By Aaron Chalfin and Felipe Goncalves

  How do public sector workers balance their pro-social motivations with private interests? In this study of police officers, we exploit two institutional features that change the implicit cost of making an arrest: arrests made near the end of an officer’s shift are more likely to require overtime work, and arrests made on days when an officer “moonlights” at an off-duty job after their shift have a higher opportunity cost. We document two consequences for officer behavior. First, contrary to popular wisdom, officers reduce arrests near the end of their shift, and the quality of arrests increases. We argue that these patterns are driven by officer preferences rather than departmental policy, fatigue, or incapacitation from earlier arrests. Second, officers further reduce late-shift arrests on days in which they moonlight after work, suggesting that they are, in fact, modestly responsive to financial incentives. Using these results, we estimate a dynamic model that identifies an officer’s implied trade-off between private and pro-social motivations. We find that police officers exhibit high pro-social motivation towards their work. In contrast to prior research showing that law enforcement outcomes are sensitive to financial incentives at an institutional level, the behavior of individual officers — the “street-level bureaucrats” who enforce the law — is not meaningfully distorted by monetary considerations.

Unpublished paper, 2020. 74p.

By P. Jeffrey Brantingham and Craig D. Uchida

Calls-for-service represent the most basic form of public cooperation with the police. How cooperation varies as a function of instances of police activity remains an open question. The great situational diversity of police activity in the field, matching the situational diversity of crime and disorder, makes it challenging to estimate causal effects. Here we use homicides as an indicator for the occurrence of a standardized set of highly visible, socially-intensive, acute police investigative activities and examine whether police calls-for-service change in response. We adopt a place-based difference-in-differences approach that controls for local fixed affects and common temporal trends. Estimates of the model using data from Los Angeles in 2019 shows that calls-for-service increase significantly in the week following a homicide. The effect pertains to both violent crime and quality of life calls for service. Partitioning the data by race-ethnicity shows that calls-for-service increase most when the homicide victim is Black. Partitioning the data by race-ethnicity and type of homicide shows that some types of calls are suppressed when the homicide is gang-related. The results point to opportunities for police to build trust in the immediate aftermath of homicides, when the public is reaching out for greater assistance.

Journal of Criminal Justice, 73:2021.

By Conor Casey

This report considers the constitutional role of the Law Officers and defends the institutional status quo. The current configuration of the Attorney General (and Solicitor General), as a law officer with legal and political dimensions, works well. Moving to an alternative (apolitical, technocratic) model of Attorney General would risk excessive legalisation of policy and would reduce political accountability.

London: Policy Exchange, 2023. 29p.

By Betsy Pearl

  In recent years, a series of high-profile cases of police violence—from Michael Brown, Tamir Rice and Eric Garner to George Floyd, Breonna Taylor, and Jacob Blake—has brought to the national consciousness concerns that have been prevalent among many activists, researchers, and policymakers: What should we expect of the police? Who is responsible for public safety? And what does it mean to invest in safety beyond policing? The traditional understanding of public safety in the United States has revolved almost exclusively around policing, which is demonstrated by the size of the footprint of police agencies and their corresponding budgets. For example, the number of police officers nationwide has grown by 36 percent in two decades—from less than 700,000 officers in 1990 to more than 950,000 in 2012. As the size of American police forces grew, so too did their role in the community. “Efforts to address underlying community problems through social investment took a backseat [to] policing strategies,” noted political scientists Joe Soss and Vesla Weaver. The duties of the modern police force now extend well beyond enforcing the law, to include tasks from treating overdoses and de-escalating behavioral health crises to addressing homelessness and responding to disciplinary concerns in schools. Law enforcement now spends only a fraction of their time responding to issues of violence: American police officers make more than 10 million arrests each year, less than 5 percent of which are for serious violent crimes. The impact of police force expansion on community safety is debatable at best. While determining the cause of crime rate fluctuations is a notoriously difficult task, an analysis from the Brennan Center for Justice finds that the increase in officers had only a modest effect on crime rates in the 1990s, accounting for between 0 percent and 10 percent of the total crime reduction. Police growth continued between 2000 and 2012, with no discernible effect on crime rates. Instead, societal factors, such as growth in income, likely played a more important part in reducing crime rates during the 1990s and 2000s. Sociologist Patrick Sharkey has also analyzed factors contributing to crime reductions between 1990 and 2012, concluding that community-based organizations likely played a “substantial role in explaining the decline in violence” during this time period. In a city of 100,000 people, every new nonprofit focused on neighborhood safety and wellness was associated with an estimated 1 percent reduction in violent crime and homicide. ...

Washington, DC: Center for American Progress, 2020. 37p.

By Adrian Cherney, Emma Antrobus, Sarah Bennett, Bevan Murphy and Mike Newman

Evidence-based policing (EBP) advocates the use of scientific processes in police decision-making. This paper examines results from a survey of officers in the Queensland Police Service and the Western Australia Police on the uptake of and receptiveness towards EBP research. Using a combined dataset, the paper examines a variety of factors related to the perceived value and usefulness of academic and internal research, and individual and organisational barriers to the use of EBP research. It also explores whether leadership and EBP workshops influence the adoption of evidence-based practices.

Canberra: Australian Institute of Criminology, 2019. 18p.

By Deborah Witzburg and Tobara Ricihardson

  As mandated by the consent decree entered in Illinois v. Chicago, the Public Safety section of the City of Chicago Office of Inspector General (OIG) has conducted an inquiry into the enforcement of the Chicago Police Department’s (CPD or the Department) Rule 14, which prohibits CPD members from “[m]aking a false report, written or oral.”1 Alleged violations of CPD’s Rules and Regulations are usually investigated by CPD’s Bureau of Internal Affairs (BIA) and by the Civilian Office of Police Accountability (COPA), with the most serious of police disciplinary cases being adjudicated by the Chicago Police Board.2 All of these entities come within the scope of OIG’s inquiry into the enforcement of CPD’s rule against false reports. The truthfulness and credibility of police officers is foundational to the fair administration of justice, and to CPD’s effectiveness as a law enforcement agency. CPD, COPA, and the Police Board have each publicly expressed the view that these qualities in CPD members are integral to their ability to perform their duties and that a member’s violation of Rule 14 poses important risks, including undermining their ability to offer testimony in criminal prosecutions arising from CPD’s arrests. Due to the severity of the impact that stems from a CPD member making a false statement or report, CPD and COPA have reported the position that separation (i.e., termination of employment) is the appropriate disciplinary penalty when a member is found to have violated Rule 14.   

Chicago: City of Chicago, Office of inspector General, 2023. 61p.

By Travis Carter, Jedidiah Knode and Scott Wolfe  

This report presents the results from a racial/ethnic disparity analysis of Michigan State Police (MSP) traffic stops conducted in 2021. The goal of the analysis is to identify the extent of racial/ethnic disparities in MSP traffic stop behavior across MSP worksites (i.e., posts). The analyses are based on a leading empirical approach to assessing racial/ethnic disparities in traffic stop behavior—the veil-of-darkness (VOD). The analyses account for important structural differences across posts and their jurisdictions, such as the rate of violent crime and troopers per capita, as well as temporal factors that may shape traffic patterns and stop behavior (e.g., time of day, day of week) to help ensure the results are as informative as possible. Below, we briefly outline the methodology employed and summarize the main findings. When discussing the results from this report, it is important to recognize the difference between “disparity” and “discrimination.” Disparity in these traffic stop analyses refers to differences in racial/ethnic group representation based on presumed visibility of the driver. Disparity cannot identify intent, whereas discrimination inherently involves intent. Therefore, discrimination in traffic stop behavior refers to police officers intentionally stopping individuals based on their status in a racial/ethnic minority group. Discrimination can generate disparities by way of differential treatment of racial/ethnic groups, but disparities may also be the result of nondiscriminatory (e.g., environmental, situational, etc.) factors such as crime prevalence and driving pattern differences. This report and its findings can speak only to the extent of racial/ethnic disparity in MSP traffic stops. The data cannot ascertain whether racially discriminatory practices are occurring within MSP. Although disentangling disparity from bias is critical towards improving police practices, accurately identifying the existence of such disparity and its magnitude is an important precursor to this process. More information on the data collection process is provided in the body of the report. Next, we highlight the main takeaways from the analyses.   

East Lansing:  Michigan Justice Statistics Center School of Criminal Justice Michigan State University, 2022. 33p.

By David Weisburd, David B. Wilson, Kevin Petersen, Cody W. Telep

The Kansas City Preventive Patrol Experiment (KCPPE) was seen by its developers to have produced “consistent evidence of the lack of effects of any consequence on crime,” a conclusion that was to have a strong impact on assumptions about police patrol for almost half a century. We identified the original official crime data from the KCPPE, and reanalyzed outcomes focusing on a comparison of the “proactive” versus “control” beats (“reactive beats” were criticized because of violations of treatment integrity); examining broad categories of crime (to increase statistical power); and using count regression models. Our findings are not unequivocal, but point to modest impacts of police patrol on crime in police beats.

Policy Implications: Our findings suggest that lessons drawn for half a century from the KCPPE need to be revisited. The KCPPE does not show that police patrol in large areas has no influence on crime, and this finding is consistent with several more recent studies. At the same time, we note that the effects of patrol in the KCPPE using our analysis strategy, and those found in other studies of preventive patrol in larger areas, are about half that found in hot spots policing studies. This suggests that police agencies ideally should invest in focused hot spots policing initiatives. However, absent an ability to manage such initiatives, or the crime analysis capabilities to identify crime hot spots routinely, simpler preventive patrol schemes to utilize uncommitted patrol time can be seen as potentially effective in preventing crime.

Criminology and Public Policy,  2023: 1-18

By Gabrielle T. Isaza, Robin Engel and Jennifer Calnon Cherkauskas 

Sobering centers offer a unique opportunity to reduce arrests for vulnerable populations while removing a person from a potentially dangerous situation. Despite the long and complex history of their use, little is known systematically about the effectiveness of sobering centers as an alternative to arrest. Only a handful of studies have examined the impacts of sobering centers on the criminal justice system, and these studies typically focus on a single site. To build the evidence on sobering centers, Arnold Ventures funded our research study assessing the utility of sobering centers as an alternative to arrest. This report is the first in a series detailing our multi-method and multi-site research study, launched in January 2020. In this research study, examine four primary research questions: 1. What are the patterns of policies and practices for police use of sobering centers as an alternative to arrest? What guides this decision-making? 2. What are the situational factors police use in practice to determine whether or not to use sobering centers as an alternative to arrest? 3. How do police balance and overcome policy and legal inconsistencies guiding the transport to and use of sobering centers? 4. When individuals are sent to sobering centers in lieu of arrest, does it alter their relative risk of recidivism or future contact with police? This report focuses on the quantitative findings of Phase I, disclosing the results of two national surveys—one for law enforcement agencies and one for sobering center facilities. Survey findings shed light on how police use sobering centers and the perceived benefits and barriers to their use. In turn, the survey findings also provide important insights on how to build effective partnerships and enhance the utility of sobering centers as an alternative to arrest.  

Arlington VA: National Policing Institute, 2022. 78p.

By Robin S. Engel,  Jennifer Calnon Cherkauskas, Nicholas Corsaro, Murat Yildirim

In 2002, the Pennsylvania State Police (PSP) was one of the first state police agencies to initiate traffic stop data collection voluntarily. The current data collection effort is based on foundational work conducted with the same research team for more than a decade, beginning with initial planning in 1999. After discontinuing the data collection program in 2011, the PSP renewed its traffic stop data collection effort in 2021, which now continues in partnership with the National Policing Institute (the Institute). Given the variety of factors involved in police stop and enforcement decisions, it is beneficial for agencies to identify and better understand trends and patterns to enhance their ability to interact with the public safely and fairly. The voluntary collection and analysis of traffic stop data is consistent with recommended best practice, demonstrates dedication to transparency and accountability to the public, and continues the PSP’s commitment to evidence-based policing practices. This report documents the findings from statistical analyses of data collected during all member-initiated traffic stops by the PSP from January 1, 2022 – December 31, 2022. These data are reported by individual troopers after each member-initiated traffic stop, gathered and compiled by the PSP, and transmitted weekly to the Institute’s research team. Throughout each section of this report, information is presented at multiple organizational levels, reflecting the PSP’s organizational structure consisting of four Areas, 16 Troops, and 88 Stations. Presenting information in this manner illustrates differences and similarities across organizational units. It permits the identification of organizational and geographic groups that may appear as outliers, providing opportunities for closer examination and focused attention by PSP officials.  

Arlington, VA: National Policing Institute, 2023. 169p.

By Johann Koehler, Tony Cheng
We show how both the Chicago Police Department and the New York Police Department sought to settle uncertainty about their propriety and purpose during a period when abrupt transformations destabilized urban order and called the police mandate into question. By comparing annual reports that the Chicago Police Department and the New York Police Department published from 1877 to 1923, we observe two techniques in how the police enacted that settlement: identification of the problems that the police believed themselves uniquely well equipped to manage and authorization of the powers necessary to do so. Comparison of identification and authorization yields insights into the role that these police departments played in convergent and divergent constructions of disorder and, in turn, into Progressivism's varying effects in early urban policing.

Criminology, 2023:1-28

By Shani A Buggs , Daniel W Webster, Cassandra K Crifasi  

Objective To estimate the long-term impact of Safe Streets Baltimore, which is based on the Cure Violence outreach and violence interruption model, on firearm violence. Methods We used synthetic control methods to estimate programme effects on homicides and incidents of non-fatal penetrating firearm injury (non-fatal shootings) in neighbourhoods that had Safe Streets’ sites and model-generated counterfactuals. Synthetic control analyses were conducted for each firearm violence outcome in each of the seven areas where Safe Streets was implemented. The study also investigated variation in programme impact over time by generating effect estimates of varying durations for the longest-running programme sites. Results Synthetic control models reduced prediction error relative to regression analyses. Estimates of Safe Streets’ effects on firearm violence varied across intervention sites: some positive, some negative and no effect. Beneficial programme effects on firearm violence reported in prior research were found to have attenuated over time. Conclusions For highly targeted interventions, synthetic control methods may provide more valid estimates of programme impact than panel regression with data from all city neighbourhoods. This research offers new understanding about the effectiveness of the Cure Violence intervention over extended periods of time in seven neighbourhoods. Combined with existing Cure Violence evaluation literature, it also raises questions about contextual and implementation factors that might influence programme outcomes.  

  Inj Prev 2022;28:61–67  

By Elizabeth Luh  

  Biased highway troopers may intentionally misreport the race of the stopped motorists in order to evade detection. I develop a new model of traffic stops that highlights the incentive for biased troopers to misreport their failed minority searches as White. Applying my model to the universe of highway searches in Texas from 2010–2015, I find evidence of widespread bias that varies substantially across troopers. Furthermore, misreporting increased the Hispanic search success rate by 17%. When misreporting became more difficult due to public scrutiny, misreporting troopers faced worse labor outcomes. This suggests an important role for increased accountability in data collection by law enforcement agents.

Unpublished paper, 2022. 54p.

By Danielle Watson · Loene Howes · Sinclair Dinnen · Melissa Bull · Sara N. Amin

This open access book brings together insights into Pacific policing, conceptualising policing broadly as order maintenance involving the actions of multiple local, regional and international actors with sometimes competing and conflicting agendas. A complex and multifaceted endeavour, scholarship on this topic is relatively scarce and widely dispersed across diverse sources. It examines how Pacific policing is shaped by changing state-society relations in different national contexts and ongoing processes of globalisation. Particular attention is given to the plural character of Pacific policing, profound challenges of gender equity, changing dynamics of crime, and the prominence of transnational policing in resource and capacity constrained domestic environments. The authors draw on examples from across the Pacific islands to provide a nuanced and contextualised account of policing in this socially diverse and rapidly transforming region.

Cham: Palgrave Macmillan, 2023. 208p

By Max Kapustin, Terrence Neumann and Jens Ludwig

How can we get more ‘output,’ and of the right sort, from policing? The question has only taken on greater importance with recent, widely publicized instances of police misconduct; declines in public trust in police; and a rise in gun violence, all disproportionately concentrated in economically disadvantaged communities of color. Research typically focuses on two levers: (1) police resources, and (2) policing strategies or policies, historically focused on crime control but increasingly also on accountability, transparency, and fairness. Here we examine a third lever: management quality. We present three types of evidence. First, we show there is substantial variability in violent crime and police use of force both across cities and within a city across police districts, and that this variation is related to the timing of police leader tenures. Second, we show that an effort to change police management in selected districts in Chicago generates sizable changes in policing outcomes. Third, as part of that management intervention the department adopted a predictive policing tool that randomizes which high-crime areas it shows to officers. We use that randomization to generate district-specific measures of implementation fidelity and show that, even within the context of a management intervention designed to improve implementation of the department’s strategies, there is variability in implementation.

Cambridge, MA: National Bureau of Economic Research, 2022. 104p.

By David Bjerk

This paper examines the impact of police funding on the fraction of homicides that are cleared by arrest. Using data covering homicides in approximately 50 of the largest US cities from 2007 to 2017, I find no evidence that greater police funding resulted in higher homicide clearance rates. This finding is robust to linear regression and instrumental variable approaches, different ways to measure police budgets, and across victims of different races and in different types of neighborhoods. In summary, the way large city police departments have historically spent their funds, more funding has not helped catch more murderers.

Journal of Empirical Legal Studies, 2022; 19: 528-559

By Rashida Richardson, Jason M. Schultz, and Kate Crawford

Law enforcement agencies are increasingly using predictive policing systems to forecast criminal activity and allocate police resources. Yet in numerous jurisdictions, these systems are built on data produced during documented periods of flawed, racially biased, and sometimes unlawful practices and policies (“dirty policing”). These policing practices and policies shape the environment and the methodology by which data is created, which raises the risk of creating inaccurate, skewed, or systematically biased data (“dirty data”). If predictive policing systems are informed by such data, they cannot escape the legacies of the unlawful or biased policing practices that they are built on. Nor do current claims by predictive policing vendors provide sufficient assurances that their systems adequately mitigate or segregate this data.

In our research, we analyze thirteen jurisdictions that have used or developed predictive policing tools while under government commission investigations or federal court monitored settlements, consent decrees, or memoranda of agreement stemming from corrupt, racially biased, or otherwise illegal policing practices. In particular, we examine the link between unlawful and biased police practices and the data available to train or implement these systems. We highlight three case studies: (1) Chicago, an example of where dirty data was ingested directly into the city’s predictive system; (2) New Orleans, an example where the extensive evidence of dirty policing practices and recent litigation suggests an extremely high risk that dirty data was or could be used in predictive policing; and (3) Maricopa County, where despite extensive evidence of dirty policing practices, a lack of public transparency about the details of various predictive policing systems restricts a proper assessment of the risks. The implications of these findings have widespread ramifications for predictive policing writ large. Deploying predictive policing systems in jurisdictions with extensive histories of unlawful police practices presents elevated risks that dirty data will lead to flawed or unlawful predictions, which in turn risk perpetuating additional harm via feedback loops throughout the criminal justice system. The use of predictive policing must be treated with high levels of caution and mechanisms for the public to know, assess, and reject such systems are imperative.

94 N.Y.U. L. REV. ONLINE 192 (2019), Available at SSRN: https://ssrn.com/abstract=3333423

By Aaron Chalfin, Benjamin Hansen, Emily K. Weisburst & Morgan C. Williams, Jr.

We report the first empirical estimate of the race-specific effects of larger police forces in the United States. Each additional police officer abates approximately 0.1 homicides. In per capita terms, effects are twice as large for Black versus white victims. At the same time, larger police forces make more arrests for low-level “quality-of-life” offenses, with effects that imply a disproportionate burden for Black Americans. Notably, cities with large Black populations do not share equally in the benefits of investments in police manpower. Our results provide novel empirical support for the popular narrative that Black communities are simultaneously over and under-policed. 

 American Economic Review: Insights, American Economic Association, vol. 4(2), pages 139-158, June.

By Stephen Wu

Objective.This study analyzes the relationship between the race of a city’s police chief and the incidence of fatal shootings by police officers.Methods.The Washington Post’s “Fatal ForceDatabase” is used to calculate per-capita rates of fatal shootings by police officers occurring between January 1, 2015 and June 1, 2020 for the 100 largest cities in the United States. I compare fatal shooting rates for cities with police chiefs of different races, both unadjusted and adjusted for differences in city characteristics.Results.Rates of fatal shootings by officers are almost 50 percenthigher in cities with police forces led by white police chiefs than in cities with black police chiefs.Of the 30 cities with the highest rates of fatal shootings, 23 have police departments led by whites and only four have departments led by blacks, while of the 30 cities with the lowest rates, 16 have police departments led by blacks and only 11 are led by whites. Differences in fatal shooting rates persist after controlling for city characteristics.Conclusion.Leaders in the highest position of au-thority may have a powerful effect on the culture of a police department and its resulting behavior.Each year, there are approximately 1,000 fatal shootings by police officers across theUnited States, a statistic that has been fairly steady over the course of the last several years.With recent efforts to track and compile more comprehensive data, researchers have been increasingly studying the factors that contribute to these deaths. Prior research has looked at many factors surrounding fatal officer-involved shootings, including racial and demo-graphic information of both officers and victims, situational and location characteristics,and structural and organizational factors. This study contributes to the literature by look-ing at one as of yet unstudied factor: the race of a city’s police chief.Much of the prior work on police shootings has focused on the demographics of vic-tims. Edwards, Lee, and Esposito (2019) show that age and race are significant factors in determining the risk of being killed by police. Specifically, individuals between the ages of20 and 35 have the highest risk of all different age groups. They also find that blacks, Latinos, and Native Americans are significantly more likely to be killed by police than whites. An important distinction between sheriffs and police chiefs (or commanders, commissioners, captains,and superintendents) is that sheriffs are directly elected, while other top leaders are appointed by the mayor or city council. Sheriff’s departments also may have additional duties for their jurisdictions including supervision of correctional facilities and providing court security. There are only two cities in the data with elected sheriffs,and the analysis is not affected by eliminating these two departments.

SOCIAL SCIENCE QUARTERLY, Volume 102, Number 1, January 2021

By Luke Bonkiewicz

The author of this report notes that recruitment and retention are critical issues in law enforcement, and that in order to address those issues, many agencies consider implementing a type of flexible scheduling called job sharing, in which two people share the duties of a single position while dividing the benefits. The author suggests that law enforcement agencies that are unable to implement job sharing may be able to utilize other flexible scheduling arrangements such as part-time positions or extended leave for qualifying events. The author identifies potential benefits of job sharing, including the retention of two people on one salary, improves employee work-life balance, reduces stress and burnout, supports greater productivity, and more. Potential drawbacks discussed by the author include training and equipping two people for one position, more employees to supervise and evaluate, it may require benefit reduction for job sharers, and it may not be allowed by local union contracts or local laws. The author makes several recommendations for the implementation of job sharing programs, including to conduct a focus group or survey to gauge interest in such a program, to identify and evaluate state legislation and local ordinances that may affect the implementation of job sharing, evaluate which units may benefit from a job sharing program and develop specific policies for those units and the specific positions, train employees and supervisors on the topic, and once a program has been implemented, to conduct ongoing evaluations. Alternative options to job sharing may include other types of flexible scheduling, such as the expansion of part-time officers and assignments, working from home, or extended leave policies. The author suggests that proper implementation can improve both recruitment and retention for police agencies as well as prolong officers’ careers and alleviate staffing shortages.

Washington, DC: U.S. Bureau of Justice Assistance, 2023. 21p.