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Institute of Criminology



The Jerry Lee Centre for Experimental Criminology at the University of Cambridge Institute of Criminology is a global centre of excellence in the field testing of policies and theories. It conducts and synthesizes highly influential randomized controlled trials of policing, criminal justice and crime prevention programmes, while training a select group of doctoral and post-doctoral students in the methods and practice of experiments in crime and justice. 

The Centre's mission is to produce better evidence about crime and justice for advancing liberty.  Founded in 2007 with support from the Jerry Lee Foundation of Philadelphia, the Jerry Lee Centre has worked in collaboration with police and other agencies in the UK, Australia, US, Denmark and Uruguay. In collaboration with the Australian National University, the Centre has directed the Jerry Lee Program of Randomized Controlled Trials in Restorative Justice, a series of twelve field experiments involving over 3,000 crime victims and offenders.  The Centre is also undertaking new experiments on a variety of innovations for preventing serious crime and anti-social behaviour in high crime hot spots, including a test of stop-and-search deployments with community consent and advanced training in procedural justice. 

Centre Members


Heather Strang


Lawrence Sherman

Chief Analyst

(Professor of Experimental Criminology)

Research Fellows

(Associate Professor in Evidence-Based Policing)


(Associate Professor in Applied Criminology)

Deputy Director

(Assistant Professor in Applied Criminology & Police Management)

PhD Students



News from the Centre

Research News

Recent Publications

  • Bland, A., Ariel, B., and Kumar, S. (2023). Criminal records versus rehabilitation and expungement: a randomized controlled trial. Journal of Experimental Criminology.
  • Alderman, T., Ariel, B., and Harinam, V. (2023). Can a Police-Delivered Intervention Improve Children’ Online Safety? A Cluster Randomised Controlled Trial on the Effect of the “ThinkUKnow” Programme in Primary and Secondary Australian Schools. Journal of Experimental Criminology.
  • Løwenstein, K. M., Harinam, V., and Ariel B. (2023). Targeting Intimate Partner Violence with Police Data: A Study of Offending Patterns in Denmark. European Journal of Crime, Criminal Law and Criminal Justice, 30, 288-309.
  • Løwenstein, K. M., Ariel B., Harinam, V., and Bland, M. (2023). A Simple Metric for Predicting Repeated Intimate Partner Violence Harm Based on the Level of Harm. Policing: An International Journal of Police Strategies & Management. DOI: 10.1108/PIJPSM-03-2022-0046.
  • Hargreaves, M., Harinam, V., and Ariel, B. (2023). Enhancing Recovery Rates for Stolen Vehicles: A Solvability Factors Method. Policing: A Journal of Policy and Practice.
  • Sabo-Brants, H., and Ariel, B. (2023). Building bridges in place of barriers between school practitioners and researchers: on the role of intermediaries in promoting evidence-based violence prevention policy. Evidence & Policy
  • Lay W., Ariel B., and Harinam, V. (2023). Recalibrating the Police to Focus on Victims Using Police Records. Policing: A Journal of Policy and Practice
  • Rothwell, S., McFadzien, K., Strang, H., Hooper, G., & Pughsley, A. (2022) Rapid Video Responses (RVR) vs. Face-to-Face Responses by Police Officers to Domestic Abuse Victims: a Randomised Controlled Trial. Cambridge Journal of Evidence-Based Policing.
  • McKee, J., Ariel, B., and Harinam, V. (2022). Mind the Police Dissatisfaction Gap”: The Effect of Callbacks to Victims of Unsolved Crimes in London. Justice Quarterly.
  • Sherman, L. (2022).  ‘Test-As-You-Go’ for Hot Spot Policing: Continuous Impact Assessment with Repeat Crossover Designs.  Cambridge Journal of Evidence-Based Policing.
  • Clark, B., Ariel, B., and Harinam, V. (2022). How Should the Police Let Victims Down?” The Impact of Reassurance Call-Backs by Local Police Officers to Victims of Vehicle and Cycle Crimes: A Block Randomized Controlled Trial. Police Quarterly.
  • Ross, J., Sebire, J. and Strang, H. (2022).  Tracking Repeat Victims after Domestic Abuse Cases are Heard with and without Independent Domestic Violence Advocates in an English Magistrate’s Court.  Cambridge Journal of Evidence-Based Policing.
  • Harinam, V., Bavcevic, Z. and Ariel B. (2022). Spatial Distribution and Developmental Trajectories of Crime versus Crime Severity: Do not abandon the count-based model just yet.” Crime Science.
  • Rothwell, S., McFadzien, K., Strang, H., Hooper, G. and Pughsley, A. (2022). FAST Policing by Telephone: a Randomised Controlled Trial.  Cambridge Journal of Evidence-Based Policing.
  • Hodgkinson, W., Ariel, B., and Harinam, V. (2022). Comparing panic alarm systems for high-risk domestic abuse victims: a randomised controlled trial on prevention and criminal justice system outcomes. Journal of Experimental Criminology.
  • Kumar, S., Sherman, L. and Strang, H. (2022).  The Fall and Rise of Racial Inequality in London Homicides: a Challenge for Policing by Consent.  Cambridge Journal of Evidence-Based Policing.
  • Neyroud, P. W. (2021) Globalizing evidence-based policing: Case studies of community policing, reform, and diversion.  In E. L. Piza and B. C. Welsh (Eds), The Globalization of Evidence Based Policing (Innovations in Bridging the Research-Practice Divide). Routledge
  • Sherman, L. W. (2021) The Cambridge Police Executive Programme: A global reach for pracademics.  In E. L. Piza and B. C. Welsh (Eds), The Globalization of Evidence Based Policing (Innovations in Bridging the Research-Practice Divide). Routledge
  • Rothwell, S., McFadzien, K., Strang, H., Kumar, S., Hooper, G., & Pughsley, A. (2022). FAST Policing by Telephone: a Randomised Controlled Trial. Cambridge Journal of Evidence-Based Policing, 1-22.
  • Bedford, L. W. & Neyroud, P. W. (2021) ‘Organisational Learning from Field Research in Policing: How Police Can Improve Policy and Practice by Implementing Randomized Controlled Trials’.  In J. F. Albrecht & G. Den Heyer (Eds.), Enhancing Police Service Delivery: Global perspectives and contemporary policy implications. Cham, Switzerland: Springer Nature
  • Ariel, B, Bland, M. P., & Sutherland, A. (2021) Experimental Designs (part of the SAGE Quantitative Research Kit
  • Nivette, A., Zahnow, R., Ariel, B., & Eisner, M. P. (2021) 'A global analysis of the impact of COVID-19 stay-at-home restrictions on crime'. Nature Human Behaviour
  • Maskály, J., Kutnjak Ivković, S., & Neyroud, P. (2021) Policing the COVID-19 Pandemic: Exploratory Study of the Types of Organizational Changes and Police Activities Across the Globe. International Criminal Justice Review
  • Maskály, J., Kutnjak Ivković, S., & Neyroud, P. (2021) A comparative study of police organizational changes during the COVID-19 pandemic: responding to public health crisis or something else? Policing: A Journal of Policy and Practice 
  • Wu, Y.,  Sun, I. Y., Kutnjak Ivković, S., Maskály, J., Shen, S., & Neyroud, P. (2021) Explaining Stress during the COVID-19 Pandemic among Chinese Police OfficersPolicing: A Journal of Policy and Practice.
  • Petersen, K., Mouro, A., Papy, D., Castillo, N. & Ariel, B. (2021). Seeing is believing: The impact of body-worn cameras on court outcomes, a cluster randomized controlled trial in Miami Beach. Journal of Experimental Criminology.
  • Nivette, A. E., Zahnow, R., Aguilar, R., Ahven, A., Amram, S., Ariel, B., ... & Eisner, M. P. (2021). A global analysis of the impact of COVID-19 stay-at-home restrictions on crime. Nature: Human Behaviour, 1-10.
  • Langley, B., Ariel, B., Tankebe, J., Sutherland, A., Beale, M., Factor, R., & Weinborn, C. (2021). A simple checklist, that is all it takes: a cluster randomized controlled field trial on improving the treatment of suspected terrorists by the police.  Journal of Experimental Criminology
  • Bland, M. P. & Ariel, B. (2020) 'Targeting Domestic Abuse with Police Data'. Springer
  • Bland, M. P. (2020). Algorithms can predict domestic abuse, but should we let them?  In H. Jahankhani, B. Akhgar, P. Cochrane & M. Bastbaz (Eds.), Policing in the Era of AI and Smart Societies. (139-155). Springer.
  • Hiltz, N., Bland, M. P. & Barnes, G. (2020). Victim-Offender Overlap in Violent Crime: Tageting Crim Harm in a Canadian Suburb. Cambridge Journal of Evidence-Based Policing, 4(1-2), 1-11.
  • Martain, B., Harinam, V., & Ariel, B. (2020). Linking body worn camera activation with complaints: The promise of metadata. Journal of Criminology
  • Kumar, S., Sherman, L. W., & Strang, H. (2020). Racial Disparities in Homicide Victimisation Rates: How to Improve Transparency by the Office of National Statistics in England and Wales. Cambridge Journal of Evidence-Based Policing
  • Ramiz, A., Rock, P., & Strang, H. (2020). Detecting Modern Slavery on Cannabis Farms: The Challenges of Evidence. Cambridge Journal of Evidence-Based Policing

Talks and Interviews



What is Experimental Criminology?

Experimental criminology is the use of advanced experimental methods to answer key questions about the causes and responses to crime.  For example:

  • How much crime does prison prevent--or cause--for different kinds of offenders?
  • Does visible police patrol prevent crime everywhere or just in certain locations? What is the best way for societies to prevent offending from an early age?
  • How can murder be prevented among high-risk groups of young men?

Experimental criminology is scientific knowledge about crime and justice often discovered from random assignment of different conditions in large field tests. This method is the preferred way to estimate the average effects of one variable on another, holding all other variables constant While the experimental method is not intended to answer all research questions in criminology, it can be used far more often than most criminologists assume. Opportunities are particularly promising in partnership with criminal justice agencies.

The highest and best use of experimental criminology is to develop and test theoretically coherent ideas about reducing harm from crime, rather than just evaluating existing or even new interventions.  Testing key ideas, in turn, can help to accumulate an integrated body of grounded theory in which experimental evidence plays a crucial role.  When properly executed, randomised field experiments provide the ideal tests of theories about both the prevention and causation of crime.

These and other urgent questions can be answered most clearly by the use of a research design called the randomised controlled trial.  This method takes large samples of people such as those who might have been involved in crimes as victims or offenders.  It can also take numbers of places, such as schools, prisons, police beats or other units of analysis.  It then uses a statistical formula to randomly select a portion of them for one treatment, and (with equal likelihood) another portion to receive a different treatment: one of the treatments is often the current way of addressing a problem and referred to as the Control group. Any difference, on average, in the two groups in their subsequent rates of crime or other dimensions of life that are being measured can then be confidently interpreted as having been caused by the randomly assigned difference in the treatment.  All other differences, on average, between the two groups can usually be ruled out as potential causes of any difference in outcome. 

This presentation by Cambridge University describes one such experiment: Cambridge Ideas Video

Why Cambridge?

Experimental criminology is a rapidly growing field, with increasing influence on public policy decisions.   These reasons alone make it appropriate to locate the world's first Centre for Experimental Criminology at Cambridge University.  For, like experimental medicine, this branch of criminology uses a scientific method that was invented by a Cambridge scholar, Sir Ronald Aylmer Fisher, whose theoretical work on experimental methods revolutionized the study of cause and effect.   Among his many ideas was the central insight that random assignment of a consistent action across some but not all of a large population could "hold constant" the other factors that could affect any subsequent outcomes.

In 1959 Cambridge established the first Institute of Criminology in the English-speaking world, with close links to the UK government and its need for policy-relevant research.  Established in part with funds from the Wolfson Foundation at the request of Home Secretary RA Butler, the Cambridge Institute of Criminology has engaged equally with theoretical and applied questions of the causes and prevention of crime throughout its distinguished history.  These questions were of great interest to the Institute's founder, Sir Leon Radzinowicz, as well as to two of the previous Directors: Sir Anthony Bottoms and Professor Friedrich Losel.  They have also been of particular interest to the Institute's polymath of all branches of criminology, Professor David Farrington, who co-founded the Academy of Experimental Criminology in 1998 and served as its President (2001-2004).  The Centre’s current Director, Dr Heather Strang, was also its President (2019-2022).

For these and other reasons, the Jerry Lee Foundation decided in 2006 to assist in the founding of the first university centre devoted solely to the advancement of experimental criminology.  With the Lee Foundation's initial pledge to fund a programme of pre-doctoral and post-doctoral 'Jerry Lee Scholars', the University agreed to have the Jerry Lee Centre of Criminology established in the Law Faculty's Institute of Criminology in 2007. In that same year Lawrence Sherman, the University's 4th Wolfson Professor of Criminology, was appointed the first Director of the Jerry Lee Centre.

This appointment also marked ten years of a continuing collaboration between Lawrence Sherman and the Foundation's President, Jerry Lee, who has championed social science research in business and government for decades.  Their collaboration includes contributions to the founding of the Stockholm Prize in Criminology; the Jerry Lee Center of Criminology and the Department of Criminology at the University of Pennsylvania; the Division of Experimental Criminology of the American Society of Criminology; and other initiatives for advancing the institutional development of criminology.  This includes the largest programme of multiple randomized trials of a single crime prevention strategy ever conducted in experimental criminology, the Jerry Lee Programme of Randomized Controlled Trials in Restorative Justice, a series of 12 field experiments involving over 3,000 crime victims and offenders.

What does the Centre do?

The Jerry Lee Centre for Experimental Criminology at Cambridge has two primary tasks:

  • To conduct research, with emphasis upon primary and secondary analyses of randomized controlled experiments in crime and justice.
  • To select and train an outstanding cadre of experimental criminologists for the future. 

The Centre's research programme is currently focused in these major areas:

  • The prediction and prevention of serious violence, both in high-crime places and with high-risk offenders. This includes various initiatives with UK police and health agencies, as well as with Philadelphia's Adult Probation and Parole Department. The first paper of this project on forecasting homicide was published by the Journal of the Royal Statistical Society
  • A longstanding interest of the Centre is in restorative justice, through the multi-national efforts to follow up 12 different experiments from Australia to the UK. This includes its responsibility for the first Campbell Collaboration's systematic review of the effects of face-to-face restorative justice on crime victims and offenders, published in 2013 and now being updated.
  • The most rapidly-growing area is the conduct of field experiments in collaboration with UK police agencies, on a variety of topics including the Birmingham Turning Point Project, led by Centre Fellow Professor Peter Neyroud and supported by Centre members Sumit Kumar and Dr. Sara Valdebenito
  • A rising area of research is the prediction and prevention of police misconduct, which is supported by data-sharing with the College of Policing. In the first study of the national Barred List of officers dismissed for gross misconduct, Professor Sherman and Dr. Valdebenito are working with MSt graduate Paul Tomlinson to complete a case-control study of some 6000 UK police officers to identify the most serious risk factors at the time of vetting.

With the objective of training outstanding future experimental criminologists, the Centre has pledged to fund a programme of doctoral studentships at the Institute of Criminology for students who have been admitted to the doctoral programme on a part-time basis.  To be eligible for this funding students will be in employment, most likely in a criminal justice agency, and be eligible to pay home fees.  The studentships will cover annual part-time fees up to a maximum of five years’ study. They will be awarded to applicants who can deliver a high-quality experiment in the context of their employment, for example a randomised controlled trial, where the employer will allow and accommodate study for a PhD.


The Future

The many advantages of experimental methods help explain why this branch of criminology is growing rapidly.  Just since 2005, the field has seen its first journal established (Journal of Experimental Criminology), its own separate Division of Experimental Criminology within the American Society of Criminology, and the first University centre dedicated solely to this field: the sponsor of this page, the Jerry Lee Centre for Experimental Criminology at Cambridge University.  All these institutions are dedicated to making the most of the better knowledge experiments can bring.

Yet these advantages depend entirely on the capability of the experimenters to insure success in achieving the many necessary elements of an unbiased comparison.  Many, if not most, randomised field experiments in criminology suffer flaws that could have been avoided with better planning.  The lack of such planning, in turn, may be due to the scant attention paid to field experiments in research methods texts and courses.  Even skilled, senior researchers can make basic mistakes when conducting field experiments, since experiments require a very different set of skills and methods than the normal science of observational criminology.

For further information about experiments in criminology please contact Dr. Heather Strang or any of the Cambridge criminologists cited on this website.  .

For other global institutions in experimental criminology, please click on the following links: