The Forensic Confirmation Bias: A Comparison Between Experts and Novices

A large body of research has described the influence of context information on forensic decision‐making. In this study, we examined the effect of context information on the search for and selection of traces by students (N = 36) and crime scene investigators (N = 58). Participants investigated an ambiguous mock crime scene and received prior information indicating suicide, a violent death or no information. Participants described their impression of the scene and wrote down which traces they wanted to secure. Results showed that context information impacted first impression of the scene and crime scene behavior, namely number of traces secured. Participants in the murder condition secured most traces. Furthermore, the students secured more crime‐related traces. Students were more confident in their first impression. This study does not indicate that experts outperform novices. We therefore argue for proper training on cognitive processes as an integral part of all forensic education.     

Identifying and measuring juror pre-trial bias for forensic evidence: development and validation of the Forensic Evidence Evaluation Bias Scale

Abstract

Previous research has provided support for the impact of juror pre-trial bias on judicial decision making, particularly in cases where the evidence presented at trial is of weak or ambiguous probative value. In an effort to identify whether a pre-trial bias for forensic evidence exists, the Forensic Evidence Evaluation Bias Scale (FEEBS) was developed and tested. The results of a principal components analysis suggested that two distinct constructs were being measured, corresponding to a pro-prosecution and pro-defence bias toward forensic evidence. In a second validation study, scores on these two subscales were compared with other existing juror bias measures (Juror Bias Scale and Belief in a Just World) and in a mock juror decision making task only the pro-prosecution subscale of the FEEBS predicted the perceived strength of forensic evidence. A partial mediation model is presented which explains the relationship between this bias and verdict preferences. The implications of this potential juror bias are discussed in the context of real juries, the CSI Effect (which refers to anecdotal claims that jurors are biased by the popularity of fictional representations of forensic science on television) and peremptory challenges, as well as future research directions.     

Diagnosing Crime and Diagnosing Disease: Bias Reduction Strategies in the Forensic and Clinical Sciences

Cognitive effort is an essential part of both forensic and clinical decision‐making. Errors occur in both fields because the cognitive process is complex and prone to bias. We performed a selective review of full‐text English language literature on cognitive bias leading to diagnostic and forensic errors. Earlier work (1970–2000) concentrated on classifying and raising bias awareness. Recently (2000–2016), the emphasis has shifted toward strategies for “debiasing.” While the forensic sciences have focused on the control of misleading contextual cues, clinical debiasing efforts have relied on checklists and hypothetical scenarios. No single generally applicable and effective bias reduction strategy has emerged so far. Generalized attempts at bias elimination have not been particularly successful. It is time to shift focus to the study of errors within specific domains, and how to best communicate uncertainty in order to improve decision making on the part of both the expert and the trier‐of‐fact.     

A Perspective on Errors,Bias, and Interpretation in the Forensic Sciences and Direction for Continuing Advancement*

Abstract: The forensic sciences are under review more so than ever before. Such review is necessary and healthy and should be a continuous process. It identifies areas for improvement in quality practices and services. The issues surrounding error, i.e., measurement error, human error, contextual bias, and confirmatory bias, and interpretation are discussed. Infrastructure is already in place to support reliability. However, more definition and clarity of terms and interpretation would facilitate communication and understanding. Material improvement across the disciplines should be sought through national programs in education and training, focused on science, the scientific method, statistics, and ethics. To provide direction for advancing the forensic sciences a list of recommendations ranging from further documentation to new research and validation to education and to accreditation is provided for consideration. The list is a starting point for discussion that could foster further thought and input in developing an overarching strategic plan for enhancing the forensic sciences.     

Racial Bias in Mock Juror Decision-Making: A Meta-Analytic Review of Defendant Treatment

Common wisdom seems to suggest that racial bias, defined as disparate treatment of minority defendants, exists in jury decision-making, with Black defendants being treated more harshly by jurors than White defendants. The empirical research, however, is inconsistent—some studies show racial bias while others do not. Two previous meta-analyses have found conflicting results regarding the existence of racial bias in juror decision-making (Mazzella & Feingold, 1994, Journal of Applied Social Psychology, 24, 1315–1344; Sweeney & Haney, 1992, Behavioral Sciences and the Law, 10, 179–195). This research takes a meta-analytic approach to further investigate the inconsistencies within the empirical literature on racial bias in juror decision-making by defining racial bias as disparate treatment of racial out-groups (rather than focusing upon the minority group alone). Our results suggest that a small, yet significant, effect of racial bias in decision-making is present across studies, but that the effect becomes more pronounced when certain moderators are considered. The state of the research will be discussed in light of these findings.     

How Cross‐Examination on Subjectivity and Bias Affects Jurors’ Evaluations of Forensic Science Evidence

Contextual bias has been widely discussed as a possible problem in forensic science. The trial simulation experiment reported here examined reactions of jurors at a county courthouse to cross‐examination and arguments about contextual bias in a hypothetical case. We varied whether the key prosecution witness (a forensic odontologist) was cross‐examined about the subjectivity of his interpretations and about his exposure to potentially biasing task‐irrelevant information. Jurors found the expert less credible and were less likely to convict when the expert admitted that his interpretation rested on subjective judgment, and when he admitted having been exposed to potentially biasing task‐irrelevant contextual information (relative to when these issues were not raised by the lawyers). The findings suggest, however, that forensic scientists can immunize themselves against such challenges and maximize the weight jurors give their evidence by adopting context management procedures that blind them to task‐irrelevant information.     

The Power of Contextual Effects in Forensic Anthropology: A Study of Biasability in the Visual Interpretations of Trauma Analysis on Skeletal Remains

The potential for contextual information to bias assessments in the forensic sciences has been demonstrated, in several forensic disiplines. In this paper, biasability potential within forensic anthropology was examined by analyzing the effects of external manipulations on judgments and decision‐making in visual trauma assessment. Three separate websites were created containing fourteen identical images. Participants were randomly assigned to one website. Each website provided different contextual information, to assess variation of interpretation of the same images between contexts. The results indicated a higher scoring of trauma identification responses for the Mass grave context. Furthermore, a significant biasing effect was detected in the interpretation of four images. Less experienced participants were more likely to indicate presence of trauma. This research demonstrates bias impact in forensic anthropological trauma assessments and highlights the importance of recognizing and limiting cognitive vulnerabilities that forensic anthropologists might bring to the analysis.     

Context Effects in Forensic Entomology and Use of Sequential Unmasking in Casework

Context effects are pervasive in forensic science, and are being recognized by a growing number of disciplines as a threat to objectivity. Cognitive processes can be affected by extraneous context information, and many proactive scientists are therefore introducing context‐minimizing systems into their laboratories. Forensic entomologists are also subject to context effects, both in the processes they undertake (e.g., evidence collection) and decisions they make (e.g., whether an invertebrate taxon is found in a certain geographic area). We stratify the risk of bias into low, medium, and high for the decisions and processes undertaken by forensic entomologists, and propose that knowledge of the time the deceased was last seen alive is the most potentially biasing piece of information for forensic entomologists. Sequential unmasking is identified as the best system for minimizing context information, illustrated with the results of a casework trial (n = 19) using this approach in Victoria, Australia.     

ISO Standards Addressing Issues of Bias and Impartiality in Forensic Work

The ISO/IEC 17020 and 17025 standards both include requirements for impartiality and the freedom from bias. Meeting these requirements for implicit cognitive bias is not a simple matter. In this article, we address these international standards, specifically focusing on evaluating and mitigating the risk to impartiality, and quality assurance checks, so as to meet accreditation program requirements. We cover their meaning to management as well as to practitioners, addressing how these issues of impartiality and bias relate to forensic work, and how one can effectively evaluate and mitigate those risks. We then elaborate on specific quality assurance policies and checks and identify when corrective action may be appropriate. These measures will not only serve to meet ISO/IEC 17020 and 17025 requirements, but also enhance forensic work and decision-making.     

Implications of Pseudologia Fantastica in Criminal Forensic Evaluations: A Review and Case Report

Pseudologia fantastica, a psychological phenomenon that has been described in the literature for at least a century, is an understudied and poorly understood entity. Sometimes referred to as pathological lying, pseudologia fantastica involves disproportionate fabrication that may be present for many years or a lifetime. In a forensic context, it can significantly complicate the evaluation of capacity to stand trial and, in certain jurisdictions, criminal responsibility. We review the current literature regarding pseudologia fantastica and present a case to highlight the clinical and forensic challenges it may create. We specifically discuss the complications that pseudologia fantastica may have on the assessment of a defendant's rational ability to consult with an attorney, a required element of capacity to stand trial. In addition, we discuss the implications of pseudologia fantastica in the evaluation of criminal responsibility.     

Creating a State‐Academic Partnership to Advance a Forensic Teaching Service: Benefits and Barriers

In Washington State, like many states, there is a shortage of forensically trained mental health clinicians to work with criminal justice‐involved individuals. At the direction of the state legislature, a collaborative project was undertaken by the University of Washington, the state Department of Social and Health Services, and a state psychiatric hospital to develop a proposal for a jointly sponsored forensic teaching service. The authors reviewed the literature, surveyed and interviewed forensic psychiatry and psychology training directors, and conducted site visits of selected training programs that offer multidisciplinary training or have affiliations with state hospitals. The authors conducted focus groups of additional stakeholders, including clinicians and patients in forensic settings, to better understand the needs in Washington. The authors report on several common benefits and barriers to establishing forensic teaching services. Other states and forensic programs may find this article useful in identifying common considerations for forensic mental health teaching services.     

The Value of Crime Scene and Site Visitation by Forensic Psychologists and Psychiatrists

Site visits and crime scene visitation by forensic psychologists and psychiatrists may enhance the accuracy and credibility of their forensic work in criminal, civil, and other important contexts. This ethically sound technique of after‐the‐fact data collection and verification offers numerous potential benefits to the forensic mental health professional: clarifying the subject's actions, assessing the reliability of witness reports, identifying contextual determinants of behavior, and more fully illuminating subject motivation and decision‐making. Limitations and suggested guidelines for conducting site visits are offered. Guidelines include preplanning, arranging for an informed guide to accompany and narrate the visit, and conducting the site visit prior to forensic examinations.     

The Griffiths Question Map: A Forensic Tool For Expert Witnesses’ Assessments of Witnesses and Victims’ Statements

Expert witnesses are sometimes asked to assess the reliability of young witnesses and victims’ statements because of their high susceptibility to memory biases. This technical note aims to highlight the relevance of the Griffiths Question Map (GQM) as a professional forensic tool to improve expert witnesses’ assessments of young witnesses and victims’ testimonies. To do so, this innovative question type assessment grid was used to proceed to an in‐depth analysis of the interview of an alleged 13‐year‐old victim of a sexual assault and two rapes. Overall, the GQM stressed how the interview was mainly conducted in an inappropriate manner. The results are examined with regard to scientific knowledge on young witnesses and victims’ memory. Finally, it is argued that expert witnesses in inquisitorial systems might use the GQM while encountering difficulties to fulfill the legal standards for expert evidence in adversarial systems because of the lack of studies regarding its reliability.     

Organizational and Human Factors Affecting Forensic Decision-Making: Workplace Stress and Feedback

Although forensic examiners operate in a stressful environment, there is a lack of understanding about workplace stress and feedback. These organizational and human factors can potentially impact forensic science judgments. In this study, 150 practicing forensic examiners from one laboratory were surveyed about their experiences of workplace stress, and the explicit and implicit feedback they receive. Forensic examiners reported that their high stress levels originated more from workplace-related factors (management and/or supervision, backlogs, and the pressure to do many cases) than from personal related factors (family, medical, and/or financial). The findings showed that a few (8%) of the forensic examiners sometimes felt strong implicit feedback about what conclusions were expected from them and that some (14%) also strongly felt that they were more appreciated when they helped to solve a case (e.g., by reaching a “match” as opposed to an “inconclusive” conclusion). Differences were found when comparing workplace stress and feedback levels across three core forensic science fields (forensic biology, chemistry, and latent prints) and across career stages (early, mid, and late). Gaining insights into the stress factors within a workplace and explicit and implicit feedback has implications for developing policies to improve the well-being, motivation, and performance of forensic examiners.     

Validation of the factor structure and predictive validity of the Forensic Evidence Evaluation Bias Scale for robbery and sexual assault trial scenarios

In order to investigate the role of pre-trial attitudes about forensic science in juror decision-making, a previous study demonstrated the predictive validity of the Forensic Evidence Evaluation Bias Scale (FEEBS), using a murder trial scenario, which featured ambiguous prosecution DNA evidence. The current study validates the FEEBS using two new crime types and the conditions include a manipulation of the presence of DNA evidence in the trial scenario. The FEEBS successfully predicted mock jurors' perceptions of the probative value of DNA evidence for both robbery and sexual assault trials. The two subscales of the FEEBS were demonstrated to have different predictive ability depending on the presence or absence of DNA evidence. A confirmatory factor analytic technique was used to validate the underlying two-factor structure of the FEEBS, as previously proposed. These results are discussed with reference to the CSI Effect literature, and the potential for improvement to less empirically supported voir dire questioning techniques.     

Testing for Potential Contextual Bias Effects During the Verification Stage of the ACE‐V Methodology when Conducting Fingerprint Comparisons*

Abstract: This study was conducted to assess if fingerprint specialists could be influenced by extraneous contextual information during a verification process. Participants were separated into three groups: a control group (no contextual information was given), a low bias group (minimal contextual information was given in the form of a report prompting conclusions), and a high bias group (an internationally recognized fingerprint expert provided conclusions and case information to deceive this group into believing that it was his case and conclusions). A similar experiment was later conducted with laypersons. The results showed that fingerprint experts were influenced by contextual information during fingerprint comparisons, but not towards making errors. Instead, fingerprint experts under the biasing conditions provided significantly fewer definitive and erroneous conclusions than the control group. In contrast, the novice participants were more influenced by the bias conditions and did tend to make incorrect judgments, especially when prompted towards an incorrect response by the bias prompt.     

Forensic Gait Analysis and Recognition: Standards of Evidence Admissibility

Gait is one biological characteristic which has attracted strong research interest due to its potential use in human identification. Although almost two decades have passed since a forensic gait expert has testified to the identity of a perpetrator in court, the methods remain insufficiently robust, considering the recent paradigm shift witnessed in the forensic science community regarding quality of evidence. In contrast, technological advancements have taken the lead, and research into automated gait recognition has greatly surpassed forensic gait analysis in terms of the size of acquired datasets and demographic variability of participants, tested variables, and statistical evaluation of results. Despite these advantages, gait recognition presents with different problems which are yet to be resolved. Therefore, courts should treat gait evidence with caution, as they should any other form of evidence originating from disciplines without fully established codes of practice, error rates, and demonstrable applications in forensic scenarios.     

How to Improve Forensic Science

Some institutional structures for inquiry produce better approximations to truth than others. The current institutional structure of police forensics gives each lab a monopoly in the analysis of the police evidence it receives. Forensic workers have inadequate incentives to produce reliable analyses of police evidence. Competition would create such incentives. I outline a system of “competitive self regulation” for police forensics.Each jurisdiction would have several competing forensic labs. Evidence would be divided and sent to one, two, or three separate labs.Chance would determine which labs and how many would receive evidence to analyze.Competitive selfregulation improves forensics by creating incentives for error detection and reducing incentives to produce biased analyses. JEL Classification: K14, K42, H11     

Radiocarbon Analysis of Human Remains: A Review of Forensic Applications

Radiocarbon analysis of organic materials, with the comparison of values with those of the post‐1950 modern bomb curve, has proven useful in forensic science to help evaluate the antiquity of evidence. Applications are particularly helpful in the study of human remains, especially with those displaying advanced decomposition of soft tissues. Radiocarbon analysis can reveal if the remains relate to the modern, post‐1950 era and if so, also provide information needed to evaluate the death and birth date. Sample selection and interpretation of results must be guided by knowledge of the formation and remodeling of different human tissues, as well as contextual information and the approximate age at death of the individual represented. Dental enamel does not remodel and thus captures dietary radiocarbon values at the time of juvenile formation. Most other human tissues do remodel but at differing rates and therefore collectively offer key information relative to the estimation of the death date.