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Institute of Criminology



Welcome to the Jerry Lee Centre of Experimental Criminology.  The Jerry Lee Centre of Experimental Criminology at the University of Cambridge Institute of Criminology conducts and synthesizes randomized controlled trials of policing, criminal justice and crime prevention programmes, in tandem with training doctoral and post-doctoral students the methods and practices of experiments in crime and justice.  The Centre's mission is to produce better evidence for advancing human liberty.  Founded in 2007 with support from the Jerry Lee Foundation of Philadelphia, the Cambridge Centre works closely with the Jerry Lee Center of Criminology at the University of Pennsylvania.  In collaboration with the Australian National University, these centres jointly operate the Jerry Lee Program of Randomized Controlled Trials in Restorative Justice, a series of 12 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, including homicide.

Centre Members


Heather Strang

Director of


Lawrence Sherman

Chief Analyst

(Professor of Experimental Criminology)

Research Fellows

(Associate Professor in Evidence-Based Policing)


(Associate Professor in Applied Criminology)

PhD Students



News from the Centre

Research News


Talks and Interviews



What is Experimental Psychology?

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

  • 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 crime from an early age?
  • How can murder be prevented among high-risk groups of young men?

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

These and other urgent questions can be answered most clearly by the use of a research design called the randomized controlled trial.

This method takes large samples of people - or places, or schools, prisons, police beats or other units of analysis - who might become, or have already been, involved in crimes, either as victims or offenders.  It then uses a statistical formula to select a portion of them for one treatment, and (with equal likelihood) another portion to receive a different treatment.  Any difference, on average, in the two groups in their subsequent rates of crime or other dimensions of life can then be 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 the difference in outcome.  That is because with large enough samples, random assignment usually assures that there will be no other differences between the two groups except the treatment being tested.

Why Cambridge?

Experimental criminology is a rapidly growing field, with increasing influence on public policy decisions.  It has already shown how to prevent millions of violent crimes, as well as unnecessary pre-trial detention of millions of people.  These reasons alone make it appropriate to locate the world's first Centre of Experimental Criminology at Cambridge University.  For, like experimental medicine, this branch of criminology uses a scientific method that was invented by a Cambridge graduate, Sir Ronald Aylmer Fisher, whose theoretical work on experimental methods revolutionized the study of cause and effect.  In his time at Cambridge Fisher won the undergraduate mathematics prize and later spent 17 years as Professor of Genetics.  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).

For these and other reasons, the Jerry Lee Foundation decided in 2006 to offer 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 bench 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 Centre 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.

A recent independent evaluation of seven of these Jerry Lee Programme experiments, conducted by Professor Joanna Shapland and her team, found an overall 27% reduction in the frequency of re-convictions of offenders two years after random assignment to restorative justice meetings, compared to similar consenting offenders who were chosen for the control group.

What does the Centre do?

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

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



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

  • One is restorative justice, through the multi-national efforts noted above. This includes its responsibility for the Campbell Collaboration's systematic review of the effects of face-to-face restorative justice on crime victims and offenders.
  • A second area of research is homicide prediction and prevention. 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 (Series A).
  • The third and most rapidly-growing area is the conduct of field experiments in collaboration with UK police agencies, led by the Greater Manchester Police in its TEST (Tactical Experiments and Strategic Testing Program.


The Centre will carry out its training mission by recruiting and training highly effective people to design key experiments in crime and justice, to obtain funding and agency partners for conducting the experiments, and to analyze and report the results of these experiments with integrity and insight.  These tasks go well beyond the standard skill-set found in observational or analytic criminology, and are especially dependent on the interpersonal and emotional intelligence of the scholar.  People with excellent academic achievements are especially welcome to apply for the fully-funded Jerry Lee Scholarships to pursue pre- and post-doctoral training in experimental criminology.  Those who show, in addition to excellence at writing and thinking, the best evidence of ability to create and lead research projects will be the most competitive.

Anyone interested in applying to the programme can gather further information from the Centre Director, .


We are currently engaged in several vital projects to advance our field, including:


REX-COST is an acronym of Registry of EXperiments in COrrections Strategy and Tactics

All submissions for this registry should be sent, in CrimPORT format, to .

Registry of Experiments

  1. Criminological Protocol for Operating Randomized Trials, Ruback 2012
  2. Do offenders discover the harm of their offences? A multi-site randomised controlled trial evaluation of the Sycamore Tree Programme, Wilson 2013


REX-POST is an acronym of Registry of EXperiments in POlicing Strategy and Tactics

All submissions for this registry should be sent, in CrimPORT format, to .

Registry of Experiments

  1. West Midlands Police
  2. Operation Beck
  3. Operation Turning Point
  4. The Salt Lake City Court-Mandated Restorative Justice Treatment For Domestic Batterers Experiment - Part I
  5. The Rialto Police Department Wearable Cameras Experiment
  6. Western Australia Police Body Worn Video Experiment
  7. R-TREC - Protocol for Efficiacy Trials

Armed Police

Experimental criminology is scientific knowledge about crime and justice 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

Police Vans

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 government programs.  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, randomized field experiments provide the ideal tests of theories about both the prevention and causation of crime.

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, randomized 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.

This web page is intended to help foster better experiments in criminology, in three ways:

  1. Providing a format for experimental planning, called protocols.
  2. Providing registries for criminology experiments, where protocols can be transparent and credible.
  3. Providing links to people doing experimental criminology, to foster more communication.

For further information about experiments in criminology please contact 

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