Lentis/Video Surveillance


Typical video surveillance camera

Public video surveillance commonly refers to closed-circuit television (CCTV). CCTV systems range from a simple mounted camera directly wired to a single computer screen, to smart systems with multiple cameras processing and synchronizing data from camera networks. In all systems the data is only broadcast to a private network or data source. Surveillance is used to monitor the actions of individuals or groups in order to protect them at a distance or to direct their behavior. Cameras are usually mounted in high-traffic, public areas where at least one party has security concerns.[1]


Early usage of CCTV is largely undocumented. Some attribute the first CCTV use to the German Army in World War II; however, the source is unconvincing. Video surveillance was limited in public spaces until video recording technology became more prevalent in the 1970s.[2] In 1987, the first video surveillance system of a downtown area in the UK was established in King’s Lynn.[3] By the 1990s and early 2000s, video surveillance systems could be seen in most major British and American cities. Current systems in many cities, such as New York City’s Lower Manhattan Security Initiative, use extensive camera networks to transmit live video data as part of counter-terrorism initiatives.[4][5] Great Britain is another major modern example of the use of mass surveillance to prevent crime and protect the public.

Advances in the fields of artificial intelligence and computer vision have made it possible to monitor video surveillance footage with a computer overseer[6]. This allows less people to monitor more cameras and can increase the effectiveness of camera monitoring. Software can identify faces in a video, track faces across multiple cameras, and classify people based on visual features. This technology has already been deployed in countries such as China. In the US, cities such as Detroit, Washington D.C, and Orlando are experimenting with it, meanwhile cities such as San Francisco and Oakland passed laws to ban government use of facial recognition.


It is estimated that one billion surveillance cameras will be deployed globally by 2021, with China accounting for more than 50% of the total. As of 2019, the United States and China have the largest camera to person ratio of roughly 1:4. A 50-70% increase in install based cameras was observed from 2018-2019. Chinese companies, Hangzhou Hikvision Digital Technology and Zhejiang Dahua Technology account for 38% of the market for install based cameras.[7] In the US, the motivation is to protect schools and malls. In China it's to monitor the public. India, Brazil, and Indonesia are quickly adopting CCTV technology as it becomes more affordable. India claims the system will "play a very vital role in improving outcomes in the area of criminal identification and verification."[8] In Singapore, residents feel that the cost of privacy associated with CCTV systems is worth the benefits of safety and security.


US common law holds that filming of persons in public places, even surreptitiously, does not constitute a violation of 4th amendment rights against unreasonable search and seizure. In Katz v. US (1967), the United States Supreme Court found no reasonable expectation of privacy in a public place.[9] This created the Katz test for legality of surveillance based on what a hypothetical objective person considers a “reasonable expectation” of privacy. The 9th Circuit Court has ruled “video surveillance does not in itself violate a reasonable expectation of privacy.”[10] Other federal courts have agreed[11], the Supreme Court has not directly ruled on video surveillance, and Congress has not passed any limiting laws.[12] On grounds of both statutory and case law, video surveillance of persons in public is legal in the US.

Due to federal regulation limiting audio surveillance in public, many surveillance systems only include video.[13] However, the 7th Circuit Court ruled in 2012 that audio recording of police in public is protected under the first amendment, and the US Supreme Court denied certiorari for an appeal.[14] Thus, the legality of audio surveillance may be changing, and video systems may begin including audio recording systems.

Observed EffectsEdit

CCTV cameras are often installed in areas in order to deter crime. One of the hopes is that the “halo effect” occurs where the crime rate is lowered both in areas observed by CCTV cameras and in areas nearby. On the other hand, some research demonstrates that crime is instead simply displaced to unmonitored areas. In some cases, while streets with security cameras installed did experience a decrease in reported crime, reported crime in neighboring streets increased.[15] In other areas, such as South Korea, the introduction of CCTV reduced crime rates significantly in monitored areas and slightly in neighboring areas but had no significant effect on crime rates in unmonitored areas. In this example, robbery and theft rates were observed to drop by 50% but there was not any measured drop in violent actions in monitored areas. [16] CCTVs can produce a false sense of security as people may feel safer in areas where cameras are present when in reality the cameras may not deter crime. Surveillance can also create a perceived increase in crime rates. As cameras are deployed in more areas, crimes are less likely to go undetected causing more crimes to be reported.[17]


The Panopticon is a disciplinary model in which an unseen overseer may, at any time, be monitoring those it oversees[18]. While under conspicuous video surveillance, participants are aware of the possibility that they are being observed but are usually unsure if anyone is actually watching. This causes participants to police themselves for fear of punishment should the overseer notice their bad behavior. This principle has been used in video surveillance applications ranging anywhere from terrorism prevention to traffic enforcement. This model can remain effective without any technology. For example, signs that indicate users are on camera do not require an actual video camera to instill fear.


NYC Domain Awareness SystemEdit

In the summer of 2012, New York City mayor Michael Bloomberg announced the “Domain Awareness System” (DAS): New York City’s new, extensive, integrated camera network and accompanying software. Through a partnership with Microsoft, NYC has joined existing public and private surveillance cameras, license plate cameras, and radiation detectors with data from emergency 911 calls and crime reports for crime prevention and solving.[19] The software can detect suspicious activity, like an unaccompanied package, and send data to police officers while police officers can input information, such as that of a stolen vehicle, and receive all locations of that vehicle within the last month.[20]

The DAS represents both the future of video surveillance and the surrounding debate. Most surveillance systems have been designed for a particular city, but Microsoft has begun marketing the DAS to other locations.[21] While New York City claims the system has already prevented crime, many parties have[22] questioned the validity of the DAS with respect to the 4th Amendment and racial profiling, including the ACLU and New York City Comptroller John Liu.[23]

Surveillance in ChinaEdit

In China, about 200 million private and public surveillance cameras monitor the population[24]. Additionally, China has begun to equip police officers with eyeglass cameras that can record footage and identify faces. China’s government has access to the footage from these cameras and uses it for a variety of applications.

The region of Xinjiang uses surveillance cameras to identify Uyghurs, an ethnic Muslim minority group native to northwest China, based on their facial characteristics[25]. China has used this information to discriminate against Uyghurs by tracking their movement and acting if they deem behavior unacceptable. China is known to have forcibly sent Uighurs to “re-education” camps in an attempt to make them loyal to the ruling party and "understand the dangers of religious extremism"[26].

China has also used this technology to curb jaywalking[27]. Cameras take photos of jaywalkers, use software and human overseers to find the names of the offenders, and display the photo and name on a billboard next to the crosswalk. Officials hope this will embarrass jaywalkers and prevent them from jaywalking again.

2019 Hong Kong ProtestsEdit

In 2019, citizens of Hong Kong protesting against a proposed extradition bill were concerned that they were being monitored with surveillance devices[28]. Some believed that China would use facial recognition software to identify protesters and take action against them. Protesters attempted to prevent monitoring by attacking photographers and tearing down “smart “lamp-posts equipped with traffic monitoring devices that Hong Kong’s government claims are not being used for surveillance purposes. They also used umbrellas and masks to hide their faces and prevent identification.

Piccadilly CircusEdit

In 2017, a large, 790 square meter billboard was installed in Piccadilly Circus in London[29]. What passersby do not see is the extensive array of video cameras hidden behind the display. They do not serve to prevent crime, but instead to target ads towards individuals who walk past. The cameras use facial recognition to identify the average age, gender, and mood of those in frame. They also track the make, model, and color of vehicles that drive by. Paired with the free Wi-Fi service from the billboard, this information is combined to determine the best advertisement to show at a given time. While this surveillance system can be used to reduce crime, its manifest function is for commercial use.

Employee SurveillanceEdit

TSA employees at the O'Hare International Airport are closely monitored with video surveillance. Employers are convinced that these systems improve employee productivity. In the restaurant waiting industry, revenue has increased due to surveillance.[30] However, employees try to avoid being watched and become much more passive to their management.[31] Studies show that this system increases stress, lowers job satisfaction, and prioritizes work quantity over quality.[32] This illustrates the displacement effect and psychological reactance towards video surveillance. Worker privacy is taken away and the reaction is to make it difficult to be managed by the employer. Furthermore, actions that would be considered unproductive are moved to areas where workers cannot be monitored.


Opponents of Video SurveillanceEdit

Graffiti artist Banksy in opposition to video surveillance

Opponents of video surveillance are mainly concerned with loss of privacy due to increasing camera presence and integration. Civil liberties groups, such as the American Civil Liberties Union, have campaigned against widespread CCTV use through opinion pieces and candidate support. The ACLU’s argument against surveillance focuses on four areas: ineffectiveness of the systems, potential abuse, lack of regulations and control of data, and the “effect on public life”.[33]

Other policy advocate and research groups, such as the Electronic Privacy Information Center (EPIC) and Big Brother Watch, focus solely on civil liberties and privacy, with an emphasis on public surveillance.[34][35] EPIC started an initiative in 2002 called “Observing Surveillance” that documents CCTV use in Washington D.C. and includes photo exhibits, public protests, and maps indicating surveillance cameras in tourist areas. Their goal is to “promote public debate” about the role of surveillance in a post-9/11 American society.[36] Many of these groups use similar tactics that compare societies with video surveillance to that in George Orwell’s 1984.[37] These tactics include street performances, where group members dressed as human CCTV cameras and read aloud from 1984 to demonstrate the comparison.[38]

Proponents of Video SurveillanceEdit

Surveillance footage used in finding Boston Marathon bombings suspect

Supporters of video surveillance contend that its role in preventing and solving crime outweighs its threats to privacy.

Crime PreventionEdit

A study conducted by the US Department of Justice (DOJ) examined the effectiveness of video surveillance systems in Baltimore, Maryland; Chicago, Illinois; and Washington D.C.[39] While the video surveillance systems in Baltimore and Chicago reduced crime by up 10%, with no significant crime displacement, the Washington D.C. system had no demonstrable effect on crime. Further, the DOJ showed that the benefits of reductions in crime in Baltimore and Chicago outweighed the costs of the surveillance system by as much as 4 to 1. However, video surveillance systems were not proven effective in all cases. In both Baltimore and Chicago, the crime rates in some areas of the cities were unaffected by increased video surveillance. Researchers suggest that the differences in effectiveness of surveillance systems could be partially explained by the system design, the public’s perception of and involvement in its implementation, and the degree to which the cameras are monitored by local law enforcement.

Solving CrimeEdit

Advocates argue that video surveillance is a valuable tool for solving crime. Video surveillance footage played a large part in the investigation of multiple high visibility terrorist attacks, including the 7/7 bombing in London in 2005 and the 2013 Boston Marathon Bombing. Boston street camera footage was used to identify the suspects and shared with the public 3 days after the bombing, sparking an unprecedented viral manhunt.[40] Public officials in Boston and across the US responded with increased support for public surveillance systems.[41] New York City mayor Michael Bloomberg spoke of video surveillance as a necessary reality in an increasingly dangerous world. On April 22, 2013 Bloomberg’s statements reflected an increasingly common sentiment: “the people who are worried about privacy have a legitimate worry…[but] we have to understand that in the world going forward, we’re going to have more cameras.”[42] While cameras were the key evidence needed for identifying the bombers, criticism of video surveillance arose from this event when users from social networking websites, Reddit and Twitter wrongly accused and harassed the family of innocent man, Sunil Tripathi.[43]

Public Opinion on Video SurveillanceEdit

Public support for video surveillance, like other forms of government surveillance, has remained relatively constant in recent years. 71% of those surveyed in a 2007 poll[44] supported increases in government video surveillance. A 2013 poll[45], conducted just weeks after the Boston Marathon Bombing, reported that 71% of respondents wanted to keep the same or increase the number of surveillance cameras (31% same, 40% increase) while only 12% wanted less video surveillance.

A pew research study found that 56% of adult Americans trust law enforcement to use facial recognition software coupled with video surveillance. Only 36% trusted technology companies to use facial recognition software and only 18% trusted advertisers.


Sousveillance, a term coined by Steve Mann, is defined as recording of an activity by disorganized citizens.[46] Where surveillance can be thought of as oversight, sousveillance is undersight. The etymology is French: 'sous' translates to 'from below' while 'sur' means 'over'. Sousveillance is possible as long as citizens have access to recording technologies.

Google Glass - an example of wearable sousveillance

Modern sousveillance has mostly taken the form of non-wearable devices. One billion cell phones were purchased worldwide in 2012, many of which contained a camera.[47] These cell phones have provided the public with an unprecedented ability to record video.

Wearable video recording technologies are also expanding. GoPro, a company producing wearable, high-definition video cameras, sold 2.3 million units in 2012.[48] Google has released 10,000 units of Google Glass, a camera and computer mounted on eyeglasses.[49] This technology offers users greater ability to discreetly and passively record video.

In cities where the majority of citizens use smartphones, there has been a rise in the use of sousveillance applications that allow citizens to share concerning events with each other and post pictures of incidents. In Stockholm, Sweden researchers found that the introduction of such applications increased the number of reports but had little effect on preventing crime.[50]Social networking sites like Facebook are being increasingly used for creating neighborhood watch groups where people use to share noteworthy information.


Rodney KingEdit

The 1991 videotaped beating of Rodney King by L.A.P.D. police officers represents an early, highly publicised example of sousveillance in the US. The video was captured with a personal video camera by a bystander observing the events from a nearby apartment. Following a heavily covered trial, the officers charged with the beating were acquitted, sparking the deadly 1992 Los Angeles riots.

UC Davis pepper-spray incidentEdit

The UC Davis pepper-spray incident refers to a 2011 incident in which students recorded a video of a riot geared police officer pepper-spraying non-violent protesters.[51] The incident received worldwide attention and prompted calls for resignation of the chancellor of the university.[52] This incident was a clear example of citizens using a video recording to challenge authority.


Sousveillance is supported by both popular media and police. Photography Is Not A Crime, a blog, documents cases of citizens dissuaded from filming police. It holds that filming of persons in public has never been illegal and reports on purported violations of this right.[53] Head-mounted cameras on police officers are a mix of surveillance and sousveillance: The recording is from a participant’s perspective but is kept by authorities. A year-long experiment in Rialto, California showed that recording police interactions caused a drastic drop in complaints against officers during arrests and sometimes helped prove officer wrongdoing.[54] Sousveillance of police has also be implemented in requiring police officer to wear body cameras while on duty. For the Las Vegas police department, the use of body cameras lead to a 37% reduction in the use of force by officers and a 30% decrease in officers with at least one complaint against them. [55]


Prevalence of citizen-owned video recording devices may pose a risk to privacy separate from surveillance by governments or corporations. Universal internet connectivity allows easy video dissemination through social media. Facial recognition technology, already employed by private surveillance entities, can further erode privacy and anonymity. A letter from Senator Al Franken to the National Telecommunications and Information Administration regarding facial recognition technology reveals a public concern for privacy.[56] The Obama administration has tasked the NTIA with researching facial recognition technology.[57] Companies have taken steps to combat privacy violations by sousveillance. In Japan, cell phone camera shutter sounds cannot be disabled to discourage discrete photography.[49] Google has banned all facial recognition apps on Google Glass.[58]


Both video surveillance and sousveillance have become fixtures of modern society, proving to be valuable tools for deterring crime and police misconduct while also creating privacy concerns. Advocacy groups have emerged on both sides of the issues. While it remains unclear whether sousveillance or surveillance will become most relevant to privacy concerns, it is certain that the status quo is changing. Citizens’ perceptions and expectations of privacy shape how technology is used, but that same technology affects the socially evolving expectations of privacy.

Further ResearchEdit

Ideas for future research and expansion of this chapter include

  • Lifeloggers - Those who record their lives with wearable cameras; an idea pioneered by Steve Mann
  • Leon Rosby - Hawthorne man arrested after filming policemen. His arrest was recorded as well by two other bystanders.
  • Google street view and privacy
  • Dashcams


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