Knowledge about others reduces one's own sense of anonymity.

Social ties often seem symmetric, but they need not be1-5. For example, a person might know a stranger better than the stranger knows them. We explored whether people overlook these asymmetries and what consequences that might have for people's perceptions and actions. Here we show that when people know more about others, they think others know more about them. Across nine laboratory experiments, when participants learned more about a stranger, they felt as if the stranger also knew them better, and they acted as if the stranger was more attuned to their actions. As a result, participants were more honest around known strangers. We tested this further with a field experiment in New York City, in which we provided residents with mundane information about neighbourhood police officers. We found that the intervention shifted residents' perceptions of officers' knowledge of illegal activity, and it may even have reduced crime. It appears that our sense of anonymity depends not only on what people know about us but also on what we know about them.

Do digital technologies reduce racially biased reporting? Evidence from NYPD administrative data.

Recent work has emphasized the disproportionate bias faced by minorities when interacting with law enforcement. However, research on the topic has been hampered by biased sampling in administrative data, namely that records of police interactions with citizens only reflect information on the civilians that police elect to investigate, and not civilians that police observe but do not investigate. In this work, we address a related bias in administrative police data which has received less empirical attention, namely reporting biases around investigations that have taken place. Further, we investigate whether digital monitoring tools help mitigate this reporting bias. To do so, we examine changes in reports of interactions between law enforcement and citizens in the wake of the New York City Police Department's replacement of analog memo books with mobile smartphones. Results from a staggered difference in differences estimation indicate a significant increase in reports of citizen stops once the new smartphones are deployed. Importantly, we observe that the rise is driven by increased reports of "unproductive" stops, stops involving non-White citizens, and stops occurring in areas characterized by a greater concentration of crime and non-White residents. These results reinforce the recent observation that prior work has likely underestimated the extent of racial bias in policing. Further, they highlight that the implementation of digital monitoring tools can mitigate the issue to some extent.

The secret life of crime labs.

Houston TX experienced a widely known failure of its police forensic laboratory. This gave rise to the Houston Forensic Science Center (HFSC) as a separate entity to provide forensic services to the City of Houston. HFSC is a very large forensic laboratory and has made significant progress at remediating the past failures and improving public trust in forensic testing. HFSC has a large and robust blind testing program, which has provided many insights into the challenges forensic laboratories face. HFSC's journey from a notoriously failed lab to a model also gives perspective to the resource challenges faced by all labs in the country. Challenges for labs include the pervasive reality of poor-quality evidence. Also that forensic laboratories are necessarily part of a much wider system of interdependent functions in criminal justice making blind testing something in which all parts have a role. This interconnectedness also highlights the need for an array of oversight and regulatory frameworks to function properly. The major essential databases in forensics need to be a part of blind testing programs and work is needed to ensure that the results from these databases are indeed producing correct results and those results are being correctly used. Last, laboratory reports of "inconclusive" results are a significant challenge for laboratories and the system to better understand when these results are appropriate, necessary and most importantly correctly used by the rest of the system.

Enabling witnesses to actively explore faces and reinstate study-test pose during a lineup increases discriminability.

Accurate witness identification is a cornerstone of police inquiries and national security investigations. However, witnesses can make errors. We experimentally tested whether an interactive lineup, a recently introduced procedure that enables witnesses to dynamically view and explore faces from different angles, improves the rate at which witnesses identify guilty over innocent suspects compared to procedures traditionally used by law enforcement. Participants encoded 12 target faces, either from the front or in profile view, and then attempted to identify the targets from 12 lineups, half of which were target present and the other half target absent. Participants were randomly assigned to a lineup condition: simultaneous interactive, simultaneous photo, or sequential video. In the front-encoding and profile-encoding conditions, Receiver Operating Characteristics analysis indicated that discriminability was higher in interactive compared to both photo and video lineups, demonstrating the benefit of actively exploring the lineup members' faces. Signal-detection modeling suggested interactive lineups increase discriminability because they afford the witness the opportunity to view more diagnostic features such that the nondiagnostic features play a proportionally lesser role. These findings suggest that eyewitness errors can be reduced using interactive lineups because they create retrieval conditions that enable witnesses to actively explore faces and more effectively sample features.

Improving forensic perpetrator identification with Super-Recognizers.

About a decade ago, Super-Recognizers (SRs) were first described as individuals with exceptional face identity processing abilities. Since then, various tests have been developed or adapted to assess individuals' abilities and identify SRs. The extant literature suggests that SRs may be beneficial in police tasks requiring individual identification. However, in reality, the performance of SRs has never been examined using authentic forensic material. This not only limits the external validity of test procedures used to identify SRs, but also claims concerning their deployment in policing. Here, we report the first-ever investigation of SRs' ability to identify perpetrators using authentic case material. We report the data of 73 SRs and 45 control participants. These include (a) performance on three challenging tests of face identity processing recommended by Ramon (2021) for SR identification; (b) performance for perpetrator identification using four CCTV sequences depicting five perpetrators and police line-ups created for criminal investigation purposes. Our findings demonstrate that the face identity processing tests used here are valid in measuring such abilities and identifying SRs. Moreover, SRs excel at perpetrator identification relative to control participants, with more correct perpetrator identifications, the better their performance across lab tests. These results provide external validity for the recently proposed diagnostic framework and its tests used for SR identification (Ramon, 2021). This study provides the first empirical evidence that SRs identified using these measures can be beneficial for forensic perpetrator identification. We discuss theoretical and practical implications for law enforcement, whose procedures can be improved via a human-centric approach centered around individuals with superior abilities.

Escalated police stops of Black men are linguistically and psychologically distinct in their earliest moments.

Across the United States, police chiefs, city officials, and community leaders alike have highlighted the need to de-escalate police encounters with the public. This concern about escalation extends from encounters involving use of force to routine car stops, where Black drivers are disproportionately pulled over. Yet, despite the calls for action, we know little about the trajectory of police stops or how escalation unfolds. In study 1, we use methods from computational linguistics to analyze police body-worn camera footage from 577 stops of Black drivers. We find that stops with escalated outcomes (those ending in arrest, handcuffing, or a search) diverge from stops without these outcomes in their earliest moments-even in the first 45 words spoken by the officer. In stops that result in escalation, officers are more likely to issue commands as their opening words to the driver and less likely to tell drivers the reason why they are being stopped. In study 2, we expose Black males to audio clips of the same stops and find differences in how escalated stops are perceived: Participants report more negative emotion, appraise officers more negatively, worry about force being used, and predict worse outcomes after hearing only the officer's initial words in escalated versus non-escalated stops. Our findings show that car stops that end in escalated outcomes sometimes begin in an escalated fashion, with adverse effects for Black male drivers and, in turn, police-community relations.

Protection against Omicron from Vaccination and Previous Infection in a Prison System.

BACKGROUND: Information regarding the protection conferred by vaccination and previous infection against infection with the B.1.1.529 (omicron) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is limited. METHODS: We evaluated the protection conferred by mRNA vaccines and previous infection against infection with the omicron variant in two high-risk populations: residents and staff in the California state prison system. We used a retrospective cohort design to analyze the risk of infection during the omicron wave using data collected from December 24, 2021, through April 14, 2022. Weighted Cox models were used to compare the effectiveness (measured as 1 minus the hazard ratio) of vaccination and previous infection across combinations of vaccination history (stratified according to the number of mRNA doses received) and infection history (none or infection before or during the period of B.1.617.2 [delta]-variant predominance). A secondary analysis used a rolling matched-cohort design to evaluate the effectiveness of three vaccine doses as compared with two doses. RESULTS: Among 59,794 residents and 16,572 staff, the estimated effectiveness of previous infection against omicron infection among unvaccinated persons who had been infected before or during the period of delta predominance ranged from 16.3% (95% confidence interval [CI], 8.1 to 23.7) to 48.9% (95% CI, 41.6 to 55.3). Depending on previous infection status, the estimated effectiveness of vaccination (relative to being unvaccinated and without previous documented infection) ranged from 18.6% (95% CI, 7.7 to 28.1) to 83.2% (95% CI, 77.7 to 87.4) with two vaccine doses and from 40.9% (95% CI, 31.9 to 48.7) to 87.9% (95% CI, 76.0 to 93.9) with three vaccine doses. Incremental effectiveness estimates of a third (booster) dose (relative to two doses) ranged from 25.0% (95% CI, 16.6 to 32.5) to 57.9% (95% CI, 48.4 to 65.7) among persons who either had not had previous documented infection or had been infected before the period of delta predominance. CONCLUSIONS: Our findings in two high-risk populations suggest that mRNA vaccination and previous infection were effective against omicron infection, with lower estimates among those infected before the period of delta predominance. Three vaccine doses offered significantly more protection than two doses, including among previously infected persons.

Protest movements involving limited violence can sometimes be effective: Evidence from the 2020 BlackLivesMatter protests.

SignificanceThe effects of recent protests for racial equality, particularly when they included violence, are currently of public and academic interest. To better understand these effects, we combine a dataset of all 2020 BlackLivesMatter protests with survey data containing measures of prejudice and support for police reform. Protests were not associated with reductions in prejudice, but were associated with increases in support for police reform. Specifically, a mix of nonviolent and violent protests was associated with an increase in police-reform support among conservatives living in liberal areas. This study highlights the importance of considering multiple measures of protest effectiveness and suggests that mass protest (including when it mixes nonviolence and violence) can be effective at advancing the movement's goals.

Police agencies on Facebook overreport on Black suspects.

A large and growing share of the American public turns to Facebook for news. On this platform, reports about crime increasingly come directly from law enforcement agencies, raising questions about content curation. We gathered all posts from almost 14,000 Facebook pages maintained by US law enforcement agencies, focusing on reporting about crime and race. We found that Facebook users are exposed to posts that overrepresent Black suspects by 25 percentage points relative to local arrest rates. This overexposure occurs across crime types and geographic regions and increases with the proportion of both Republican voters and non-Black residents. Widespread exposure to overreporting risks reinforcing racial stereotypes about crime and exacerbating punitive preferences among the polity more generally.

The language of less-lethal weapons.

It has been over 1 year since we observed the policing of the George Floyd protests in the United States [R. R. Hardeman, E. M. Medina, R. W. Boyd, N. Engl. J. Med. 383, 197-199 (2020)]. Multiple injury reports emerged in medical journals, and the scientific community called for law enforcement to discontinue the use of less-lethal weapons [E. A. Kaske et al., N. Engl. J. Med. 384, 774-775 (2021) and K. A. Olson et al., N. Engl. J. Med. 383, 1081-1083 (2020)]. Despite progress in research, policy change has not followed a similar pace. Although the reasoning for this discrepancy is multifactorial, failure to use appropriate language may be one contributing factor to the challenges faced in updating policies and practices. Here, we detail how language has the potential to influence thinking and decision-making, we discuss how the language of less-lethal weapons minimizes harm, and we provide a framework for naming conventions that acknowledges harm.

Beliefs about minority representation in policing and support for diversification.

Diversification of police forces is widely promoted as a reform for reducing racial disparities in police-civilian interactions and increasing police legitimacy. Despite these potential benefits, nearly every municipal police department in the United States remains predominately White and male. Here, we investigate whether the scale and persistence of minority underrepresentation in policing might partly be explained by a lack of support for diversification among voters and current police officers. Across two studies (N = 2, 661) sampling the US adult population and residents from a city with one of the least representative police forces in the country, individuals significantly overestimate officer diversity at both the local and national levels. We find that correcting these biased beliefs with accurate information reduces trust in police and increases support for hiring new officers from underrepresented groups. In the municipal sample, these corrections also cause an increase in residents' willingness to vote for reforms to diversify their majority White police department. Additional paired decision-making experiments (N = 1, 663) conducted on these residents and current police officers demonstrate that both prefer hiring new officers from currently underrepresented groups, independent of civil service exam performance and other hiring criteria. Overall, these results suggest that attitudes among voters and police officers are unlikely to pose a major barrier to diversity reforms.

Reforming the police through procedural justice training: A multicity randomized trial at crime hot spots.

SignificanceOur study is a randomized trial in policing confirming that intensive training in procedural justice (PJ) can lead to more procedurally just behavior and less disrespectful treatment of people at high-crime places. The fact that the PJ intervention reduced arrests by police officers, positively influenced residents' perceptions of police harassment and violence, and also reduced crime provides important guidance for police reform in a period of strong criticism of policing. This randomized trial points to the potential for PJ training not simply to encourage fair and respectful policing but also to improve evaluations of the police and crime prevention effectiveness.

Sleep Problems Among Black Youth Exposed to Police Violence on Digital Media.

Findings from a recent survey of a community-based sample of Black youth ages 12 through 21 in Baltimore City, Maryland (n = 345) reveal that viewing fatal police violence videos is associated with significant increases in the odds of youth sleep disturbances, and about 30% of this association is attributable to emotional distress after viewing the videos.

A novel test and treat program for hepatitis C virus infection utilizing HCV core antigen testing, among police and general population, Islamabad, Pakistan, 2022.

Hepatitis C virus core antigen (HCVcAg) testing can simplify and decrease costs of HCV infection confirmation compared to molecular testing (nucleic acid testing). We piloted HCVcAg testing for the confirmation of active infection. The study was conducted during June through December 2022 among the police and the general population of Islamabad, Pakistan age 18 years and older. Initial screening for HCV antibody was conducted using a rapid diagnostic test (RDT) for all consenting participants. Those who tested positive had venous blood samples tested for HCVcAg, platelets and aspartate aminotransferase (AST). Persons with HCVcAg values ≥3 fmol/L were defined as viremic, and they were offered treatment with direct acting antiviral (DAA) medications, sofosbuvir and daclatasvir. Aspartate aminotransferase to platelet ratio index (APRI) was calculated for each HCV infected person, and those with an APRI score <1.5 received treatment for 12 weeks, while those with APRI ≥ to 1.5 received 24 weeks of treatment. A total of 15,628 persons were screened for anti-HCV using RDT and 643 (4.1%) tested positive. HCVcAg values of ≥3 fmol/L was found in 399/643 (62.1%), and all were offered and accepted treatment. Of those treated, 273/399 (68.4%) returned for a follow-up SVR and HCVcAg was not detected in 261/273, a 95.6% cure rate. The pilot study demonstrated the effectiveness of reaching and treating an urban population using RDT for screening and HCVcAg for confirmation of infection and test of cure.

Assessing Verbal Eyewitness Confidence Statements Using Natural Language Processing.

After an eyewitness completes a lineup, officers are advised to ask witnesses how confident they are in their identification. Although researchers in the lab typically study eyewitness confidence numerically, confidence in the field is primarily gathered verbally. In the current study, we used a natural language-processing approach to develop an automated model to classify verbal eyewitness confidence statements. Across a variety of stimulus materials and witnessing conditions, our model correctly classified adult witnesses' (N = 4,541) level of confidence (i.e., high, medium, or low) 71% of the time. Confidence-accuracy calibration curves demonstrate that the model's confidence classification performs similarly in predicting eyewitness accuracy compared to witnesses' self-reported numeric confidence. Our model also furnishes a new metric, confidence entropy, that measures the vagueness of witnesses' confidence statements and provides independent information about eyewitness accuracy. These results have implications for how empirical scientists collect confidence data and how police interpret eyewitness confidence statements.

Order Keepers or Immigration Agents? Latine Immigrant Views of Law Enforcement in Healthcare Settings.

BACKGROUND: Police and security presence in healthcare settings have grown. There are few studies exploring perceptions of these law enforcement agents among US Latine immigrants, who can be vulnerable to immigration enforcement actions due to past and ongoing criminalization and anti-immigrant policies. OBJECTIVE: To explore Latine immigrants' perceptions of law enforcement in healthcare settings. DESIGN: Exploratory, semi-structured qualitative interviews asked participants about their perspectives of law enforcement in healthcare settings. PARTICIPANTS: English- and Spanish-speaking adult patients (n = 19) from a Federally Qualified Health Center (FQHC) in Los Angeles, CA, serving predominantly low-income Latine immigrants. APPROACH: We used the framework method for analysis to establish a codebook and inform our thematic interpretation. KEY RESULTS: We identified three themes: (1) perceptions of safety offered by police officers are separated from the role of immigration officers; (2) perceptions of police officers are integrated into broader perceptions of the healthcare system; and (3) lived experiences, including immigration status, influenced valence response to officer uniforms and perceptions of officers. Most participants viewed police officers positively as maintaining order and safety, separating them from federal immigration enforcement actions, and reflecting on local, state, and organizational "sanctuary" or immigrant-friendly policies. Individuals with precarious immigration status more often saw officers as intimidating. Immigration enforcement remained a key concern. CONCLUSIONS: Differentiating police and security roles from immigration enforcement in healthcare could improve Latine immigrant trust and access. Future studies should explore perspectives of Latine immigrants in localities without sanctuary laws or organizational immigrant-friendly policies.

National Burden of Injury and Deaths From Shootings by Police in the United States, 2015‒2020.

Objectives. To describe all-outcome injurious shootings by police and compare characteristics of fatal versus nonfatal injurious shootings nationally. Methods. From July 2021 to April 2023, we manually reviewed publicly available records on all 2015-2020 injurious shootings by US police, identified from Gun Violence Archive. We estimated injury frequency, case fatality rates, and relative odds of death by incident and victim characteristics. Results. A total of 1769 people were injured annually in shootings by police, 55% fatally. When a shooting injury occurred, odds of fatality were 46% higher following dispatched responses than police-initiated responses. Injuries associated with physically threatening or threat-making behaviors, behavioral health needs, and well-being checks were most frequently fatal. Relative to White victims, Black victims were overrepresented but had 35% lower odds of fatal injury when shot. Conclusions. This first multiyear, nationwide analysis of injurious shootings by US police suggests that injury disparities are underestimated by fatal shootings alone. Nonpolicing responses to social needs may prevent future injuries. Public Health Implications. We call for enhanced reporting systems, comprehensive evaluation of emerging reforms, and targeted investment in social services for equitable injury prevention. (Am J Public Health. 2024;114(4):387-397. https://doi.org/10.2105/AJPH.2023.307560).

Detect, Dispatch, Drive: A Study of ShotSpotter Acoustic Technology and Transport of Gunshot Victims.

INTRODUCTION: Our previous work demonstrated that use of ShotSpotter (SS), a gunfire detection system, and use of police department (PD) transport decreased response and transport time for gunshot wound (GSW) victims versus events with non-ShotSpotter (NSS). The purpose of this study was to evaluate transport trends and how they are linked to SS in the period of 2016-2021 in Camden, NJ. METHODS: This was a single-center, retrospective observational study. Demographics, response time, transport time, and clinical data were collected. Independent t-test, Mann-Whitney U test, chi-squared test, and linear regression to correct for transport time and method of transport were used to compare outcomes (P < 0.05). RESULTS: A total of 267 GSWs were included: 77 emergency medical technicians (EMS)-SS, 41 EMS-NSS, 116 PD-SS, and 33 PD-NSS. When comparing response from 2016 to 2021, PD improved from 4 to 2 min (P = 0.001). EMS improved from 6.4 min (EMS-NSS) and 4.5 min (EMS-SS) to 5 min (EMS- NSS) and 4 min (EMS-SS) (P = 0.281). In addition, PD transport times, 5 min (SS) and 4 min (NSS), were faster than EMS, 9 min (SS and NSS) (P < 0.001). Overall PD transport volume increased with a peak in 2020 (68.3%). There was also an increase in PD-NSS transport 4% to 37.9% (P < 0.001). EMS-SS transport decreased from 54.7% to 6.9% (P < 0.001). CONCLUSION: The presence of SS technology in a small urban setting continues to be associated with a higher rate of PD transport of GSW victims. The critical time of dispatch and transport for both PD and EMS has shown durable improvement.

Awareness of forensic anthropology in Switzerland: a survey among forensic practitioners, police, and prosecutors.

Forensic anthropology (FA) as a specialized discipline has been practised in multi-lingual Switzerland for over a decade. A variety of expertise regarding osteological assessments as well as facial image comparison (FIC) is provided by different centres. Nevertheless, information is lacking about the awareness of FA and its benefits for forensic investigations among forensic stakeholders. Therefore, a survey was sent to Swiss anthropologists (AN) and related professions (police officers, prosecutors, and forensic pathologists) to assess three main aspects: (1) the experience of working (biological/forensic) anthropologists within FA; (2) how FA is perceived by other professions within the legal system; and (3) identify gaps (if any) in understanding of FA with the aim to suggest avenues for improvement if necessary. The results show that awareness of FA varies by occupation and cantonal regions. In areas where close collaborations between forensic anthropologists (FAs) and other stakeholders have been formally established, be it with focus on osteological analyses or FIC, the awareness of FA competencies was superior to areas where this was not the case. An overwhelming majority of forensic actors expressed interest in continuing education related to the role of FA. These findings indicate that facilitation of communication and collaboration leads to improvement in the awareness of the competencies of FAs and their contribution to forensic investigations.

Prosecuting cases of abusive head trauma in Switzerland: a descriptive study of the impact of medical documentation and delay of reporting on judicial outcome.

Abusive head trauma (AHT) is a criminal offence that is prosecuted ex officio, following report to the police from physicians or child protection services. The aim of this study was to assess whether the judicial outcome (dismissal vs indictment) was influenced by the quality of the medical documentation and/or the time span between AHT diagnosis and reporting child abuse to the police. The cohort was divided in two groups: 13/23 dismissals (57%) and 10/23 indictments (43%). The diagnostic probability of the AHT cases was certain for both groups. Nonetheless, in fraction of dismissed cases, alternative explanations for the observed lesions seemed plausible to the public prosecutor. Legal files of only 3/12 dismissed cases had a forensic report, while 6/10 cases that were indicted included a forensic report. Further, the legal file of several dismissed cases entirely lacked medical documentation (3/12), which was not the cases for indicted cases. The period between AHT diagnosis and reporting to the police was not different for dismissals (29 ± 19 days) and indictments (7 ± 4 days) (p = 0.32). Physicians filed reports more rapidly (6 ± 1 days) compared to childhood protection service (70 ± 46 days) (p = 0.01) and that may increase the rate of indictments (9/18) compared to reporting via the childhood protection service (1/5). Despite diagnostic certainty, other causes for the lesions were considered as plausible alternative explanations to judicial professionals in several dismissed cases. These seemed to have less medical documentation and forensic evaluations. In addition, more rapid reporting to the police by physicians seems to increase the likelihood of indictments.