To learn about any of CEBCP’s past and present policing projects, please click on the links below.

Community Policing and Crime Inflation: A Preliminary Study

David Weisburd (PI), Charlotte Gill (Co-PI), and David Wilson (Co-PI). Funded by Arnold Ventures.

The project seeks to critically examine and refine the concept of crime reporting inflation—which seeks to measure the extent to which crime control outcomes for community policing are biased due to the inherent impact of community policing programs on citizen willingness to call the police.

Police Stops, Crime Prevention, and Community Reaction: A Randomized Field Experiment at Violent Crime Hot Spots

David Weisburd (PI), The National Police Foundation; with Taryn Zastrow (Research Assistant). Funded by the National Institute of Justice through the National Police Foundation.

The National Police Foundation and George Mason University are conducting a randomized experiment in Phoenix, Arizona, to test whether an enhanced version of pedestrian stops focused on violent crime hot spots and informed by constitutional and procedural justice principles can significantly affect crime in hot spots while enhancing perceptions of procedural justice among those stopped, and increasing community opinions about police legitimacy.

Preventing, preparing, and responding to COVID-19: An in-depth case study on the impacts of COVID-19 on the Fairfax County Police Department

Cynthia Lum (PI) and Christopher Koper (PI); with Michael Goodier, Heather Prince, Bill Johnson, and Xiaoyun Wu (Research Assistants). Funded by the Bureau of Justice Assistance through the Fairfax County Police Department.

CEBCP researchers conducted an in-depth case study of the impacts of COVID-19 on the Fairfax County Police Department. This study assesses the impacts of COVID-19 on crimes, disorders, and other public safety concerns; on patrol and investigative operations as well as human resources; and on police-community interactions. The goal of this case study will be to describe the agency’s response and document ideas and lessons learned for a national audience. The final report is now available:

Lum, C., Koper, C.S., Wu, H.X., Goodier, M., Johnson, W., Shadur, J., & Krause, J. (2022). The Impact of COVID-19 on Policing: A Case Study of the Fairfax County Police Department. Fairfax, VA: Center for Evidence-Based Crime Policy, George Mason University.

Translating, Communicating, and Institutionalizing Research into Policing Practice: A Collaboration between the Prince William County Police Department and the Center for Evidence-Based Crime Policy (ongoing).

Cynthia Lum (PI) and Christopher Koper (PI); with Xiaoyun Wu and Michael Goodier (Research Assistants). Funded by the National Academies of Sciences.

Evidence-based policing advocates for not only generating research knowledge about effective and fair police practices, but also translating, communicating, and institutionalizing science and research into police operations. This requires both dissemination strategies as well as the reengineering of police organizational infrastructures, policies, and practices to create environments that are more receptive to research use. However, while a great deal of rigorous, scientific research has been generated about policing, the actual use of that knowledge has been limited. Improving this situation requires researchers to collaborate with practitioners in the field to help them understand and implement evidence-based practices and to create viable operational examples that others can use to facilitate further transmission and institutionalization of research. Toward this end, this project partners police researchers and practitioners to explore various translation tools for implementing evidence-based policing in the field and examine the translation mechanisms those practitioners use to encourage adoption of these practices by others in their agency.

The Iowa State Patrol Fatality Reduction Enforcement Effort (FREE) (completed).

Christopher Koper (PI), Cynthia Lum (CoPI), and Ken Clary (Practitioner Lead); with Xiaoyun Wu and Michael Goodier (Research Assistants). Funded by the International Association of Directors of Law Enforcement Standards and Training/National Highway Transportation Safety Administration.

This project involves the participation in, and evaluation of, the Fatality Reduction Enforcement Effort (FREE), an innovative, evidence-based program implemented by the Iowa State Patrol (ISP, Captain Ken Clary) to reduce vehicular crashes in a rural section of Iowa encompassing 28 counties, 16,000 square miles, and a population of roughly 650,000. The FREE program was designed specifically for use in rural areas, which have higher risks for serious crashes and account for 80% of vehicle fatalities in Iowa.1 Based on a problem-solving framework, the program concentrates on changing driving behaviors and routines at hot spot road segments for crashes and activity hot spots that serve as likely origin points for drivers involved in crashes. Officers conduct intermittent, high-visibility patrols in these locations, complemented with preventive community contacts stressing safety messages at locations such as bars, gas stations, and convenience stores. These activities are intended to promote deterrence, community engagement, and police legitimacy while also addressing the broader opportunity structures that contribute to vehicle crashes. FREE was implemented as a pilot program in 2018 and expanded to an entire ISP command in 2019.

Koper, C.S., Lum, C., Wu, X., Goodier, M., & Clary, K. (2021). The Iowa State Patrol Fatality Reduction Enforcement Effort (FREE). Evaluation Report for the National Highway Transportation Safety Administration (NHTSA) and the International Association of Law Enforcement Standards and Training (IADLEST). Fairfax, VA: Center for Evidence-Based Crime Policy, George Mason University.

An Evidence-Assessment of the Impacts of Criminal Investigations on Crime Clearance (completed).

Cynthia Lum (PI), Christopher Koper (PI); with Heather Prince (Research Assistant). Funded by Arnold Ventures.

Detective work is a mainstay of modern law enforcement, but its effectiveness has been much less evaluated than patrol work. To explore what is known about effective investigative practices and to identify evidence gaps, this project assesses the current state of empirical research on investigations and coordinates a workshop of the leading investigations researchers to identify research gaps for future funding. The evidence assessment discovered 80 studies that focus on seven categories of investigations research, which include the impact that case and situational factors, demographic and neighborhood dynamics, organizational policies and practices, investigative effort, technology, patrol officers and community members have on case resolution. The assessment indicated that evaluation research examining the effectiveness of various investigative activities is rare. However, the broader empirical literature indicates that a combination of organizational policies, investigative effort and certain technologies can be promising in improving investigative outcomes even in cases deemed less solvable. From an evidence-based perspective, this review emphasizes the need for greater transparency, evaluation and accountability of investigative activities given the resources and importance afforded to criminal investigations. The workshop confirmed these findings and more specifically highlighted research needs.

Prince, H., Lum, C., & Koper, C.S. (2021). Effective police investigative practices: An evidence-assessment of the research. Policing: An International Journal (of Strategies and Management), 44(4), 683-707.

Lum, C., Koper, C.S., & Prince, H. (2021). Building Evidence for Effective Investigations: A Collaborative Workshop to Identify Research Needs. Workshop summary to Arnold Ventures. Fairfax, VA: Center for Evidence-Based Crime Policy, George Mason University.

Improving the Investigation, Clearance Rates, and Victim Restoration of Robberies: A Randomized Controlled Experiment

Cynthia Lum (PI) and Christopher Koper (PI); with Xiaoyun Wu, Michael Goodier, William Johnson, and Heather Prince (Research Assistants). Funded by the National Institute of Justice.

One of the most important purposes for law enforcement is the investigation and resolution of crime, functions to which agencies devote significant resources. Yet, there has been a longstanding belief amongst some law enforcement officials and researchers that crime clearance rates are out of the hands of the police and are instead the result of the circumstances of the crimes. These beliefs have prompted many police agencies to triage crimes by their solvability factors to allocate scarce investigative resources to crimes that most likely can be solved. However, these beliefs and practices have been challenged by recent studies showing that enhanced investigative efforts can improve clearance rates. The practice of triaging cases for solvability may thus be premature, as serious crimes can potentially be solved (and thus their victims redeemed) if given some investigative effort. The study builds on this research evidence and tests an investigative intervention to increase the clearance rate and victim satisfaction for robberies using a randomized controlled experiment.

The Patrol Time Study

Cynthia Lum (PI) and Christopher Koper (PI); with Xiaoyun Wu, Michael Goodier, Megan Stoltz, William Johnson, and Heather Prince (Research Assistants). Funded by the Laura and John Arnold Foundation.

In The Proactivity Lab (below, also supported by Arnold Ventures), we focused on how police officers spend their time when not answering calls for service, and how they strategize their efforts during this time for crime prevention goals. In this project, we examine the flip side of that deployment coin: the public’s call for police services and the police response. How patrol officers spend their day is partially determined by the public’s calls for their service. Learning about the origins of these calls, how they are processed through public safety communications centers, how they are ultimately dispatched, and how much time officers spend on them, are essential elements to understanding patrol deployment and how law enforcement resources are expended.

Lum, C., Koper, C. S., & Wu, X. (2021). Can we really defund the police? A nine-agency study of police response to calls for service. Police Quarterly.

Lum, C., Koper, C.S., Stoltz, M., Goodier, M., Johnson, W., Prince, H., & Wu, X. (2020). Constrained gatekeepers of the criminal justice footprint: A systematic social observation study of 9-1-1 calltakers and dispatchers. Justice Quarterly, 37(7), 1176-1198.

The Proactive Policing Lab

Cynthia Lum (PI) and Christopher Koper (PI); with Xiaoyun Wu, William Johnson, Megan Stoltz, and Sang Jun Park (Research Assistants). Funded by the Laura and John Arnold Foundation.

One of the most significant reforms in modern policing has been the push for police to be more proactive, either to reduce crime or to build trust and confidence with citizens. While there have been controversies surrounding certain types of proactivity such as stop-question-and-frisk, pretextual traffic stops, and zero tolerance policing, research continues to find that many other types of proactive approaches (e.g., problem-solving, positive community contacts, and patrol visibility) can be effective in not only preventing crime and disorder but improving citizen satisfaction with the police. However, despite studies evaluating specific proactive interventions, we actually know little about the realities of proactive policing, including the extent to which police officers and agencies in the U.S. are proactive, the types, frequency and dosages of proactivity by officers, and the impacts and consequences of police proactivity. The Proactive Policing Lab was established by professors Lum and Koper within the Center for Evidence-Based Crime Policy at George Mason University to examine these questions.

Koper, C.S., Lum, C., Wu, X., & Fritz, N. (2020). Proactive policing in the United States: A National Survey. Policing: An International Journal (of Strategies and Management), 43(5), 861-876.

Lum, C., Koper, C.S., Wu, X., Johnson, W.D., & Stoltz, M. (2020). Examining the empirical realities of proactive policing through systematic observations and computer-aided dispatch data. Police Quarterly, 23(3), 283-310.

Lum, C., Koper, C.S., Johnson, W.D., Stoltz, M., Wu, X., & Carr, J. (2017). Measuring Police Proactivity. The Police Chief, August 2017, 16-17.

Wu, X., & Lum, C. (2019). The practice of proactive traffic stops. Policing: An International Journal of Police Strategies and Management, 43(2), 229-246.

Koper, C.S., Lum, C., Wu, X., & Hegarty, T. (2021). The long-term and system-level impacts of institutionalizing hot spot policing in a small city. Policing: A Journal of Policy and Practice, 15(2), 1110-1128.

Wu, X., Lum, C., & Koper, C.S. (2021). Do everyday proactive policing activities reduce vehicle crashes? Examining a commonly held law enforcement belief using a novel method. Journal of Criminal Justice, 76,101846.

Koper, C.S., Wu, X., & Lum, C. (2021). Calibrating police activity across hot spot and non-hot spot areas. Police Quarterly, 24(3), 382-406.

Wu, X., Koper, C.S., & Lum, C. (2021). Measuring the impacts of everyday police proactive activities: Tackling the endogeneity problem. Journal of Quantitative Criminology

Basic Analysis of Traffic Citation Data for the Alexandria Police Department 2011-2015

Cynthia Lum and Xiaoyun Wu

At the request of the Alexandria City (VA) Police Department, we conducted an independent and preliminary analysis of the police department’s traffic citation data from 2011-2015.

REPORT: Basic Analysis of Traffic Citation Data for the Alexandria Police Department 2011-2015 (by C. Lum and X. Wu)

An Evidence-Assessment of the Recommendations of the President’s Task Force on 21st Century Policing

Cynthia Lum (PI), Christopher Koper (PI), Charlotte Gill (CoPI), Cody Telep, Julie Hibdon, and Laurie Robinson (Faculty Researchers) (Laura and John Arnold Foundation)

The Final Report of the President’s Task Force on 21st Century Policing is one of the most significant documents for law enforcement in modern history. The Task Force was charged by President Obama in 2014 to “examine ways of fostering strong, collaborative relationships between local law enforcement and the communities they protect and to make recommendations to the President on the ways policing practices can promote effective crime reduction while building public trust” (Final Report, p. 5). But where should law enforcement agencies begin in implementing these recommendations? Which recommendations should be prioritized for action, for policy implementation, or for more research? With a grant from the Laura and John Arnold Foundation, the Institute for Community-Police Relations of the International Association of Chiefs of Police (IACP) has collaborated with researchers from George Mason University’s (GMU) Center for Evidence-Based Crime Policy to create an evidence-based Blueprint for 21st Century Policing. The research team was charged with reviewing existing research knowledge about those Task Force recommendations relevant to state and local law enforcement, highlighting promising efforts based on research knowledge, and identifying issues that need more research and testing.

REPORT: An Evidence-Assessment of the Recommendations of the President’s Task Force on 21st Century Policing (by C. Lum, C.S. Koper, C. Gill, J. Hibdon, C. Telep, and L. Robinson)

Body Worn Cameras: Knowledge Gaps and Opportunities

Cynthia Lum (PI), Christopher Koper (PI), Linda Merola (Faculty Researcher), Amber Scherer and Amanda Reioux (Research Assistants) (Laura and John Arnold Foundation)

Recent use-of-force events have led law enforcement agencies, citizens, civil rights groups, city councils, and even the President to push for the rapid adoption of body-worn camera (BWC) technology. In a period of less than a year, BWCs transformed from a technology that received little attention by many police leaders and scholars to one that has become rapidly prioritized, funded, and diffused into local policing. At the same time, this rapid adoption of BWCs is occurring within a low information environment; researchers are only beginning to develop knowledge about the effects, both intentional and unintentional, of this technology. Much more research is needed to understand the intended and unintended impacts and consequences of cameras. In this project, we identify knowledge gaps and opportunities for research on body worn cameras, examine concerns in law enforcement and the courts regarding body worn cameras, and assist in making evidence-informed decisions about this technology. To access all completed reports, go to the Body Worn Camera webpage in our Technology Webportal.

Identifying effective investigative practices: A National Study Using Trajectory Analysis

Cynthia Lum (PI), Charles Wellford (PI), Thomas Scott and Heather Vovak (Laura and John Arnold Foundation)

Most serious violent and property crimes do not result in clearance, and clearance rates for these crime categories have not changed in over thirty years; indeed, for homicide, clearance rates have declined dramatically. Current research on crime clearances leaves many questions unanswered including what police can do to improve clearance rates in a just and respectful manner. Our preliminary examination of UCR data in the last three decades shows that despite significant fluctuations in crime rates, some agencies have maintained high clearance rates for all serious crimes during this period while others have shown a pattern of low clearance or even consistent declines. This study will analyze and understand this variation using trajectory approaches (Nagin), and further identify a sample of agencies that differ in clearance trajectories to explore why some agencies perform better than others.

Phase I Report: Trajectories of U.S. Crime Clearance Rates (by C. Lum, C. Wellford, T. Scott, and H. Vovak).

Final Report: Identifying Effective Investigative Practices: A National Study Using Trajectory Analysis, Case Studies, and Investigative Data. (by C. Lum, C. Wellford, T. Scott, H. Vovak, & J.A. Scherer).

Evaluating the Crime Control and Cost-Benefit Effectiveness of License Plate Recognition (LPR) Technology

Cynthia Lum (PI), Christopher Koper (PI), James Willis (CoPI), Stephen Happeny, Heather Vovak, and Jordan Nichols (NIJ: 2013-IJ-CX-0017)

This study examines the crime control and cost-effectiveness of the use of license plate readers (LPR) in police agencies. Preliminary assessments of LPR focused on the efficiency of the technology itself, not its crime control or cost-effectiveness. Limited randomized experiments conducted by this study’s PIs in northern Virginia and Mesa, AZ (discussed below) have provided mixed evidence on LPR’s effectiveness in reducing crime and suggest that the impact of LPR use on crime may depend on the scale of LPR deployment, the information and information sharing supporting LPR systems, and the specific ways that LPRs are used. In this study, we explored the effectiveness of LPR in both investigations and patrol, as well as conduct a national survey to assess the diffusion of this innovation.

Koper, C.S., Lum, C., Wu, X. et al. (2021). Do license plate readers enhance the initial and residual deterrent effects of police patrol? A quasi-randomized test. Journal of Experimental Criminology.

Lum, C., Koper, C.S., Willis, J., Happeny, S., Vovak, H. and Nichols, J. (2019). The rapid diffusion of license plate readers in US law enforcement agencies. Policing: An International Journal, 42(3), 376-393.

Koper, C. S., & Lum, C. (2019). The Impacts of Large-Scale License Plate Reader Deployment on Criminal Investigations. Police Quarterly, 22(3), 305–329.

Willis, J.J., Koper, C.S., & Lum, C. (2018). The Adaptation of License-plate Readers for Investigative Purposes: Police Technology and Innovation Re-invention. Justice Quarterly, 35(4), 614-638.


Cynthia Lum (PI), Christopher Koper (PI), Cody TelepJulie Hibdon, Julie Grieco,  Heather Vovak, Xiaoyun Wu (BJA: 2011-DB-BX-K012)

The Evidence-Based Policing Matrix is a research-to-practice translation tool that categories and visualizes all experimental and quasi-experimental research on police and crime reduction according to three common dimensions of crime prevention – the nature of the target, the extent to which the strategy is proactive or reactive, and the specificity or generality of the strategy. This categorization and visualization of policing evaluation studies reveals three-dimensional clusters of effective studies, which we refer to as “realms of effectiveness.” These realms of effectiveness provide insights into the nature and commonalities of effective police strategies and can be used by police agencies to guide various aspects of their operations.

Learn more about the Matrix Demonstration Project and related publications, videos, training sessions, and guidebooks here.

Improving Police Response to Mental Health Crisis in a Rural Area

Sue-Ming Yang (PI), Charlotte Gill (co-PI), Caitlin Kanewske, Paige St. Clair Thompson

Bureau of Justice Assistance Smart Policing Initiative (with Roanoke County Police Department), 2015-WY-BX-0007, $630,000

Mental health-related calls are a major concern in Roanoke County, as in many police departments around the country. While they account for a small number of calls overall, they disproportionately consume police and mental health service resources. This is especially challenging in a rural department like Roanoke, where services are already limited. CEBCP and RCPD are collaborating to transform RCPD’s current approach to these calls by providing quality mental health service to people with mental illness who have contact with the police. CEBCP and RCPD have partnered with Intercept Youth Service’s Crisis One program to design and implement a standard treatment response. Police will have 24-hour access to on-call trained mental health professionals, who can take over from officers where a mental health issue is identified but the individual does not meet the criteria for arrest or emergency custody. We are evaluating the results of the program in a randomized controlled trial.

See our project page on the Smart Policing Initiative website for more information.

See also:

Charlotte Gill (PI) and Rachel Jensen, with Heather Vovak (co-PI, National Police Foundation)

Bureau of Justice Assistance Smart Policing Initiative (with Shoreline Police Department), 2015-WY-BX-0005, $630,000

CEBCP, the Police Foundation, and Shoreline Police Department are collaborating to develop RADAR, a community-focused program that seeks to reduce repeat calls for service and the risk of use-of-force incidents between police and individuals with mental or behavioral health issues and/or developmental disabilities (BH/DD). The RADAR approach involves relationship building between police and individuals with BH/DD and information sharing among first responders to improve emergency response when the individual is in crisis. The goals of the program include developing individualized de-escalation strategies, connecting individuals with BH/DD to existing services and treatment, and promoting police-community collaboration. RADAR will be evaluated using a rigorous quasi-experimental evaluation.

See our project page on the Smart Policing Initiative website for more information.

FINAL REPORT: C. Gill, R. Jensen, and H. Vovak (2019). RADAR: Response Awareness, De-Escalation, and Referral. Final evaluation report. Center for Evidence-Based Crime Policy, Department of Criminology, Law & Society, George Mason University.

See also:

Gill, C., Jensen, R., & Cave, B. (2018). Exploring physical force and subject resistance in police encounters with people with behavioral health issues. Victims & Offenders13(8), 1106–1131.

Implementing and Evaluating Community Policing in Hot Spots of Juvenile Offending

David Weisburd (PI), Charlotte Gill (co-PI), and Zoe Vitter

Office of Community Oriented Policing Services, 2012-CK-WX-K026, $250,000

While there is a growing body of research indicating that crime concentrates at small geographic units or ‘hot spots,’ little research has examined the unique characteristics of juvenile offending at places. In this project, funded by the Office of Community Oriented Policing Services, we developed, implemented, and rigorously evaluated a community-oriented policing approach to juvenile crime hot spots in Seattle. The police worked with the community to develop community policing and problem-solving responses targeted at the specific risk factors for juvenile crime in each hot spot. These strategies, while police-led, focused on crime prevention rather than traditional arrest-based law enforcement approaches. Although the police achieved several successes, there was no overall effect on crime in the hot spots. However, the project revealed key lessons for police leaders and jurisdictions seeking to implement community policing, including the importance of organizational support and training for community policing efforts.

FINAL REPORT: C. Gill, D. Weisburd, Z. Vitter, C. Gross Shader, T. Nelson-Zagar, and L. Spain. (2018). When Innovation is Not Enough: Implementing and Evaluating Community Policing in Hot Spots of Juvenile Offending. Fairfax, VA: Center for Evidence-Based Crime Policy, George Mason University.

See also:

C. Gill, Z. Vitter, and D. Weisburd. (2015). Identifying Hot Spots of Juvenile Offending: A Guide for Crime Analysts. Washington, DC: U.S. Department of Justice, Office of Community Oriented Policing Services.

C. Gill, D. Weisburd, Z. Vitter, C. Gross Shader, T. Nelson-Zagar, and L. Spain. (2016). When is Innovation Not Enough? The Importance of Organizational Context in Community PolicingTranslational Criminology, 11 (Fall 2016). George Mason University, Center for Evidence-Based Crime Policy.

Increasing Collective Efficacy at Crime Hot Spots: A Patrol Force Approach in Brooklyn Park, Minnesota

David Weisburd (PI), Charlotte Gill (co-PI),  Alese Wooditch, and Tori Goldberg

Bureau of Justice Assistance Smart Policing Initiative (with Brooklyn Park Police Department), 2013-DB-BX-0030, $700,000

This project capitalizes on new evidence that indicators of social control, such as collective efficacy, are concentrated at individual street blocks. High collective efficacy is associated with a lower risk of a block becoming a crime hot spot. Traditional hot spots policing approaches rarely account for the social context of crime at places, or the role of the community in crime prevention. In this project, CEBCP and the Brooklyn Park Police Department collaborated to develop a problem-solving approach called ACT (Assets Coming Together to Take Action), in which police first identified “assets” (key residents and community resources) at the hot spots and then brought these resources together to collectively develop solutions to crime problems. The goal of ACT is for the police to help encourage collective action and collective efficacy among residents in crime hot spots, as well as reducing crime and improving perceptions of police legitimacy and safety. We evaluated ACT using a block-randomized controlled trial in 42 hot spots. We found that the intervention increased collective action at hot spots but had little impact on collective efficacy or police legitimacy. Crime reporting was inflated in the treatment sites. There was a statistically significant reduction in crime in the treatment areas when we adjusted for this reporting inflation. Our experimental findings show that collective actions at hot spots can be encouraged through programs like ACT using ordinary policing resources. At the same time, there may be a bias in using official crime data to assess outcomes in programs that encourage community collaboration.

FINAL REPORT: D Weisburd, C. Gill, A. Wooditch, W. Barritt, and J. Murphy. (2018). Assets Coming Together (ACT) at Crime Hot Spots: An Experimental Evaluation in Brooklyn Park, Minnesota. Fairfax, VA: Center for Evidence-Based Crime Policy, George Mason University.

See also:

Weisburd, D., M. Davis, and C. Gill (2015). Increasing Collective Efficacy and Social Capital at Crime Hot Spots: New Crime Control Tools for Police. Policing: A Journal of Policy and Practice, 9(3), 265-274.

Gill, C., Wooditch, A., & Weisburd, D. (2017). Testing the “law of crime concentration at place” in a suburban setting: Implications for research and practice. Journal of Quantitative Criminology33(3), 519–545.

Process Evaluation of the Seattle Youth Violence Prevention Initiative’s School Emphasis Officer Program

Charlotte Gill (PI) and Kirsten Hutzell with Denise Gottfredson (University of Maryland)

City of Seattle Office of City Auditor, $100,000

Seattle’s City Auditor finds that Seattle Police Department has been “thoughtful in the development” of its School Emphasis Officer (school police) program, seeking to avoid the focus on patrol and enforcement that characterizes some police activity in schools. The program’s website states that the SEOs are “specially selected for their interest and experience in working with youth,” and focus on providing support to at-risk youth through promising approaches such as mentoring and conflict resolution/restorative justice, home visits, and referral to services. However, as with most school police programs, Seattle’s approach has not been evaluated. In this process evaluation we documented the SEO program through analysis of program documentation; interviews with key stakeholders, including the SEOs themselves; and observations of the SEOs working in the schools. We found that the program was implemented in line with a non-law enforcement focus and had good potential for integration with services and enhancement of police-community relations. However, it also faced important challenges, including clarity of the program structure; evaluability; and sustainability. We provided recommendations for clarifying the program with a view toward future rigorous evaluation.


See also:

Gill, C., D. Gottfredson, and K. Hutzell (2016). Can School Policing be Trauma-Informed? Lessons from SeattlePolicing: An International Journal of Police Strategies and Management, 39(3), 551-565.

Realizing the Potential of Technology In Policing: A Multisite Study of the Social, Organizational, and Behavioral Aspects of Implementing Policing Technologies. National Institute of Justice Office of Research and Evaluation

Christopher Koper (PI), Cynthia Lum (PI), James Willis (co-PI), and Julie Hibdon, in collaboration with the Police Executive Research Forum. (NIJ: 2010-MU-MU-0019)

This project examines the social, organizational, and behavioral implications of some of the most commonly used technologies in policing.  While technological advances hold great promise for enhancing the effectiveness, fairness, and legitimacy of policing, there has been little research on the implementation and impacts of policing technology, and that which does exist suggests that technology does not always bring expected benefits. There is thus a need to better understand both how technology affects police agencies and how, in turn, various aspects of police agencies and their environments shape the uses and effectiveness of policing technology. This project examined these issues through in-depth cases studies and experiments in four police agencies. Findings from this project can help illuminate the organizational practices and changes needed to fully realize the potential of technology for enhancing the fairness and effectiveness of policing.

Final Report

See also:

Koper, C.S., C. Lum, and J. Willis (2014). Optimizing the Use of Technology in Policing: Results and Implications from a Multi-Site Study of the Social, Organizational, and Behavioral Aspects of Implementing Police Technologies. Policing: A Journal of Policy and Practice, 8(2), 212-221.

Lum, C. “The Impact of Technology on Modern Policing” Podcast lecture in receipt of the James Smart Memorial Medal.

Smartphone Deployment and Custom App Development for Policing (completed)

David Weisburd (PI), Charlotte Gill (co-PI), in collaboration with Redlands Police Department (Travis Taniguchi, PI)

National Institute of Justice, 2010-DE-BX-K006, $475,000

Advances in technology, such as smartphones and other mobile devices, provide new opportunities for data-driven law enforcement. CEBCP collaborated with the Redlands, CA Police Department (RPD) and the Omega Group to develop and test an iPhone application that allows police officers to access and record data on hot spots, crime incidents, and people while out on patrol. The research team surveyed officers and civilians within the department to understand their technological capabilities and needs, and evaluated the prototype app in a randomized controlled field experiment.


See also:

Taniguchi, T. A., & Gill, C. (2019). The mobilization of computerized crime mapping: A randomized controlled trial. Journal of Experimental Criminology15(2), 213–225.

Evidence-Assessment for the Federal Protective Service

Cynthia Lum (PI), Breanne Cave and Jordan Nichols

In this project CEBCP conducted an evidence assessment of the Interagency Security Committee’s security criteria and building security determinations for the Federal Protective Service.


Evaluation of the Transportation Security Administration’s Comprehensive Strategy to Security at Airports

David Weisburd (PI), Cynthia Lum (PI), Charlotte Gill, Devon Johnson, Linda Merola, Julie Willis Hibdon, Heather Vovak, Jordan Nichols, Jaspreet Chahal and Breanne Cave (DHS: 2010-ST-108-LR005)

The security of transportation facilities is of national concern and carries significant costs. Yet, very little evidence exists on what types or processes, programs, and interagency strategies yield the most effective cost-beneficial security structures. Through funding from the Department of Homeland Security, this project examines crime prevention and security in our nation’s airports in a multi-stage evaluation.

Phase I Report (Evidence-assessment of the Playbook, redacted version)

Phase IIa Report (National Survey of Category X, I, and II Airports, redacted version)


Phase III Report (Playbook implementation at ten U.S. Airports) NOT YET AVAILABLE FOR PUBLIC DISSEMINATION

See also: Lum, C., C. Gill, B. Cave, J. Hibdon and D. Weisburd. (2011). Translational Criminology: Using existing Evidence for Assessing TSA’s Comprehensive Security Strategy at U.S. Airports. For C. Lum and L. Kennedy (Eds.), Evidence-Based Counterterrorism PolicyNew York, NY: Springer-Verlag.

City of Seattle Project

David Weisburd, Cynthia Lum, and Charlotte Gill

On May 2 and 3, 2011, the City of Seattle and the CEBCP collaborated on a series of discussions about evidence-based approaches to crime reduction. Click here to see the presentations, notes, and related links from the discussions. Seattle’s Office of City Auditor also issued a report “Addressing Crime and Disorder in Seattle’s “Hot Spots”: What Works?” based in part on research by David Weisburd and colleagues on crime at place in Seattle.

In September 2012 The Seattle Office of City Auditor published the Review of Research Literature done by CEBCP as part of the Evidence-Based Assessment of the City of Seattle’s Crime Prevention Programs.

Sacramento Police Department Partnership

Renee Mitchell, Sacramento PD (PI), David Weisburd, Cynthia Lum, Christopher Koper and Cody Telep

Sgt. Renee Mitchell in collaboration with the CEBCP has recently completed a hot spots policing experiment in Sacramento. Sgt. Mitchell undertook this project without any additional funding. The Sacramento Police Department released a press release announcing the significant crime declines that resulted from the experiment: “‘Hot Spots’ Policing Reduces Crime” and the COPS Office also summarized the results from the experiment.

See also Telep, C., Mitchell, R. and Weisburd, D. (2012). How Much Time Should the Police Spend at Crime Hot Spots? Answers from a Police Agency Directed Randomized Field Trial in Sacramento, California. Justice Quarterly. DOI: 10.1080/07418825.2012.710645. 

Cynthia Lum (PI) and Linda Merola (co-PI)with Julie Willis Hibdon and Breanne Cave

Objectives: This randomized controlled experiment tests whether license plate readers (LPR) deter crime generally, and automobile crime more specifically in crime hot spots. The limited intervention tested here reflects one current likely use of LPR at the time of this publication.

Methods: We use a place-based block randomized experiment. Our subjects were 30 hot spots across two jurisdictions, 15 which were assigned to experimental conditions. The treatment involved targeted police patrols using a “sweep and sit” approach with license plate readers in these hot spots, also applying the Koper Curve timing principle. We examine effects of the intervention during and in a 30-day period post-intervention, controlling for pre-intervention levels of crime, seasonal factors, and jurisdiction.

Results: Our findings indicate that, when small numbers of LPR patrols are used in crime hot spots in the way we have tested them here, they do not seem to generate either a general or offense-specific deterrent effect.

Conclusions: While we did not find significant findings of this intervention, a number of limitations and caveats to this study must be considered in conjunction with these findings. The authors suggest how already acquired LPRs might be used in ways that might increase their effectiveness in crime hot spots.

View the full final report to NIJ here. For more information and articles on license plate readers and the articles from this study, go to:

CEBCP-University of Cambridge Partnership

Cynthia Lum (PI)

Building an evidence-based policing infrastructure requires that police researchers understand, develop, and participate in activities that facilitate the translation of research to practice.  One core component of this participation is finding methods to meaningfully interact with police practitioners in ways that convey research findings and provide opportunities to apply research in practice.  The CEBCP-University of Cambridge Partnership pairs the Evidence-Based Research Program with the University of Cambridge, Institute of Criminology, Police Executive Programme (Dr. Lawrence Sherman, Director).  Specifically, this grant serves to build the capacity for law enforcement agents in the United Kingdom to become more evidence-based in their daily practices, to improve their education in this area, and to apply their knowledge acquisition in the field.  This venture is spearheaded by Dr. Cynthia Lum, co-Director of the Evidence-Based Research Program and fellow collaborators of the Evidence-Based Policing Matrix, Drs. Christopher Koper and Cody Telep.

CEBCP-Association of Prosecuting Attorneys Partnership

The field of prosecution needs a stronger evidence-base.  Researchers within the CEBCP explore this need through a collaboration with the Association of Prosecuting Attorneys.  The first project focuses on a research contract on animal abuse. But more generally, the CEBCP and APA hope to begin a relationship in which the area of evidence-based prosecution might be advanced.  Drs. Cynthia Lum and Christopher Koper are developing another Matrix – the “Evidence-Based Prosecution Matrix” in this area.

The San Bernardino Valley Broken Windows Policing Experiment

David Weisburd (PI), Josh Hinkle, Christine Famega, and Justin Ready

Over the last two decades, “Broken Windows Policing” has become a central component of police strategies to combat crime and disorder.  But surprisingly, Broken Windows Policing itself has not been subject to sustained empirical examination.  In this project, we address this knowledge gap by conducting a randomized, experimental evaluation of Broken Windows Policing in three cities in the San Bernardino Valley area of California.  Questions addressed in this study will be whether broken windows policing reduced fear, made residents feel safer, and increased collective community efficacy.  This project is being funded by the National Institute of Justice and is conducted in conjunction with researchers at the University of Maryland and California State University, San Bernardino.

The Effects of Problem-Oriented Policing on Crime and Disorder: A Systematic Review

David Weisburd (PI), Cody Telep, Josh Hinkle, and John Eck

Problem-oriented policing has diffused quickly since Herman Goldstein’s original conception in 1979.  Today, more than two-thirds of large police departments utilize POP.  In this project, we conducted a Campbell Collaboration systematic review of POP programs to synthesize the extant literature on problem-oriented policing to determine whether this widely adopted innovation is effective in reducing crime and disorder.  Eligible studies for this review had to meet rigorous methodological criteria set forth by Campbell .  After an exhaustive literature review, only 10 eligible studies were discovered, which indicate that in general, POP does help reduce crime, but our ability to contextualize this finding was limited by the small number of methodologically rigorous studies.  An examination of pre/post evaluations of problem-oriented policing indicate this program has much promise.

Final report available here.

The Influence of Places on Policing: The NIJ DuBois Fellowship.

Cynthia Lum (PI) (NIJ: 2007-IJ-CX-0032)

Do characteristics of places, in particular their racial, ethnic, immigrant, or language composition, influence police decision making?

As the 2007-2008 National Institute of Justice W.E.B. DuBois Fellow, Dr. Lum examines whether police officers “upgrade” or “downgrade” either the seriousness of a call for service or their decision to take further actions (reports, arrests) may be influenced by the characteristics of people who reside at those places.  Over 250,000 “decision making pathways” for all crime and across all small spaces in an entire city are analyzed in this study.

Article in Justice Quarterly

NIJ Full Report

Cynthia Lum (PI)

Project TIPLINE was developed by Dr. Cynthia Lum at George Mason University, in collaboration with the Departments of Justice (NIJ) and Defense (SPAWAR), to provide law enforcement with free tools to develop tip line systems for building their capacity to respond to critical incidents as well as investigative and community-based problem solving projects using large amounts of publically-garnered information.  Inspired by lessons learned from the Washington DC tri-state area sniper incident, Project TIPLINE is an automated tip collection, management, andanalytic tool which is adaptable, operationally relevant, practitioner friendly, and technologically efficient.  Included with the free software is also an operational handbook designed in consultation with police partners to guide agencies through the process of setting up the automated TIPLINE system and also in developing standard operating procedures, strategies, and tactics for preparing and responding to critical events using large amounts of tips gathered from the public.