Editing Closed-circuit television (section)

=== Crime prevention ===
[[File:Bulger cctv.jpg|thumb|The two-year-old [[Murder of James Bulger|James Bulger]] being led away by his killers, recorded on shopping centre CCTV in 1993; this [[narrow-bandwidth television]] system had a low [[frame rate]]]]
[[File:Video surveillance sign.jpg|thumb|Sign warning that premises are watched by CCTV cameras]]
{{further|crime prevention|predictive policing|criminal investigation}}

A 2008 report by UK Police Chiefs concluded that only 3% of crimes were solved by CCTV.<ref>[http://forward-edge.net/the-big-question-are-cctv-cameras-a-waste-of-money-in-the-fight-against-crime-822079.html "Are CCTV cameras a waste of money in the fight against crime?"] {{Webarchive|url=https://web.archive.org/web/20160304061337/http://www.forward-edge.net/the-big-question-are-cctv-cameras-a-waste-of-money-in-the-fight-against-crime-822079.html|date=4 March 2016}} Forward Edge, 7 May 2008</ref> In London, a [[Metropolitan Police]] report showed that in 2008 only one crime was solved per 1000 cameras.<ref>{{cite news |last=Hughe |first=Mark |date=25 August 2009 |title=CCTV in the spotlight: one crime solved for every 1,000 cameras |url=https://www.independent.co.uk/news/uk/crime/cctv-in-the-spotlight-one-crime-solved-for-every-1000-cameras-1776774.html |publisher=Independent News and Media Limited}}</ref> In some cases CCTV cameras have become a target of attacks themselves.<ref>"[http://news.bbc.co.uk/1/hi/wales/south_east/3676550.stm http://news.bbc.co.uk/]" BBC</ref> A 2009 systematic review by researchers from [[Northeastern University]] and the [[University of Cambridge]] used [[meta-analysis|meta-analytic]] techniques to pool the average effect of CCTV on crime across 41 different studies.<ref name="Public">{{cite web|url = http://journalistsresource.org/studies/economics/housing/surveillance-cameras-and-crime/ |title = Public Area CCTV and Crime Prevention: An Updated Systematic Review and Meta-Analysis |publisher = Journalist's Resource.org |date = 11 February 2014 }}</ref> The studies included in the meta-analysis used [[quasi-experiment|quasi-experimental evaluation designs]] that involved before-and-after measures of crime in experimental and control areas.<ref name="Public" /> However, researchers have argued that the British car park studies included in the meta-analysis cannot accurately control for the fact that CCTV was introduced simultaneously with a range of other security-related measures.<ref>{{Cite journal|title = The economics of subjective security and camera surveillance|url = https://wwz.unibas.ch/fileadmin/wwz/redaktion/wipo/Alois_Stutzer/Zehnder_B-099.pdf |date = 2009|last = Zehnder|journal = WWZ Research Paper|access-date = 27 October 2017|archive-url = https://web.archive.org/web/20170706060053/https://wwz.unibas.ch/fileadmin/wwz/redaktion/wipo/Alois_Stutzer/Zehnder_B-099.pdf|archive-date = 6 July 2017|url-status = dead}}</ref> Second, some have noted that, in many of the studies, there may be issues with [[selection bias]] since the introduction of CCTV was potentially [[Endogeneity (econometrics)|endogenous]] to previous crime trends.<ref>{{Cite journal|title = The Effects of Surveillance Cameras on Crime: Evidence from the Stockholm Subway|journal = The Economic Journal|date = 1 November 2015|issn = 1468-0297|pages = F289–F305|volume = 125|issue = 588|doi = 10.1111/ecoj.12327|first = Mikael|last = Priks|s2cid = 96452277}}</ref> In particular, the estimated effects may be biased if CCTV is introduced in response to crime trends.<ref>{{Cite journal|title = Is camera surveillance an effective measure of counterterrorism?|journal = Defence and Peace Economics|date = 2013|pages = 1–14|volume = 24|doi = 10.1080/10242694.2011.650481|last = Stutzer|doi-access = free}}</ref>

[[File:Alexis Navy Yard 012 1dsLQLVk7nY.jpg|thumb|A CCTV captured the perpetrator of the [[Washington Navy Yard shooting]], Aaron Alexis, during his rampage]]
In 2012, cities such as Manchester in the UK are using [[Digital video recorder|DVR]]-based technology to improve accessibility for crime prevention.<ref>{{Cite news |date=2002-06-28 |title=Digital CCTV scheme switches on |url=http://news.bbc.co.uk/2/hi/uk_news/england/2070312.stm |access-date=2024-12-21 |work=BBC News |language=en-GB}}</ref> In 2013, City of Philadelphia Auditor found that the $15 million system was operational only 32% of the time.<ref>{{cite web|url=http://www.viakoo.com/orphaned-video-system-in-philadelphia/|title=Orphaned Video System in Philadelphia?|date=May 2015|access-date=29 July 2015|archive-date=28 October 2017|archive-url=https://web.archive.org/web/20171028042359/https://www.viakoo.com/orphaned-video-system-in-philadelphia/|url-status=dead}}</ref> There is [[anecdotal evidence]] that CCTV aids in detection and conviction of offenders; for example, UK police forces routinely seek CCTV recordings after crimes.<ref>[https://www.telegraph.co.uk/news/uknews/crime/10512087/10484338Police-are-failing-to-recover-crucial-CCTV-footage-new-figures-suggest.html?fbHow&goback=%2Egde_1889337_member_5817222616544473092 "Police are failing to recover crucial CCTV footage, new figures suggest"], The Daily Telegraph</ref> Cameras have also been installed on [[public transport]] in the hope of deterring crime.<ref>{{Cite news |date=2003-09-11 |title=CCTV to drive down cab attacks |url=http://news.bbc.co.uk/2/hi/uk_news/england/hereford/worcs/3101016.stm |access-date=2024-12-19 |language=en-GB}}</ref><ref>{{Cite news |date=2005-02-25 |title=Taxi CCTV cameras are installed |url=http://news.bbc.co.uk/2/hi/uk_news/england/bristol/somerset/4295859.stm |access-date=2024-12-19 |language=en-GB}}</ref>

A 2017 review published in the [[Journal of Scandinavian Studies in Criminology and Crime Prevention]] compiles seven studies that use such research designs. The studies found that CCTV reduced crime by 24–28% in public streets and urban subway stations. It also found that CCTV could decrease unruly behaviour in football stadiums and theft in supermarkets/mass merchant stores. However, there was no evidence of CCTV having desirable effects in parking facilities or suburban subway stations. Furthermore, the review indicates that CCTV is more effective in preventing property crimes than in violent crimes.<ref>{{Cite journal |author=Gustav Alexandrie |date=2017 |title=Surveillance cameras and crime: a review of randomized and natural experiments |journal=Journal of Scandinavian Studies in Criminology and Crime Prevention |volume=18 |issue=2 |pages=210–222 |doi=10.1080/14043858.2017.1387410 |s2cid=149144413}}</ref> However, a 2019, 40-year-long [[systematic review]] study reported that the most consistent effects of crime reduction of CCTV were in car parks.<ref>{{Cite journal |last1=Piza |first1=Eric L. |last2=Welsh |first2=Brandon C. |last3=Farrington |first3=David P. |last4=Thomas |first4=Amanda L. |date=2019 |title=CCTV surveillance for crime prevention: A 40-year systematic review with meta-analysis |url=https://onlinelibrary.wiley.com/doi/10.1111/1745-9133.12419 |journal=Criminology & Public Policy |language=en |volume=18 |issue=1 |pages=135–159 |doi=10.1111/1745-9133.12419 |issn=1538-6473}}</ref>

A more open question is whether most CCTV is cost-effective. While low-quality domestic kits are cheap, the professional installation and maintenance of high definition CCTV is expensive.<ref>{{cite web |url=http://www.allthings.com.au/Catalogue/cctv%20security%20surveillance%20ip%20network%20dome%20camera%20articles/Tip%20Sheet%205.pdf |title=National community Crime Prevention Programme |access-date=2016-03-30 |archive-url=https://web.archive.org/web/20160229022046/http://www.allthings.com.au/Catalogue/cctv%20security%20surveillance%20ip%20network%20dome%20camera%20articles/Tip%20Sheet%205.pdf |archive-date=29 February 2016 |url-status=dead}}</ref> Gill and Spriggs did a [[cost-effectiveness analysis]] (CEA) of CCTV in crime prevention that showed little monetary saving with the installation of CCTV as most of the crimes prevented resulted in little monetary loss.<ref name="Assessing">{{cite web |url=http://rds.homeoffice.gov.uk/rds/pdfs05/rdsolr1205.pdf |archive-url=http://webarchive.nationalarchives.gov.uk/20110218135832/http://rds.homeoffice.gov.uk/rds/pdfs05/rdsolr1205.pdf |url-status=dead |archive-date=2011-02-18 |title=Assessing the impact of CCTV |access-date=2011-10-16}}</ref> Critics however noted that benefits of non-monetary value cannot be captured in a traditional cost effectiveness analysis and were omitted from their study.<ref name="Assessing" />

In October 2009, an "Internet Eyes" website was announced which would pay members of the public to view CCTV camera images from their homes and report any crimes they witnessed. The site aimed to add "more eyes" to cameras which might be insufficiently monitored. Civil liberties campaigners criticized the idea as "a distasteful and a worrying development".<ref>[http://news.bbc.co.uk/1/hi/england/london/8293784.stm Public to Monitor CCTV From Home], ''[[BBC]]''</ref> Russia has also implemented a video surveillance system called 'Safe City', which has the capability to recognize facial features and moving objects, sending the data automatically to government authorities. However, the widespread tracking of individuals through video surveillance has raised significant privacy issues.<ref>Artificial intelligence in local government services: Public perceptions from Australia and Hong Kong, Government Information Quarterly, Volume 40, Issue 3, June 2023, 101833</ref>

==== Forensics ====
Material collected by surveillance cameras has been used as a tool in post-event forensics to identify tactics and perpetrators of [[terrorist attack]]s. Furthermore, there are various projects—such as [[INDECT]]—that aim to detect suspicious behaviours of individuals and crowds.<ref>{{cite journal |last1=Mould |first1=Nick |last2=Regens |first2=James L. |last3=Jensen |first3=Carl J. |last4=Edger |first4=David N. |date=30 August 2014 |title=Video surveillance and counterterrorism: the application of suspicious activity recognition in visual surveillance systems to counterterrorism |journal=Journal of Policing, Intelligence and Counter Terrorism |volume=9 |issue=2 |pages=151–175 |doi=10.1080/18335330.2014.940819 |s2cid=62710484}}</ref> It has been argued that terrorists will not be deterred by cameras, that terror attacks are not really the subject of the current use of video surveillance and that terrorists might even see it as an extra channel for [[propaganda]] and publication of their acts.<ref>{{cite magazine |date=10 May 2010 |title=In the Petabyte Age of Surveillance, Software Polices |url=http://www.popularmechanics.com/technology/security/how-to/a5776/surveillance-cameras-and-data/ |access-date=4 January 2017 |magazine=Popular Mechanics}}</ref><ref>{{cite web |date=26 October 2016 |title=Mehr Videoüberwachung gegen Terroristen - WDR aktuell - Sendung - Video - Mediathek - WDR |url=http://www1.wdr.de/mediathek/video/sendungen/wdr-aktuell/video-mehr-videoueberwachung-gegen-terroristen-100.html |access-date=4 January 2017 |publisher=WDR}}</ref> In Germany, calls for extended video surveillance by the country's main political parties, [[Social Democratic Party of Germany|SPD]], [[Christian Democratic Union of Germany|CDU]], and [[Christian Social Union in Bavaria|CSU]] have been dismissed as "little more than a [[placebo]] for a subjective feeling of security" by a member of the Left party.<ref>{{cite web |title=Calls increase for sweeping surveillance after Berlin attack |url=http://www.dw.com/en/calls-increase-for-sweeping-surveillance-after-berlin-attack/a-36854715 |access-date=4 January 2017 |publisher=Deutsche Welle}}</ref>

In Singapore, since 2012, thousands of CCTV cameras have helped deter [[loan shark]]s, nab litterbugs, and stop illegal parking, according to government figures.<ref>{{Cite web |date=8 March 2016 |title=Network of CCTV cameras proving effective |url=http://www.straitstimes.com/singapore/network-of-cctv-cameras-proving-effective |access-date=2017-02-06 |publisher=straitstimes}}</ref> In 2013, [[Oaxaca]], Mexico, hired deaf police officers to [[lip reading|lip read]] conversations to uncover criminal conspiracies.<ref>{{Cite web |last=Maria Alvarez |first=Jose |date=November 20, 2013 |title=Mexico's Angels of Silence: Deaf police officers see crime where others don't |url=http://m.theglobeandmail.com/news/world/oaxacas-angels-of-silence-deaf-police-officers-see-crime-where-others-dont/article15520263/?service=mobile |url-status=dead |archive-url=https://archive.today/20131121124759/http://m.theglobeandmail.com/news/world/oaxacas-angels-of-silence-deaf-police-officers-see-crime-where-others-dont/article15520263/?service=mobile#selection-101.1-101.78 |archive-date=21 November 2013 |website=Globe & Mail}}</ref>
[[File:Omar Habhan Westgate attack.webp|thumb|[[Omar Nabhan]], as seen on CCTV during the [[Westgate shopping mall attack]] that resulted in the deaths of 71 people. Authorities observed the attack via the cameras within the mall.]]