Effectiveness Of Closed Circuit Television Research Articles

How CCTV shapes perceptions of safety in London’s public transport: a quantitative analysis

ABSTRACT The perception of safety while using public transportation varies among individuals, influenced by personal experiences and individual characteristics. Closed-circuit television (CCTV) systems are commonly employed to deter crime in public areas, including transit environments where safety concerns are prevalent. This study aims to scientifically assess the effectiveness of CCTV in enhancing the perceived safety of public transportation users. A comprehensive survey was conducted, involving over 200 students from various universities to ensure a representative sample. The survey targeted public transportation users and focused on their sense of security in relation to the presence of CCTV. Through quantitative analysis, three specific research questions were addressed. The results indicate that the presence of CCTV alone is insufficient to significantly improve feelings of safety among public transportation users. These findings suggest important policy implications: enhancing perceived safety in public transportation requires more than just the implementation of security measures. It is essential to inform and educate the public about actual crime rates, existing security measures, and the importance of crime reporting. This comprehensive approach can more effectively address the multifaceted nature of safety perception in public transportation.

The Impact of Spatial Changes on the Assessment of CCTV Effects: An Example of the Green Light Project in Detroit

The assessment of closed-circuit television (CCTV) as an infrastructure designed to improve the policing environment has gained widespread attention. The effect of CCTV is influenced not only by the time of installation, however, but also by locations, making it challenging to assess accurately from a single dimension. Existing studies have analyzed the differences in assessment results due to the period of installation, but little has been said about the sensitivity of assessment results to spatial changes. Moreover, existing assessment results rarely consider the varying degrees of influence that CCTV might have in different locations. To address these issues, we use the weighted displacement quotient (WDQ) algorithm to assess the effect of 603 CCTVs installed by the Green Light Project in Detroit from 2016 to 2019. This assessment examines the sensitivity of the WDQ algorithm to spatial changes, particularly when the radius of the target area is altered. We also optimize the matching algorithm and consider the spatial heterogeneity of CCTV’s effects in the assessment process. The results show that over 50 percent of the CCTVs installed have a diffusion of benefits on crime reduction (WDQ > 0), and the assessment results obtained using the WDQ algorithm are highly sensitive to spatial changes. These findings provide valuable insights for subsequent assessments of CCTV, and for the optimization of CCTV installation and layout to enhance their effect.

Cost-Effectiveness of CCTV Surveillance Systems: Evidence from a Polish City

Closed-circuit television (CCTV) surveillance has been increasingly popular worldwide as a crime prevention measure, while its effectiveness, efficiency, and related privacy issues are debated. In this paper, we investigated whether the municipal CCTV surveillance system is cost-effective in the case study of Poznan, Poland. The analysis comprised (a) the preventive effectiveness of CCTV, (b) costs of CCTV surveillance system installation and operation, and (c) costs of crime. We collected police data on three categories of street crimes: (a) car burglary/theft, (b) car damage, and (c) robbery, as well as data on the costs of CCTV surveillance system construction and maintenance. We searched for a year after installing the CCTV system when the accumulated, hypothetical financial cost of crime was higher than the actual accumulated cost of crime and CCTV installation and maintenance in any treatment area. The number of crimes in a given category was predicted based on a comparable control area, where there were no cameras. Our study suggests that CCTV surveillance is cost-ineffective in most areas. This result implies the cautious development of CCTV surveillance, taking into account the target crime types and costs, including social costs and benefits. Evaluating cost-effectiveness, although considered as a robust measure, is in practice difficult. However, analysis of the correlation between land use characteristics and cost-effectiveness may provide practical advice on where to develop CCTV surveillance monitoring.

Private Security and Closed-Circuit Television (CCTV) Surveillance: A Systematic Review of Function and Performance

Private security personnel play an important but largely overlooked role in the operation of closed-circuit television (CCTV) surveillance to prevent crime in public and private areas. This role can take a number of forms, including active monitoring of cameras. Drawing upon a global database of CCTV evaluations ( N = 165), this article examines the function and performance of private security personnel as related to the effectiveness of CCTV. Findings indicate that CCTV schemes operated by private security personnel generated larger crime prevention effects than those operated by police or those using a mix of police and security personnel. Policy and research implications are discussed.

CCTV surveillance for crime prevention

Research SummaryWe report on the findings of an updated systematic review and meta‐analysis of the effects of closed‐circuit television (CCTV) surveillance cameras on crime. The findings show that CCTV is associated with a significant and modest decrease in crime. The largest and most consistent effects of CCTV were observed in car parks. The results of the analysis also demonstrated evidence of significant crime reductions within other settings, particularly residential areas. CCTV schemes incorporating active monitoring generated larger effect sizes than did passive systems. Schemes deploying multiple interventions alongside CCTV generated larger effect sizes than did schemes deploying single or no other interventions alongside CCTV.Policy ImplicationsThe results of this systematic review—based on 40 years of evaluation research—lend support for the continued use of CCTV to prevent crime as well as reveal a greater understanding of some of the key mechanisms of effective use. Of particular salience is the continued need for CCTV to be narrowly targeted on vehicle crimes and property crime and not be deployed as a “stand‐alone” crime prevention measure. As CCTV surveillance continues to expand its reach in both public and private space and evolve with new technology, policy will benefit from high‐quality evaluations of outcomes and implementation.

Conditional effects of open-street closed-circuit television (CCTV) on crime: A case from Korea

Prior studies reported mixed findings concerning the effects of Closed-Circuit Television (CCTV) on crime reduction. By utilizing the multi-contextual criminal opportunity theory, this study aims to determine the conditional effects of open-street CCTV surveillance system on crime across socioeconomic and physical environmental factors. Using the data from one district in Seoul, Korea, we ran a series of Poisson regression models with interaction terms allowed for articulating the conditional effects of CCTVs on crime. In line with studies in Western countries, CCTVs in Korea were significantly associated with levels of property crime and the areas with larger surveillance zones had lower property crime levels. Also, there was a conditional crime reduction effect of CCTVs on assaults, depending on the areal density of alcohol outlets. The conditional effect of CCTVs suggests some neighborhood characteristics optimize the deployment of CCTVs, which guide more effective implementation of CCTV systems for crime control and prevention.

Crime-Reduction Effects of Open-street CCTV: Conditionality Considerations

This study addresses the conditional nature of the effectiveness of open-street CCTV (closed circuit television) by examining the differences in the effects (1) between daytime and nighttime crime, (2) between weekday and weekend crime, (3) across specific-crime offenses, and (4) depending on CCTV site characteristics, including location type (e.g. downtown, business district, school/university, or residential area) and the site’s base rate of crime. This study used HLM (hierarchical linear modeling) with 84 repeated measures across 34 camera locations in Cincinnati, Ohio, while also accounting for overlapping camera areas. Overall, the findings provided minimal evidence of the effectiveness of CCTV in reducing crime, though some types of crime were reduced in residential areas especially, and effectiveness was clearly interdependent with an area’s base rate of crime. Finally, WDQ analyses showed that diffusion of benefits occurred much more often than displacement in cases where there was a crime reduction, post-CCTV.

Life through a Lens: Risk, Surveillance and Subjectivity

Drawing on findings from a two-year empirical study examining the culture of closed-circuit television (CCTV) operation in the UK, this paper analyses how CCTV camera operators subjectively experience the visual media that they work to produce. It seeks to excavate some of the social meanings that these vicarious risk flâneurs ascribe to the telemediated events that they indirectly encounter, and how these ‘narratives of the street’ come to inscribe themselves on the subjectivities of the camera operators in a disciplinary manner. In so doing, the paper reveals the work of watching to be an ambiguous social practice, an activity that far exceeds its formal framing as a dispassionate and standardised procedure. As such, I contend that CCTV camera operators engage in two distinct modes of work – ‘surface’ and ‘deep’ – as they watch the screens and codify the spectacles that are mediated through the camera lens. The ‘surface’ work they enact is officially acknowledged and concerns their focusing attention on the screens to identify harmful behaviours, to capture evidence and to share information with other collaborators in the security network. This mode of work is principally performed for professional imperatives and economic returns. In contrast, the ‘deep’ work rituals they execute are informal in scope and therapeutic in purpose. Such individualised practices are an unseen and unrecognised work relation that mitigates the negative effects of CCTV viewing. They are operationalised through diverse behavioural repertoires which function to insulate the self from its exposure to mediated traumas, and from the contradiction of mobilising ‘(in)action at a distance’. Overall, the paper accentuates the messy realities that hinge on the practice of urban surveillance, showing these realities to be meditated by the vagaries of subjective experience and social relations.

Prevention of crime and violence: evidence-based crime prevention—a public health imperative: a review paper

BackgroundIn November, 2012, a John Moore's University publication Protecting People Promoting Health presented a public health approach to the crime prevention agenda. Sandwell Public Health Department and the Sandwell Crime and Disorder Partnership has sought to implement evidence-based interventions in its partnership work on community safety and crime prevention over many years. MethodsThe West Midlands Crimegrip project hosted by Sandwell held implementation seminars for systematic reviews of effective interventions, including methadone maintenance and harm reduction for drug problems; early-years interventions including Highscope and interactive schools drug programmes; youth mentoring programmes; street lighting; neighbourhood policing; and situational crime prevention. Three examples of strongly evidence-based programmes will be presented: a methadone maintenance programme for persistent offenders; creation of safe environments; and early years programmes for improvement of long-term health and safety. These examples show how the translation of evidence into practice is delivering improved outcomes locally. FindingsAmong these programmes are methadone maintenance and harm reduction, which produced a 30% fall in domestic burglary when clients in treatment doubled in 2004, and acquisitive crime continued to decrease. This programme has been accompanied by target hardening and repeats victim programmes, design of crime supplementary planning guidance applied to new housing developments, and other measures to reduce burglary. The effect of closed-circuit television (CCTV) continues to be challenged, but although evidence for the primary prevention of crime remains questionable, the effect in crime detection and the routine use of CCTV as a method for crime detection is unquestioned. The Greets Green New Deal for Community area reported substantial community satisfaction with improved street lighting and a reduced fear of crime, consistent with research evidence. Early years and other educational interventions have a substantial long-term effect on child protection, preventing a cycle of deprivation and abuse and preventing crime as the young people reach adulthood. Schemes implemented in Sandwell as part of a portfolio were required to include the family nurse partnership, Highscope training for nursery and primary school teachers, universal nursery school provision since 1984, teaching parenting skills through evidence-based regimens such as Triple P, use of Bookstart, and Time to talk and speech therapy interventions to improve learning outcomes. All these schemes have contributed to an increase in school readiness of 5-year-olds, and to improved GSCE outcomes and reduced teenage pregnancy rates over 15 years. Each of these measures can be taken as proxies for improved outcomes for young people and reductions in social stress and likelihood of engagement in criminal activity. InterpretationThe evidence that these interventions produced beneficial outcomes might be judged circumstantial. However, the fact that improved outcomes have been noted after implementation of evidence from good research studies should be what the research community would like to see happen and should be what the service community wants to implement. The context of this paper is therefore not one of showing what works through pure research; it seeks to show how the evidence for what works can be implemented and how improved outcomes can be delivered through knowledge of what works. This paper is therefore a discussion of how research results can be translated into service outcomes and how we can develop both knowledge transfer and public health audit. The present austerity and welfare reform policies set the conditions for extreme poverty and for exacerbation of social stress, violence, abuse, and neglect. Collective responses by the health and local authorities to protect individuals and families through welfare support mitigate but do not prevent adverse crime and social consequences. Formal research evidence for these programmes is limited in the published work but is necessary. Public health services in local authorities need to embrace a greater partnership with the public health research establishment. There remains a gap in applied health research. FundingIndividual service interventions were funded through Sandwell Primary Care Trust, Sandwell Metropolitan Borough Council, and the Safer Sandwell Partnership. Research reviews were supported by The Home Office West Midlands and the National Institute of Health Research Collaboration for Leadership in Applied Health Research and Care Birmingham and Black Country (CLARHC-BBC) programme.

The Cairns Model: Evaluating the context of an open-space, closed circuit television system in an urban centre in tropical Australia

Australian and United Kingdom evaluations of open-space, closed circuit television (CCTV) systems in urban areas were reviewed in an attempt to identify elements of good practice and assess the Cairns Regional Council's (CRC) CCTV system against them. Recommended management and operational practices were extracted from peer reviewed public health and criminological literature and government reports. These were grouped by key topics and tabulated. CRC's CCTV manuals were examined. Observational sessions, open-ended discussions and focus groups with operators and stakeholders were used to identify operational and management practices. These were then compared with those found in the literature and the results fed back to Council. We found the Cairns CCTV model generally met recommended guidelines but improvements are possible. This article also situates this study within debate surrounding the adequacy of CCTV evaluation. Our evaluation used a public health ‘continuous quality improvement’ approach incorporating elements of a criminological ‘realist evaluation’ methodology. This identified 10 contexts within which to postulate and test, with further research, the mechanisms through which the Cairns CCTV system operates. Implications for improving our understanding of the effectiveness of CCTV are discussed.

Measuring the crime displacement and diffusion of benefit effects of open-street CCTV in South Korea

Crime prevention strategies are implemented to reduce the damage caused by crimes with CCTV (Closed-Circuit Television) being broadly accepted as one of the main strategies. However, along with CCTV's perceived high expectations as crime deterrent, there is also a growing controversy over CCTV's potentially unexpected limitations. For example, the crime displacement (the presence of CCTV will change the locations of crime and its total number will not change) and the diffusion effects of crime control benefits (the crime prevention effect of CCTV may filter through to neighboring areas) are the representative controversial issues. In this study, we aimed to verify the crime displacement and the diffusion of benefit of open-street CCTV by analyzing the crime tendencies empirically.Gwang Myeong City in Gyeonggi Province, South Korea was chosen to analyze the crime displacement using the WDQ (Weighted Displacement Quotient) which compares the crime tendency of a location with that of its neighboring areas. The results showed that the crime prevention effect of the CCTV was significant. The number of robberies and thefts in the areas with CCTV installed reduced by 47.4%, while the areas without CCTV showed practically no change in the number of crimes. The crime displacement caused by the CCTV was not either found or inconsequential, and the crime rates in the neighboring areas also decreased slightly. Of major cause for concern was the fact that CCTV was marginally effective in deterring violence and as such, there should be a more detailed scientific analysis of the pattern and type of crimes committed in an area where CCTV's are being installed.

Public Area CCTV and Crime Prevention: An Updated Systematic Review and Meta‐Analysis

In recent years, there has been a marked and sustained growth in the use of closed circuit television (CCTV) surveillance cameras to prevent crime in public places in the USA and other Western nations. Amidst this expansion and the associated public expenditure, as well as concerns about their efficacy and social costs, there is an increasing need for an evidence‐based approach to inform CCTV policy and practice. This paper reports on an updated systematic review and meta‐analysis of the effects of CCTV on crime in public places. Evaluations were included if CCTV was the main intervention and the design was of high methodological quality. Forty‐four evaluations met the inclusion criteria. The results suggest that CCTV caused a modest (16%) but significant decrease in crime in experimental areas compared with control areas. This overall result was largely driven by the effectiveness of CCTV schemes in car parks, which caused a 51% decrease in crime. Schemes in most other public settings had small and nonsignificant effects on crime: a 7% decrease in city and town centers and in public housing communities. Public transport schemes had greater effects (a 23% decrease overall), but these were still nonsignificant. Schemes evaluated in the UK were more effective than schemes evaluated in the USA and other countries, but this was largely driven by the studies in the car parks. Implications for policy and research are discussed.

Ökonomische Überlegungen zur Kameraüberwachung als Maßnahme gegen den Terrorismus

In jüngster Zeit ist Kameraüberwachung als potenziell abschreckende Maßnahme bei der Bekämpfung von Kriminalität und Terrorismus zunehmend ins Blickfeld der Öffentlichkeit gerückt. Kameraüberwachung ist wohl das sich am schnellsten verbreitende Instrument und gleichzeitig eine der umstrittensten Maßnahmen heutiger Sicherheitspolitik. Diese Arbeit stellt theoretische Argumente und empirische Erkenntnisse vor, die es bei der Planung sowie auch bei methodisch anspruchsvollen Evaluationen zukünftiger Kameraüberwachungssysteme zu berücksichtigen gilt. Die bisherige Evidenz zeigt, dass die Wirksamkeit dieses Instruments bei der lokalen Prävention von Kriminalität stark kontextabhängig ist. Aufgrund einer vergleichenden ökonomischen Analyse illegalen Verhaltens erwarten wir eine relativ geringere abschreckende Wirkung von Kameraüberwachung auf Terrorismus als auf sonstige Formen der Kriminalität. Einerseits haben Terroristen viele Möglichkeiten, auf unüberwachte Ziele auszuweichen. Andererseits erhöhen Kamerabilder die Aufmerksamkeit, welche Terroristen erreichen können. <bold>Abstract</bold> In recent times, camera surveillance or closed-circuit television (CCTV) as an instrument potentially deterring crime and terrorism has become a focus of the public discourse. CCTV might be the most rapidly spreading and, at the same time, one of the most disputed measures of contemporary public security policy. This article presents theoretical arguments and empirical results that need to be considered in plans of future CCTV schemes as well as in methodically challenging CCTV evaluations. Previous evidence shows that the effectiveness of this situational crime prevention instrument is substantially depending on the context within which it is implemented. According to a comparative economic analysis of illegal behavior, we expect a relatively smaller deterrent effect of CCTV on terrorism than on other forms of crime. On the one hand, terrorists can switch to numerous alternative targets not monitored by cameras. On the other hand, CCTV images raise the degree of publicity terrorists can achieve. JEL Classifications: H56, K42

“Not the Usual Suspects”: A study of factors reducing the effectiveness of CCTV

Previous research on the effectiveness of Closed Circuit Television (CCTV) has focused on critically assessing police and government claims that CCTV is effective in reducing crime. This paper presents a field study that investigates the relationship between CCTV system design and the performance of operator tasks. We carried out structured observations and interviews with 13 managers and 38 operators at 13 CCTV control rooms. A number of failures were identified, including the poor configuration of technology, poor quality video recordings, and a lack of system integration. Stakeholder communication was poor, and there were too many cameras and too few operators. These failures have been previously identified by researchers; however, no design improvements have been made to control rooms in the last decade. We identify a number of measures to improve operator performance, and contribute a set of recommendations for security managers and practitioners.

Effects of Closed Circuit Television Surveillance on Crime

This Campbell systematic review examines the effects of closed circuit television (CCTV) on property crime and violent crime. The review reports on whether using CCTV results in crime displacement, and also assesses whether using CCTV leads to the spread of crime prevention benefits.The authors found 44 evaluations. The studies were from the United Kingdom, the United States of America, Canada, Norway and Sweden. Most of the studies (34) were from the United Kingdom.CCTV has a modest impact on crime. Effectiveness varies across settings. Surveillance is more effective at preventing crime in car parks, and less effective in city and town centers, public housing, and public transport. CCTV appears most effective in car parks at reducing vehicle crimes such as thefts from cars or stealing cars. The effectiveness of CCTV surveillance is greater when camera coverage of an area is high. CCTV surveillance does not have an effect on levels of violent crime.In all six of the CCTV car park studies, CCTV surveillance was an element in a broader package of crime prevention measures, such as extra security guards, better lighting, and fencing. It is not possible to assess the independent effects of each of these different components. The available evidence does not allow a conclusion as to whether CCTV leads to a displacement of crime or a diffusion of crime prevention benefits to other areas.AbstractBackgroundIn recent years, there has been a marked and sustained growth in the use of CCTV to prevent crime in public space in the U.K., United States, and other Western nations. In the U.K., CCTV is the single most heavily funded crime prevention measure operating outside of the criminal justice system. A key issue is how far funding for CCTV has been based on high quality scientific evidence demonstrating its efficacy in preventing crime. There is concern that this funding has been based partly on a handful of apparently successful schemes that were usually evaluated with less than rigorous designs, done with varying degrees of competence, and done with varying degrees of professional independence from government. Recent reviews that have examined the effectiveness of CCTV against crime have also noted the need for high quality, independent evaluation research.ObjectivesThe main objective of this review is to assess the available research evidence on the effects of CCTV surveillance cameras on crime in public space. In addition to assessing the overall impact of CCTV on crime, this review will also investigate in which settings, against which crimes, and under what conditions it is most effective.Search strategyFour search strategies were employed to identify studies meeting the criteria for inclusion in this review: (1) searches of electronic bibliographic databases; (2) searches of literature reviews on the effectiveness of CCTV in preventing crime; (3) searches of bibliographies of CCTV studies; and (4) contacts with leading researchers. Both published and unpublished reports were considered in the searches. Searches were international in scope and were not limited to the English language.Selection criteriaStudies that investigated the effects of CCTV on crime were included. For studies involving one or more other interventions, only those studies in which CCTV was the main intervention were included. Studies were included if they had, at a minimum, an evaluation design that involved before‐and‐after measures of crime in experimental and control areas. There needed to be at least one experimental area and one reasonably comparable control area.Data collection &amp; analysisNarrative findings are reported for the 44 studies included in this review. A meta‐analysis of 41 of these 44 studies was carried out; the requisite crime data was missing in other 3 studies. The “relative effect size” or RES (which can be interpreted as an incident rate ratio) was used to measure effect size. Results are reported for total crime and, where possible, property and violent crime categories using (mostly) official data. In the case of studies that measure the impact of CCTV programs on crime at multiple points in time, similar time periods before and after are compared (as far as possible). The review also reports on displacement of crime and diffusion of crime prevention benefits.Main resultsThe studies included in this systematic review indicate that CCTV has a modest but significant desirable effect on crime, is most effective in reducing crime in car parks, is most effective when targeted at vehicle crimes (largely a function of the successful car park schemes), and is more effective in reducing crime in the U.K. than in other countries.Reviewers’ conclusionsWe conclude that CCTV surveillance should continue to be used to prevent crime in public space, but that it be more narrowly targeted than its present use would indicate. Future CCTV schemes should employ high‐quality evaluation designs with long follow‐up periods.

Exploring The Teaching Of Nigerian University Undergraduates In Large Classes: The Perceived Effectiveness Of Closed-Circuit Television

Exploring The Teaching Of Nigerian University Undergraduates In Large Classes: The Perceived Effectiveness Of Closed-Circuit Television

The effects of closed-circuit television on crime: meta-analysis of an English national quasi-experimental multi-site evaluation

This article reports results obtained in an English national quasi-experimental multi-site evaluation of 14 closed-circuit television (CCTV) projects in residential areas, town and city centers, a city hospital, and car parks (parking lots). Both police and victimization data were collected before and after the installation of CCTV in target, control and buffer areas, and police Divisions. The results showed that CCTV was effective in reducing crimes in train station car parks but not in city centers or residential areas, seemed to be effective in reducing vehicle crimes (but not other types of crimes), and was most effective when the degree of coverage by CCTV was high and when CCTV was combined with other interventions such as improved lighting. Implications for situational crime prevention theory are drawn. There was no evidence of displacement or diffusion of benefits. It is concluded that CCTV needs to be implemented more effectively, based on an analysis of the crime problem and its causes, and needs to be evaluated using a randomized experimental design.

CCTV and Fight Against Retail Crime: Lessons from a National Evaluation in the U.K.

A review of the literature on the effectiveness of closed-circuit television (CCTV) suggests a mixed set of findings: sometimes it works, sometimes it does not, sometimes things may not change and often can appear to be worse. Part of the difficulty is that little is known about the way CCTV operates and how this might explain variations in findings. The study reported here was based on the evaluation of 13 (although one was split into two) publicly run CCTV systems set up across England. It focuses on a number of key aspects of the CCTV operation which influence the effectiveness of CCTV systems, including the management of implementation of the CCTV systems, the camera location and operation of the control room. This highlights how the operation of CCTV systems might be improved. It suggests that the lessons to be learned are important if CCTV is to be an effective tool in the fight against retail crime.

The role of technology in shaping CCTV surveillance practices

In the literature on the operation and effects of closed-circuit television (CCTV), attention has focused on the roles of human actors in surveillance practices. This article argues that, in addition, the role of technical artefacts in shaping surveillance should be taken into account. Through an empirical case study of centralized CCTV, the construction and operation of surveillance from the perspective of the technical, material design of the socio-technical network of video surveillance are explored. The analysis suggests that the application of complex technologies for camera surveillance does not simply augment but also limits the realization of targeted observations. This insight contributes to studies of CCTV and theories of surveillance concerned with analysing the surveillance capacities of contemporary surveillance practices.

Effects of Closed-Circuit Television on Crime

This article reports on the findings of a systematic review--incorporating meta-analytic techniques--of the available research evidence on the effects of closed-circuit television (CCTV) on crime in public space. A number of targeted and comprehensive searches of the published and unpublished literature and contacts with leading researchers produced twenty-two CCTV evaluations that met our criteria for inclusion in this review. CCTV had a significant desirable effect on crime, although the overall reduction in crime was a rather small 4 percent. All nine studies showing evidence of a desirable effect of CCTV on crime were carried out in the United Kingdom. Conversely, the other nine studies showing no evidence of any desirable effect of CCTV on crime included all five North American studies. CCTV was most effective in reducing crime in car parks. It had no effect on violent crimes but had a significant desirable effect on vehicle crimes.