By Charles Branas, Shani Buggs, Jeffrey A. Butts, Anna Harvey, Erin M. Kerrison, Tracey Meares, Andrew V. Papachristos, John Pfaff, Alex R. Piquero, Joseph Richardson Jr., Caterina Gouvis Roman, and Daniel Webster

This report summarizes the collective judgment of an experienced group of researchers who were free to consider all evidence, unconstrained by the conventional priority given to randomized controlled trials (RCT). The most rigorous studies in the field of community violence are RCTs, but many focus on individual behaviors only, failing to account for the full social context giving rise to those behaviors, including social and economic inequities, institutionalized discrimination, and the racial and class biases of the justice system itself. To synthesize evidence in an inclusive manner, one must be aware of social context and prioritize solutions that help to address structural impediments while still providing immediate interventions to reduce violence. Unless research evidence is considered in this context, potentially effective strategies may be overlooked simply because they target community-level change rather than individual change, and for that reason are difficult to evaluate and the research literature to back them up is inevitably less rigorous and less prominent.

New York: John Jay College Research Advisory Group on Preventing and Reducing Community Violence, 2020. 42p.

By Lorraine Mazerolle,Adrian Cherney,Elizabeth Eggins,Lorelei Hine and Angela Higginson

Multiagency responses to reduce radicalisation often involve colla-borations between police, government, nongovernment, business and/or community organisations. The complexities of radicalisation suggest it is impossible for any single agency to address the problem alone. Police‐involved multiagency partner-ships may disrupt pathways from radicalisation to violence by addressing multiple risk factors in a coordinated manner.Objectives:1. Synthesise evidence on the effectiveness of police‐involved multiagency interventions on radicalisation or multiagency collaboration. Qualitatively synthesise information abouthowthe intervention works (me-chanisms), interventioncontext(moderators), implementation factors and eco-nomic considerations.Search Methods:Terrorism‐related terms were used to search the Global PolicingDatabase, terrorism/counterterrorism websites and repositories, and relevantjournals for published and unpublished evaluations conducted 2002–2018. Thesearch was conducted November 2019. Expert consultation, reference harvestingand forward citation searching was conducted November 2020.Selection Criteria:Eligible studies needed to report an intervention where policepartnered with at least one other agency and explicitly aimed to address terrorism,violent extremism or radicalisation. Objective 1 eligible outcomes included violentextremism, radicalisation and/or terrorism, and multiagency collaboration. Only impact evaluations using experimental or robust quasi‐experimental designs were eligible. Objective 2 placed no limits on outcomes. Studies needed to report anempirical assessment of an eligible intervention and provide data on mechanisms,moderators, implementation or economic considerations.Data Collection and Analysis:The search identified 7384 records. Systematic screening-identified 181 studies, of which five were eligible for Objective 1 and 26 for Objective 2.

Oslo, Norway: Campbell Collaborative, 2021. 88p.

By Cynthia Lum, Christopher S. Koper, David B. Wilson, Megan Stoltz, Michael Goodier, Elizabeth Eggins, Angela Higginson and Lorraine Mazerolle

Law enforcement agencies have rapidly adopted body-worn cameras (BWCs) in the last decade with the hope that they might improve police conduct, accountability, and transparency, especially regarding use of force. Overall, there remains substantial uncertainty about whether BWCs can reduce officer use of force, but the variation in results over studies suggests there may be conditions in which BWC could be effective. BWCs also do not seem to affect other police and citizen behaviors in a consistent manner, including officers’ self-initiated activities or arrest behaviors, dispatched calls for service, or assaults and resistance against police officers. BWCs can reduce the number of citizen complaints against police officers, but it is unclear whether this finding signals an improvement in the quality of police-citizen interactions or a change in reporting.

Research has not directly addressed whether BWCs can strengthen police accountability systems or police-citizen relationships. Overall, the way BWCs are currently being used may not substantially affect most officer or citizen behaviors. The use of BWCs does not have consistent or significant effects on officers’ use of force, arrest activities, proactive or self-initiated activities, or other measured behaviors. Nor do BWCs have clear effects on citizens’ calls to police or assaults or resistance against officers. Analysis suggests restricting officer discretion in turning on and off BWCs may reduce police use of force, but more assessment is needed.

Oslo, Norway: Campbell Collaborative, 2020. 40p.

By Chuka Emezue, Jo-Ana D. Chase,Tipparat Udmuangpia and Tina L. Bloom

A growing body of research shows the promise and efficacy of technology-based or digital interventions in improving the health and well-being of survivors of intimate partner violence (IPV). In addition, mental health comorbidities such as anxiety, post-traumatic stress disorder (PTSD), and depression occur three to five times more frequently in survivors of IPV than non-survivors, making these comorbidities prominent targets of technology-based interventions. Still, research on the long-term effectiveness of these interventions in reducing IPV victimization and adverse mental health effects is emergent. The significant increase in the number of trials studying technology-based therapies on IPV-related outcomes has allowed us to quantify the effectiveness of such interventions for mental health and victimization outcomes in survivors. This meta-analysis and systematic review provide critical insight from several randomized controlled trials (RCTs) on the overall short and long-term impact of technology-based interventions on the health and well-being of female IPV survivors.

Oslo, Norway: Campbell Collaborative, 2022. 69p.

By William H. Sousa and George L. Kelling

This study evaluates explanations that have been advanced for the sharp decline in crime in New York City during the 1990s. The authors consider arguments that crime in New York City during the 1990s. The authors consider arguments that crime drops have been the result of socio-economic factors, such as an improving economy, falling numbers of teenaged males, and declining use of crack cocaine. They also consider the argument that police interventions—particularly the enforcement of laws against minor crimes, known as "broken windows" policing—played a major role.

New York: Manhattan Institute, Center for Civic Innovation, 2001. 32p.

By Jonathan P. Caulkins and Keith Humphreys

Drug policy often comprises efforts to reduce the supply of drugs, to provide health and social services to addicted individuals, and to prevent the development of addiction in the first place. The last of these efforts—prevention—is the subject of this paper. The scientific literature on drug policy offers some insights on the relative effectiveness and cost-effectiveness of different strategies for preventing traditional opioid misuse and related harm. But these insights don’t apply perfectly to the current opioid crisis in the U.S. and Canada, due to many important differences between today’s epidemic and those of the past (e.g., heroin in the 1960s and 1970s). School-based universal primary prevention programs, for example, will probably remain only modestly effective, mainly because it is mostly adults, rather than adolescents, who initiate opioid use through prescription drugs. However, there are new opportunities for prevention, including promoting safer opioid prescribing, and issuing public health warnings about fentanyl’s dangers and the need to keep prescription opioids locked up. Importantly, the audience for these prevention interventions can include prescribers and pharmacists, not just potential users, and the mechanisms should involve incentives and nudges, not just information and education. Classic drug law enforcement against retail sellers and their suppliers may become even less effective than it has been in the past. However, other forms of supply control are possible because most of the prescription opioids that get misused come from legal and regulated distribution. Because prescription opioids remain the dominant route through which opioid use disorder is initiated, reducing its incidence can translate over time into reduced deaths not only from prescription opioids, but also from heroin and fentanyl. Enforcement against licensed producers and distributors may perform well even if enforcement against traditional dealers does not, and there are a wide range of actions visa-vis these licensees that do not require arrest or incarceration.

Washington, DC: The Brookings Institution, 2020. 24p.

By Liz Ward, Sian Nicholas and Maria Willoughby

The Tackling Knives Action Programme (TKAP) ran initially from June 2008 until March 2009 and aimed to reduce teenage knife crime in ten police force areas in England and Wales. TKAP Phase II was then launched and the programme re-branded into the Tackling Knives and Serious Youth Violence Action Programme. Phase II ran from April 2009 to March 2010 in 16 police force areas (the original ten TKAP forces and six new areas)1 and aimed to reduce all serious violence involving 13- to 24-year-olds using a range of enforcement, education and prevention initiatives.

London: Home Office, 2011. 67p.

The Knife Crime Prevention Programme: Process Evaluation

By Grant Thornton UK LLP

The Knife Crime Prevention Programme (KCPP) is an intervention which aims to reduce the prevalence of knife carrying and use by young people. Young people are referred to the programme if they are aged between 10 and 17 and have been convicted of an offence where a knife or the threat of a knife is a feature. The programme is based on a national delivery framework, with flexibility for local adaptation. It was rolled out as part of the Home Office ‘Tackling Knives Action Programme’ (TKAP). This process evaluation was commissioned to:  provide a picture of the implementation and delivery of KCPP  explore participants’ knowledge, perceptions and attitudes to knife crime before and after the programme  explore staff attitudes to the programme.

London: Youth Justice Board for England and Wales 2013. 29p.

By Kin Y. Ma

Over the past two decades, gang-related violence and control has plagued the Northern Triangle: the Central American (NTCA) countries of El Salvador, Honduras, and Guatemala. This gang-related behavior has propelled the countries to exhibit some of the highest homicide rates per capita globally, contributing to state fragility and mass emigration – most notably to the United States and Mexico. Mitigating such gang influence can be taxonomized into two areas: anti-gang activities focusing on recruitment prevention efforts, and counter-gang operations centered around disrupting, dismantling, or denying gang activities via law enforcement efforts. Scholars and subject-matter experts on gang influence both overwhelmingly agree and exhort that reducing gang membership remains a key factor in lessening a gang’s impact in a given area, as well as potentially yielding a more effective outcome than solely relying on the disruption provided by counter-gang operations. In view of this consensus, the scope of this study focuses specifically on gangprevention efforts in the economic, community outreach, and law enforcement sectors over the past two decades, while concurrently examining US-involved programs and their impact from a qualitative perspective. Most prior academic work on the topic consists of an overarching view of the totality of the programs. As such, this study either increases, updates, or combines the research conducted by the US government, academic community, field researchers, as well as the author’s original research conducted in either the NTCA or with officials inside the respective countries. As a result, this study confirms and furthers reasoning for the existing consensus, and moreover, coalesces the wide-ranging research existing in academia, US diplomatic efforts, and Guatemalan government efforts, as well as delving into program specifics existing in academia, US diplomatic efforts, and Guatemalan government efforts, as well as delving into program specifics

Cambridge, MA: Harvard University, 2021. 114p.

By Kristy Docherty and Brigid Russell

The purpose of this report is to present the findings of the evaluation of the Police Scotland and Local Government Collaborative Leadership Pilots (hereafter referred to as ‘the programme’). This evaluation has been undertaken independently by Dr Kristy Docherty and Brigid Russell on behalf of the Scottish Institute for Policing Research (SIPR) between August 2021 and February 2022. The objectives of the evaluation were: • To critically examine the programme. • To capture and analyse information about the activities, processes, characteristics, and outcomes of the programme. • To offer insights and suggestions for future action with the purpose of improving programme effectiveness, and/or to inform and shape future programme decisions. It is important to note that our evaluation took place while the programme was still running, participants were at various stages and they had not completed all of their sessions. This ‘formative’ approach was deliberate and links in principle with the embedded evaluation process adopted by the facilitation team.

Edinburgh: Scottish Institute for Policing Research. 2022. 68p.

By Daniel Mejía, Ervyn Norza, Santiago Tobón, and Martín Vanegas-Arias

We study the effects of broken windows policing on crime using geo-located crime and arrest reports for 80 Colombian cities. Broadly defined, broken windows policing consists of intensifying arrests -sometimes for minor offenses- to deter potential criminals. To estimate causal effects, we build grids of 200 × 200 meters over the urban perimeter of all cities and produce event studies to look at the effects of shocks in police activity in the periods to follow. We use spikes in the number of arrests with no warrant -which are more likely associated with unplanned police presence- as a proxy for shocks in broken windows policing. As expected, we observe an increase in crimes during the shock period, as each arrest implies at least one crime report. In the following periods, crimes decrease both in the place of the arrests and the surroundings. With many treated grids and many places exposed to spillovers, these effects add up. On aggregate, the crime reduction offsets the observed increase during the shock period. Direct effects are more immediate and precise at low crime grids, but beneficial spillovers seem more relevant at crime hot spots. The effects of broken windows policing circumscribe to cities with low or moderate organized crime, consistent with criminal organizations planning their activities more systematically than disorganized criminals.

Bogotá, Colombia: Universidad de los Andes–Facultad de Economía–CEDE, 2022. 34p.

By Mateo Dulce Rubio

I use residential burglary data from Bogota, Colombia, to fit an agent-based model following truncated L´evy flights (Pan et al., 2018) elucidating criminal rational behavior and validating repeat/near-repeat victimization and broken windows effects. The estimated parameters suggest that if an average house or its neighbors have never been attacked, and it is suddenly burglarized, the probability of a new attack the next day increases, due to the crime event, in 79 percentage points. Moreover, the following day its neighbors will also face an increment in the probability of crime of 79 percentage points. This effect persists for a long time span. The model presents an area under the Cumulative Accuracy Profile (CAP) curve, of 0.8 performing similarly or better than state-of-the-art crime prediction models. Public policies seeking to reduce criminal activity and its negative consequences must take into account these mechanisms and the self-exciting nature of crime to effectively make criminal hotspots safer.

Bogotá, Colombia: Universidad de los Andes–Facultad de Economía–CEDE, 2019. 29p.

By Juan Felipe García, Daniel Mejia, and Daniel Ortega .

The Plan Nacional de Vigilancia Comunitaria por Cuadrantes (PNVCC) is a new police patrolling program introduced in the eight major cities of Colombia in 2010 by the National Police. The strategy divides the largest cities into small geographical areas (cuadrantes), assigns six policemen to each, establishes a new patrolling protocol involving more community contact, and holds officers accountable for crime in their assigned area. The plan warranted a comprehensive training program for over 9,000 police officers aimed at improving interpersonal skills and implementation of the new patrolling protocols. By staggering the training schedule between three randomly chosen cohorts of police stations, we generate experimental variation in the exposure to training and in the effective implementation of the new police protocols induced by the Plan Cuadrantes. Comparing the 4 months immediately after training with the same months from the previous year, we find a significant reduction in several types of crime attributable to the training program, ranging from around .13 of a standard deviation for homicides to .18 of a standard deviation for brawls. These impacts are driven by very large effects in high crime areas and very small -or zero- effects in low crime neighborhoods. Once we take into account the high spatial concentration of crime, the estimated effects account for an overall reduction in the number of homicides of about 22%. We suggest that the training program affected crime by increasing the patrol police’s sense of accountability to the population and also possibly through higher police motivation. Large efficiency gains in public service provision may be attainable with relatively inexpensive interventions that bring public servants closer to their clients.

Bogotá, Colombia: Universidad de los Andes–Facultad de Economía–CEDE, 2013. 27p.

By Daniela Collazos, Eduardo García, Daniel Mejía, Daniel Ortega, and Santiago Tobón

Objectives: Test direct, spillover and aggregate effects of hot spots policing on crime in a high crime environment. Methods: We identified 967 hot spot street segments and randomly assigned 384 to a six-months increase in police patrols. To account for the complications resulting from a large experimental sample in a dense network of streets, we use randomization inference for hypothesis testing. We also use non-experimental streets to test for spillovers onto non-hot spots, and examine aggregate effects citywide. Results: Our results show an improvement in short term security perceptions and a reduction in car thefts, but no direct effects on other crimes or satisfaction with policing services. We see larger effects in the least secure places, especially for short term security perceptions, car thefts and assaults. We find no evidence of crime displacement but rather a decrease in car thefts in nearby hot spots and a decrease in assaults in nearby non-hot spots. We estimate that car thefts decreased citywide by about 11 percent. Conclusions: Our study highlights the importance of context when implementing hot spots policing. What seems to work in the U.S. or even in Bogotá is not as responsive in Medellín (and vice versa). Further research¿especially outside the U.S.¿is needed to understand the role of local crime patterns and police capacity on the effectiveness of hot spots policing.

Bogotá, Colombia: Universidad de los Andes–Facultad de Economía–CEDE, 2019. 44p.

By Jean-Pierre Guay

In Québec, street gangs are now among the newest threats to public safety (MSPQ, 2007; SPVM, 2005). Major police efforts to dismantle juvenile prostitution networks or reduce drug trafficking have escalated the flow of juvenile offenders into the adult correctional system. Gang members are a growing presence in the penal system and, to a certain degree, risk assessment creates its own problems. The objective of this research is to examine the applicability of the LS/CMI (Andrews, Bonta, & Wormith, 2004) to gang members and to identify specific criminogenic needs profiles compared to non-gang offenders. A sample of 172 offenders serving sentences of more than six months under provincial jurisdiction was used within this framework. Eighty-six offenders, identified by the Ministère de la Sécurité publique du Québec, were paired by age, status and city of residence with 86 offenders not identified as gang members. All were assessed with the LS/CMI. Data on new arrests and new convictions were used afterward to test the predictive validity of the LS/CMI. The results indicate that gang members present more diverse criminal histories and greater prevalence of convictions for violent offences. The LS/CMI data analysis showed that gang members present more significant criminogenic risks and needs, and in a greater number of areas than did the control group subjects. These higher needs translated into higher rates of re-arrest and substantially more convictions for violent crimes. The LS/CMI was also useful in predicting recidivism for gang members. Multivariate analyses with the Cox proportional hazard model suggest that, at equal risk, gang offenders are arrested more frequently for both general crimes and violent crimes. Age and equal risk factors also apply to new convictions for violent crimes; gang members are more likely to face new convictions than are non-members. The implications of these results are discussed.

Ottawa: Public Safety Canada, 2012. 35p.

By Rob C. Mawby

The major areas of research covered in this study of the influence of the media on police work are covered in eight chapters. In chapter 1 a History of Police Image Work From 1829 to 1987 traces the history of image work. Chapter 2 the Professionalizing of Police Image Work Since 1987 discusses the distinguishing features of the most recent phase of police image work. Chapter 3 Police Legitimacy, Communication and the Public Sphere introduces theoretical concerns, and the nature of police communications. Chapter 4 the National Picture: Systems of Police Image Work looks at the terrain of contemporary image work across the police service nationally. Chapter 5 One Force and Its Image provides historical background of the force and outlines the 1984-85 Miners' Strike and the 1989 Hillsborough tragedy. Chapter 6 Press and Public Relationship Officers At Work examines news management and the planning and delivery of set piece promotional events. Chapter 7 Image Work in Routine Policing looks at three areas of practical policing. In the final chapter, Image Work, Police Work and Legitimacy the author considers the extent to which image work pervades contemporary police work and the implications for policing in the context of a highly mediated society. The study concludes that the mass media has played an important role in shaping police work, image work, the legitimization of policing. The media and the police will continue to work together to influence policing and society.

Cullompton, Devon, UK: Willan Publishing, 2002. 226p.

By Mark Button

Over the past few years there has been exponential growth in the private security industry as concerns about safety and risk have become increasing preoccupations in the western world. At the same time there has been a huge change in the balance and structure of policing in the direction of fragmentation and pluralisation. This book meets the need for a concise and up-to-date account of private policing, situating it within the context of the debates on policing more generally and the changing relationship between public and private policing. Private Policing examines the origins of private policing, the growing literature that has sought to explain its growth, and ways in which it has been defined and classified. These include the commercial security industry, policing functions exercised by the armed forces, local authorities, state departments and by voluntary policing bodies. The increasingly important issue of patrol by private policing bodies provides the focus for an important case study, exploring the implications of the exercise of patrol powers and functions by neighbourhood wardens, patrolling security officers and others.

Cullompton, Devon, UK: Willan Publishing, 2002. 176p.

By D. Elaine Pressman

Risk factors for violent individuals have been used in risk assessment protocols for decades. Such tools and guides have been shown to be a valid and reliable way to assess risk of future violence. The risk assessment protocols currently available, however, have questionable relevance to violent extremists and terrorists because the factors used to assess risk do not relate to the background and motivations of this group of violent actors. The need was identified for a relevant tool for the population of violent ideologically motivated extremists. Approaches to risk assessment for violence are described in the document. These include unstructured clinical judgment, actuarial approaches and structured professional judgment (SPJ). Unstructured approaches have been criticized for not demonstrating high validity or good inter-rater reliability. Given the low base rate of violent extremists, it is difficult to create empirically based actuarial prediction instruments for violent extremism. The structured professional judgment approach (SPJ) has been used successfully with forensic populations and was considered appropriate for a tool to address risk assessment for the population of violent extremists. As current SPJ guides were found to be inadequate to address the specific historical and contextual features of violent extremists, a new SPJ guide was developed and is described in this document. The major goals of the project were to identify and compare the specific characteristics and factors of those who perpetrate “general” criminal violence and those who perpetrate ideologically motivated violence, to highlight the salient differences among the historical, contextual, attitudinal and protective risk factors of these types of criminal violence and to construct a new tool to assess the risk of violence in ideologically motivated extremists. ‘Political violence’, ‘radicalization’, ‘extremism’ and ‘terrorism’ were defined and elaborated in the document. The most significant risk factors relevant to violent extremism and terrorism were extracted from the literature and organized into a structured professional judgment (SPJ) protocol. Five categories were identified as risk factors and relevant items were identified for each category. These categories are modeled after other well-established SPJ tools but are item specific to violent extremism. The categories include attitude factors, contextual factors, historical factors, protective factors and demographic factors. A preliminary model for the assessment of de-radicalization and disengagement efficacy was proposed. The new SPJ protocol, Violent Extremist Risk Assessment or VERA is designed to be used with persons having a history of extremist violence or having been convicted of such offences. At this stage of development, the VERA is a conceptual “research” tool intended to generate debate and discussion.

Ottawa: Public Safety Canada, 2009. 44p.

By Kathryn M. Roberts

"Countering the radical Islamist narrative remains a high-profile priority of the United States in its ongoing efforts to counter domestic violent extremism. Since mid-2014, government officials have condemned the United States as unable to muster a satisfactory 'counter-narrative,' and emphasize the potentially devastating consequences of failure. Experts inside and outside the government describe the Islamic State as masters of the internet capable of reaching into the United States and turning its people into hate-filled, violently inspired terrorists at will. The idea that the United States must aggressively work to counter these messages domestically remains a given; but should it? The focus of this thesis is to examine current U.S. efforts in counter-messaging to determine why the United States believes it is failing, and what, if any, evidence supports the idea that a counter-narrative or counter-messaging should be part of domestic countering violent extremism (CVE) programs. Review of official documents found little basis to assess U.S. programs, as no meaningful published strategy, objectives, or performance data exist for current efforts. Moreover, the foundational assumptions underlying current programs suggest malalignment between what U.S. officials desire a counter-messaging effort to accomplish and what is realistically achievable. Based on these findings, it is recommended that domestic CVE programs eliminate counter-messaging from their portfolio."

Monterey, CA: Naval Postgraduate School, 2020. 119p.

National Academies of Sciences, Engineering, and Medicine.

Proactive policing, as a strategic approach used by police agencies to prevent crime, is a relatively new phenomenon in the United States. It developed from a crisis in confidence in policing that began to emerge in the 1960s because of social unrest, rising crime rates, and growing skepticism regarding the effectiveness of standard approaches to policing. In response, beginning in the 1980s and 1990s, innovative police practices and policies that took a more proactive approach began to develop. This report uses the term “proactive policing” to refer to all policing strategies that have as one of their goals the prevention or reduction of crime and disorder and that are not reactive in terms of focusing primarily on uncovering ongoing crime or on investigating or responding to crimes once they have occurred.

Proactive policing is distinguished from the everyday decisions of police officers to be proactive in specific situations and instead refers to a strategic decision by police agencies to use proactive police responses in a programmatic way to reduce crime. Today, proactive policing strategies are used widely in the United States. They are not isolated programs used by a select group of agencies but rather a set of ideas that have spread across the landscape of policing.

Proactive Policing reviews the evidence and discusses the data and methodological gaps on: (1) the effects of different forms of proactive policing on crime; (2) whether they are applied in a discriminatory manner; (3) whether they are being used in a legal fashion; and (4) community reaction. This report offers a comprehensive evaluation of proactive policing that includes not only its crime prevention impacts but also its broader implications for justice and U.S. communities.

Washington, DC: The National Academies Press. 2018. 408p. .