Closed-circuit television (CCTV) (Part 2)

USES

Crime prevention

The two-year-old 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.

Marie Van Brittan Brown (October 30, 1922 – February 2, 1999) invented the home security system. The patent was granted in 1969. Brown was born in Queens, New York; she died there at age 76. Brown’s system had a set of 4 peep holes and a camera that could slide up and down to look at each one. Anything and everything the camera picked up would appear on a monitor. Also, a resident could unlatch the door by remote control. The system included a device that enabled a homeowner to use a television set to view the person at the door and hear the caller’s voice. She was given an Award from the National Scientist Committee.

A 2009 analysis by Northeastern University and the University of Cambridge, “Public Area CCTV and Crime Prevention: An Updated Systematic Review and Meta-Analysis,” examined 44 different studies that collectively surveyed areas from the United Kingdom to U.S. cities.
The analysis found that:

1.     Surveillance systems were most effective in parking lots, where their use resulted in a 51% decrease in crime;

2.     Public transportation areas saw a 23% decrease in crimes;

3.     Systems in public settings were the least effective, with just a 7% decrease in crimes overall. When sorted by country, however, systems in the United Kingdom accounted for the majority of the decrease; the drop in other  areas was insignificant.

 

The results from the above 2009 “Public Area CCTV and Crime Prevention: An Updated Systematic Review and Meta-Analysis”, are somewhat controversial. Earlier similar meta-analysis completed by Walsh and Farrington in 2002 showed similar results: a significant decrease in car parkcrime (41%), and a non-significant decrease of crime in public transit and public places. This study was criticized for the inclusion of confounding variables (e.g. notification of CCTV cameras on site, improved street lighting) found in the studies analyzed (including car park studies). These factors could not be differentiated from the effect of CCTV cameras being present or absent while crimes were being committed. Thus, a combination of factors might be important for the decrease in crime not just the CCTV cameras. The 2009 study admitted to similar problems as well as issues with the consistency of the percentage of area covered by CCTV cameras within the tested sites (e.g. car parks have more cameras per square inch than public transit). Another question in the effectiveness of CCTV for policing is around uptime of the system; in 2013 City of Philadelphia Auditor found that the $15M system was only operational 32% of the time. There is still much research to be done to determine the effectiveness of CCTV cameras on crime prevention before any conclusions can be drawn.

 

 

Closed-circuit video cameras in the Navy Yard complex caught gunman Aaron Alexis during his shooting rampage.

There is strong anecdotal evidence that CCTV aids in detection and conviction of offenders; indeed UK police forces routinely seek CCTV recordings after crimes. Moreover, CCTV has played a crucial role in tracing the movements of suspects or victims and is widely regarded by antiterrorist officers as a fundamental tool in tracking terrorist suspects. Large-scale CCTV installations have played a key part of the defences against terrorism since the 1970s. Cameras have also been installed on public transport in the hope of deterring crime, and in mobile police surveillance vehicles, often with automatic number plate recognition, and a network of APNI-linked cameras is used to manage London’s congestion charging zone. Even so, there is political hostility to surveillance and several commentators downplay the evidence of CCTV’s effectiveness, especially in the US. However, most of these assertions are based on poor methodology or imperfect comparisons.

 

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. 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. Critics however noted that benefits of non-monetary value cannot be captured in a traditional Cost Effectiveness Analysis and were omitted from their study. A 2008 Report by UK Police Chiefs concluded that only 3% of crimes were solved by CCTV. In London, a Metropolitan Police report showed that in 2008 only one crime was solved per 1000 cameras. In some cases CCTV cameras have become a target of attacks themselves.

 

Cities such as Manchester in the UK are using DVR -based technology to improve accessibility for crime prevention.

 

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”.

 

In 2013 Oaxaca hired deaf police officers to lip read conversations to uncover criminal conspiracies.

 

Source: Internet

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