Existing Literature
Given the controversial nature of CCTV, surprisingly little is known about how it is used and how effective it is in achieving many stated aims. CCTV has several potential applications for public safety, and has been deployed with the intention variously of preventing crime, detecting offences, improving the response to emergencies, assisting in the management of places and reducing public fear of crime (Ratcliffe 2011, p 15). CCTV can also be used for purposes not related to public safety, such as monitoring transport-passenger flows and investigating complaints against facility staff (National Rail CCTV Steering Group 2010, p 7).
Of these potential applications, almost all research attention to date has concentrated on the use of CCTV to prevent crime (Honovich 2008). Early studies by Mayhew et al. (1979) and Webb and Laycock (1992) suggested that CCTV was effective at reducing robberies at London Underground stations, although the evaluation methods used had some limitations. Since then, the subject has received substantial research attention with mixed empirical results. For example, several evaluations have found CCTV to be effective at reducing thefts in car parks (Poyner and Webb 1987; Tilley 1993) but others have shown it to have little or no impact on crime in residential areas (Gill and Spriggs 2005). A systematic review by Welsh and Farrington (2008) of 41 studies concluded that CCTV is effective at preventing some types of crime in some circumstances, but that the evidence suggests it has a more limited impact than its widespread deployment may suggest. In contrast to the extensive literature on the value of CCTV for crime prevention, there is little research on how useful cameras are for other purposes. Ditton and Short (1998) found that in the 2 years after the installation of a CCTV scheme in a Scottish town, the proportion of crimes that were solved by police increased from 50 to 58%, with some offences showing larger increases than others. However, no information was given about whether these changes were statistically significant, and rates were only provided for some types of crime (the primary focus of the study was on crime prevention).
In Australia, Wells et al. (2006) found that monitored CCTV in two suburbs led to the early arrest of a small number of offenders at the scenes of crimes, but did not look at whether recordings were useful in
the subsequent investigations. Limited evidence can be found in research on solvability factors: the features of an offence that determine the likelihood of the case being solved. Paine (2012) found CCTV
to not be associated with higher detection rates for residential burglary. For non-residential burglary, Coupe and Kaur (2005) found that CCTV being installed in a building was associated with double the rate of detections compared to other buildings, driven by the increased availability of suspect descriptions. Since this study used data from the year 2000, it is possible that subsequent developments in technology may have influenced the effectiveness of CCTV in solving this type of crime. For example, modern cameras are likely to provide higher-resolution images, and digital (as compared to tape-based) storage allows images to be retained for longer (Taylor and Gill 2014). Existing research on solvability factors is limited because it is largely focused on the investigation of a single crime type (burglary).
In the context of this limited academic evidence, several organizations have produced reports on the topic of the value of CCTV for investigation, some of dubious quality. For example, Davenport (2007) summarized an unpublished report by the Liberal Democrat political party which concluded that CCTV cameras were ineffective simply because London boroughs with more cameras did not have a higher all-crime detection rate. The group appeared to have made no attempt to control for confounding variables or for different types of crime. Despite the poor quality of the analysis, this report has subsequently been cited in the media (e.g. by Bates 2008) as proof that CCTV is ineffective in investigations. Journalists have also carried out their own analyses. Staff from The Scotsman (2008) newspaper reported that in a 4-year period CCTV cameras in Scotland had observed more than 200,000 incidents, with responding police officers making arrests in 14% of cases. However, no details were given on whether those arrests led to charges, whether further suspects were identified later or how the headline statistic varied in different circumstances or for different types of crime. In San Francisco, journalists found that cameras had given detectives new avenues of investigation in seven of 33 violent felonies committed in a crime hotspot over a 2-year period (Bulwa and Stannard 2007).
Meanwhile the London Borough of Hackney (2016) reported that over a 12-year period the use of CCTV had been associated with more than 27,000 arrests, although it gave no further details. Edwards (2009) reported that CCTV evidence was gathered in 86 of 90 murder investigations and was judged by
senior police officers to have been valuable in 65 of those cases. There appears to be some disagreement within the police service as to how effective CCTV cameras are in criminal investigations. Several news outlets summarized a report from the London Metropolitan Police Service (MPS) that appeared to be highly critical of its usefulness. Bowcott (2008) reported that “only 3% of street robberies in London were solved using CCTV images”, although other articles reported that the 3% statistic applied to all crime (e.g. Johnson 2008). In another article based on the same report, Edwards (2008) wrote that “up to 80 per cent of CCTV footage seized by police is of such poor quality that it is almost worthless for detecting crimes”. Hickley (2009) quoted a police spokesperson as saying that “in 2008 less than 1,000 crimes were solved using CCTV despite there being in excess of one million cameras in London”. However, to the present author’s knowledge, the report itself remains unpublished and no information is available on the methods used, nor any more details of the conclusions.
In contrast, the majority of British officers surveyed by Levesley and Martin (2005) believed that CCTV was a useful investigative tool. A report on the value of CCTV commissioned by Dyfed-Powys Police in Wales argued that cameras were valuable in the detection of crime, citing the opinions of police investigators and local prosecutors. However, the report also recommended that live-monitoring of CCTV cease because it was ineffective at preventing crime or improving the initial response to incidents (Instrom Security Consultants 2014). Several municipalities in Britain have decreased their investment in CCTV in response to recent budget cuts (Merrick and Duggan 2013).
Overall, little appears to be known about how the usefulness of CCTV for investigation varies across crime types or circumstances, which is likely to be important in any attempts to make CCTV more useful. The present exploratory study attempted to provide some evidence in these areas.
source : https://www.researchgate.net/publication/316344070_The_Value_of_CCTV_Surveillance_Cameras_as_an_Investigative_Tool_An_Empirical_Analysis
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