The effects of cognitive bias, examiner expertise, and stimulus material on forensic evidence analysis.

Forensic examiners have come under scrutiny due to high-profile exonerations, highlighting the consequences that contextual bias can have on investigations. Researchers have proposed solutions to reduce the effects of bias including blind testing and redacting task-irrelevant information. Practitioners have concerns over the limitations of some of this research that uses untrained students to examine complex pieces of forensic evidence (e.g., fingerprints) (1; but see 2 for studies including trained experts and/or actual casework). This study sought to (a) examine the effect of contextual bias on examiners' evaluation of forensic evidence by varying the amount of pre-comparison information available to participants, (b) compare student and expert examiners' performance and their vulnerability to contextual bias, and (c) examine the effects of contextual bias on examiners' evaluation of different types of forensic evidence. Expert fingerprint examiners and student participants were presented with varying amounts of pre-comparison case information and compared matching and non-matching fingerprint and footwear impression evidence. Results suggest no effects of blinding examiners from case information or redacting task-irrelevant information. As expected, expert fingerprint examiners were more likely to correctly identify matching fingerprints and correctly exclude non-matching fingerprints than students. However, expert fingerprint examiners were no better than student participants at comparing footwear impression evidence. These findings suggest that sample, stimulus selection, and discipline-specific training matter when investigating bias in forensic decision making. These findings suggest caution when using forensic stimuli with student samples to investigate forensic decision-making and highlight the need for more research on redaction procedures.

Police-suspect interactions and confession rates are affected by suspects' alcohol and drug use status in low-stakes crime interrogations.

Background: Low-stakes crimes related to alcohol and/or drugs are common around the world, but research is lacking on police-suspect interactions of such crimes. A large proportion of these suspects are intoxicated during interrogations, and many may have substance use disorder, making them potentially vulnerable to interrogative pressure. Methods: To address this lack of knowledge, the taxonomy of interrogation methods framework (i.e., 60+ interrogation techniques classified into five domains) and a common classification of question types (appropriate vs. inappropriate) were applied in the coding of written police interrogations. Two archival studies, one pilot (Study 1, N = 39) and one main study (Study 2, N = 97) analyzed police interrogations with suspects of alcohol- and drug-related crimes in Sweden. Results: For both Study 1 and 2, suspects showed signs of alcohol and/or drug intoxication, hangover or withdrawal in more than 50% of all interrogations. In Study 2, additional coding indicated that suspects displayed signs of substance use disorder in 57% of the interrogations. The main results from both studies revealed a large number of direct questions asked by the police across all interrogations, and relatively little use of the strategic interrogation techniques from the taxonomy of interrogation methods framework. In fact, when it came to interrogation techniques, law enforcement used more confrontational techniques in their interactions with intoxicated suspects compared to sober suspects. Furthermore, suspects displaying signs of substance use disorder were significantly more cooperative and prone to confess than suspects without indicators of substance use disorder. Conclusion: As the first novel study on low-stakes crime interrogations related to alcohol and/or drugs, the present study provides useful information about current Swedish interrogation practices and areas for improvement. The study results indicate that suspects displaying signs of intoxication or substance use disorder may be more vulnerable during police interrogations. This may in turn have the potential to inform the development of new interrogation policies. Due to the novelty of this research, more studies are needed, both on a national and international level, to examine interrogations in low-stakes crimes further.

The detrimental impact of alcohol intoxication on facets of Miranda comprehension.

OBJECTIVE: Law enforcement officers often encounter alcohol-intoxicated suspects, suggesting that many suspects are presented with the challenge of grasping the meaning and significance of their Miranda rights while intoxicated. Such comprehension is crucial, given that Miranda is intended to minimize the likelihood of coercive interrogations resulting in self-incrimination and protect suspects' constitutional rights. Yet, the effects of alcohol on individuals' ability to understand and appreciate their Miranda rights remain unknown-a gap that the present study sought to address. HYPOTHESES: Informed by alcohol myopia theory (AMT), we predicted that intoxicated individuals would demonstrate impaired Miranda comprehension compared to sober individuals and those who believed they were intoxicated (but were in fact not; i.e., placebo participants). METHOD: After health screenings, participants completed the Wechsler Abbreviated Scale of Intelligence-Second Edition verbal subtests, rendering a Verbal Comprehension Index (VCI) score. We randomly assigned participants to consume alcohol (n = 51; mean breath alcohol concentration [BrAC] = 0.07%), a placebo condition (n = 44; BrAC = 0.00%), or a sober control condition (n = 41; BrAC = 0.00%). All participants (N = 136) completed the Miranda Rights Comprehension Instruments (MRCI), which measured participants' understanding of the Miranda warnings, recognition of the warnings, appreciation of their rights in interrogation and court settings, and understanding of Miranda-related vocabulary. RESULTS: We found a significant effect of intoxication condition on participants' understanding of Miranda warnings (η²p = .14) and Miranda-related vocabulary (η²p = .05) when controlling for VCI scores. Specifically, intoxicated participants received lower scores for understanding of warnings compared to sober and placebo participants, and lower scores for understanding of Miranda vocabulary compared to sober participants. Alcohol did not significantly impact Miranda rights recognition or appreciation. CONCLUSIONS: Alcohol intoxication may detrimentally impact some facets of Miranda comprehension. Thus, it is important that law enforcement consider refraining from questioning intoxicated suspects. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Police Survey: Procedures and Prevalence of Intoxicated Witnesses and Victims in Sweden / Encuesta policial: procedimientos y prevalencia en testigos y víctimas intoxicados en Suecia

AbstractBackground:Despite the common occurrence of alcohol-related crimes, the Swedish police authority currently lacks national guidelines for dealing with intoxicated victims/witnesses.

Antecedentes: A pesar de que los delitos relacionados con el alcohol son bastante frecuentes, la policía sueca carece en la actualidad de directrices con las que hacer frente a los interrogatorios y entrevistas de víctimas y testigos intoxicados. Método: Esta encuesta trata de explorar los procedimientos de la policía ante personas intoxicadas y comparar los resultados con estadísticas internacionales. Con el fin de facilitar la comparación internacional la encuesta fue ajustada en contenidos a la investigación previa y adaptada al contexto sueco. Se envió una solicitud con un enlace a la encuesta a todas las regiones policiales de Suecia. Resultados: Ciento treinta y tres agentes de policía respondieron que era habitual interactuar con testigos/víctimas intoxicados. Algunos departamentos de policía disponían de directrices locales sobre cómo llevar a cabo entrevistas de investigación con personas intoxicadas pero dependía de cada agente formarse un juicio subjetivo sobre la interacción con estos testigos. Los datos evidenciaron que la alta prevalencia de testigos/víctimas intoxicadas en Suecia es similar a la de Australia, EE. UU. y Reino Unido. Parece que la policía sueca desconoce la investigación sobre cuándo y cómo llevar a cabo entrevistas de investigación con testigos y víctimas intoxicados, un grupo vulnerable. Conclusiones: Se recomienda la colaboración estrecha entre policía e investigadores para crear directrices para la investigación policial con personas intoxicadas.

The lack of robust evidence for the effects of alcohol on false memory.

We comment on Kloft et al.'s (2021) review of the effects of alcohol and other drugs on false memory reporting. Across studies, problems of internal and external validity and methodological consistency preclude any blanket conclusions and recommendations regarding alcohol's effects on false memory reporting and suggestibility in witnesses. We argue that any policy and practice conclusions drawn from this limited literature are premature and would be unfairly prejudicial to witnesses and confusing to triers of fact at this time.

Quality of Laypersons' Assessment of Forensically Relevant Stimuli.

The current study examined the potential for cognitive bias in lay examiners' comparisons of footwear impressions within the technical review process while addressing limitations of previous research. Prior research has found inconsistent results regarding the extent to which cognitive bias may influence forensic comparisons, often asking non-experts to review forensic stimuli above their competency level. Furthermore, past research has largely ignored the potential for cognitive bias during the technical review process. In collaboration with the Miami-Dade Police Department's Forensic Services Bureau, we examined the effects of previous examiners' level of experience and prior knowledge of the previous examiner's decision on the technical review stage of footwear impression stimuli. Before lay examiners were presented with pairs of known match and nonmatch footwear impressions, they were either told that an expert or a novice had previously examined them and determined them to be either a match, nonmatch, or inconclusive (plus a no-information condition). Participants then evaluated each pair of footwear impressions to make their own determinations of match, nonmatch, or inconclusive. Results support the technical review process for all decision types, as known nonmatch stimuli were generally more difficult for lay examiners to assess than known match stimuli. Knowledge of a prior examiner's decision and status was observed only when the prior decision was inconclusive, suggesting the need for inclusion of inconclusive decisions in future research examining cognitive bias in forensic examination.

Witnesses' memory for events and faces under elevated levels of intoxication.

Research on alcohol and witness memory has burgeoned over the last decade. However, most studies have tested participants at relatively low breath alcohol concentration (BAC) levels, unrepresentative of those encountered by officers in the field. To examine how higher intoxication levels might impair witness memory for events and faces, the current research tested participants' ability to recall a mock crime at elevated BAC levels (>.08%). The BAC levels of bar patrons (N = 138) were recorded before witnessing a video-taped mock crime. Participants were then interviewed using free recall and cued questions and shown a six-person target-present or target-absent lineup. Results show that alcohol negatively affected both the quantity and quality of recall. Regardless of question format, alcohol also reduced the percentage of accurate information elicited from witnesses; however, only cued questions increased the percentage of inaccurate information reported. Intoxication had no effect on identification accuracy. These findings suggest that the encoding and storage systems for faces and events may be impacted differently by alcohol. Our results also highlight the importance of including higher BAC levels when examining the effects of alcohol on witness memory.

The effect of encoding duration on implicit and explicit eyewitness memory.

The present study investigated the effect of encoding duration on implicit and explicit eyewitness memory. Participants (N = 227) viewed a mock crime (brief, 15-s vs. long, 30-s vs. irrelevant/control) and were then tested with both implicit and explicit memory prompts or with explicit memory prompts only. Brief-encoding participants revealed more critical details implicitly than long-encoding or control participants. Further, the number and percentage of accurate details recalled explicitly were higher for long-encoding than for brief-encoding participants. Implicit testing prior to explicit recall-as compared to completing a filler task-was detrimental to free recall performance. Interestingly, brief-encoding participants were significantly more likely to remember critical details implicitly but not explicitly than long-encoding participants. This is the first study to investigate implicit eyewitness memory for a multimodal mock crime. Findings are theoretically consistent with prior research on cognition while expanding upon the extant eyewitness memory and investigative interviewing literature.

Self-Reported Current Practices in Child Forensic Interviewing: Training, Tools, and Pre-Interview Preparation.

In child sexual abuse investigations, forensic interviewers within the Child Advocacy Center (CAC) model serve as neutral fact-finders for a team of professionals tasked with investigating and intervening in cases of alleged child sexual abuse. Although empirical evidence has led to the development of best-practice techniques and protocols, there is currently no universally adopted protocol in the field. The present research gathered detailed information from a national sample of real-world child forensic interviewers about their training and current practices, with a specific focus on assessing the information interviewers typically review prior to conducting child forensic interviews. Most notably, the survey revealed a lack of uniformity in interviewing protocols adopted and pre-interview preparation practices. Although rare, some interviewers reported using an allegation-blind interviewing approach, highlighting the need for future research on this and other under-studied techniques. Copyright © 2017 John Wiley & Sons, Ltd.

Witness memory and alcohol: The effects of state-dependent recall.

Many real-world eyewitnesses are under the influence of alcohol either at the time of the crime, the interview, or both. Only recently has empirical research begun to examine the effects of alcohol on witness memory, yielding mixed results. The present study tested the importance of state-dependent memory in the context of alcohol's effects on encoding versus retrieval of a witnessed event, while simultaneously informing real-world investigative practices: Should witnesses sober up before an interview? Participants (N = 249) were randomized to a control, placebo, or alcohol condition at encoding and to either an immediate retrieval condition (in the same state) or a 1-week delay control, placebo, or alcohol retrieval condition. They recalled a witnessed mock crime using open ended and cued recall formats. After a delay, witnesses intoxicated at both encoding and retrieval provided less accurate information than witnesses in sober or placebo groups at both times. There was no advantage of state-dependent memory but intoxicated witnesses were best when recalling immediately compared to 1 week later (sober, placebo, or reintoxicated). Findings have direct implications for the timing of intoxicated witnesses' interviews such that moderately intoxicated witnesses may not benefit from a sobering delay but rather, should be interviewed immediately. (PsycINFO Database Record

"Blind" interviewing: Is ignorance bliss?

Current investigative interviewing guidelines [e.g., Technical Working Group: Eyewitness evidence. (1999). Eyewitness evidence: A guide for law enforcement. U.S. Department of Justice, Office of Justice Programs, National Institute of Justice. Retrieved from https://www.ncjrs.gov/pdffiles1/nij/178240.pdf ] suggest that interviewers review available case information prior to conducting a witness interview. The present study investigated the effect of interviewers' pre-interview awareness of crime details on eyewitnesses' memory and interviewer behaviour shortly after a mock crime or a week later. Results indicate that blind interviewers with no knowledge about the crime elicited more correct information than those who were correctly informed about the crime. Differences in interviewer behaviour emerged only in the very first question of the interview: Blind interviewers were more likely to begin the interview with a non-suggestive question than the informed interviewers. Blind interviewers also recalled more details than the informed interviewers when asked to generate a report after the witness interview documenting the witness' account.

Examining the positive effects of rapport building: when and why does rapport building benefit adult eyewitness memory?

Most investigative interviewing protocols recommend building rapport with cooperative adult witnesses to increase the accuracy of their reports. Although a few recent studies support the benefits of rapport building on adult witness recall, no study has examined whether the timing of rapport in relation to post-event misinformation affects recall accuracy, and whether these effects are related to witness anxiety levels throughout the interview. The present study provided two hundred and thirty-three undergraduates with a videotaped mock crime followed by building high or low rapport either before or after they received post-event misinformation. All witnesses were then interviewed about the mock crime. Results indicated that high rapport before misinformation increased the amount of accurate information reported in a subsequent witness interview compared to low rapport. However, these recall benefits were not due to a reduction in anxiety. Theoretical implications and practical recommendations for police interviewing practices are discussed.