsequent answers. Preschool, elementary school, and college students were interviewed about a video presentation. In the experimental conditions, the interviewer contradicted information about the video provided by the participants. Participants then answered two sets of follow-up questions: one immediately following the interview and another 6–8 days later. Results indicated that participants were more likely to ignore modifications than to correct or agree with them. Adult participants were most likely to disagree with modifications. Preschoolers were most likely to incorporate modified misinformation into subsequent answers. Implications of these findings for investigative interviews are discussed.