Do Surveillance Cameras Reduce Crime?
Closed-Circuit TV (CCTV) cameras are being installing for
security purposes in record numbers by cities, businesses, and
The investment required for a surveillance camera can be
significant. Some of these cameras can
cost up to $50,000 each, and that is before the cost for human resources to
monitor the output is considered. J.P.
Freeman, a security market analyst company, projects that the
Public Debate Noise
Does the experience to date, demonstrate that security cameras can improve the public's safety?
Security Cameras are often politically controversial. This can result in the distortion of
facts. For example, a headline from a news article about a study conducted by the
The CITRUS study was very thorough and is frequently cited as evidence that surveillance cameras don't work, even though the study found significant positive effects from the cameras. However, because those results may not be consistent with the agenda, those results are often not reported.
Artificial Intelligence for Video Surveillance
Industry groups can also be guilty of bias, since they make their money from selling cameras. The newest technology in camera surveillance is the use of computers to interpret the data. This is a kind of artificial intelligence that is called "video analytics", and is potentially beneficial for efficient use of surveillance cameras, but this technology has sometimes been significantly oversold by the surveillance camera industry. This technology works best in less complex environments, such as a warehouse or loading dock that should be idle. Video analytics works much less well in busy environments like a crowd at a shopping mall.
"Some of the claims that are made are just
ridiculous," says Oliver Vellacott,
We have all seen the news reports about the 2005 London Terrorist bombings of the subways. Without the camera systems, where officials were able to track the movements of the perpetrators, it is very likely that it would have taken much longer to solve those crimes. It has been demonstrated many times that camera recording can be used to solve crimes. The Chicago Police Department estimates that the web of cameras installed in their city has been an important tool, resulting in more than 1,200 arrests since 2006. The Dallas Police Department has reported more than 1,700 arrests in a similar period from their camera system.
Video Analysis Automation with Human Oversight
Security systems works best when there is a system
observing the camera output. But human
time can be expensive, and this is where video analytics can be important. If a computer can screen many cameras, and
have the human review only the probable events, then a single human can monitor
many more cameras. It is also more
rewarding for the human not to watch camera output from eventless images. But we should keep our expectations realistic.
If we believed
Video Analytic systems are currently being installed in
Video Surveillance Proves Effective
Security cameras can be a deterrent to crime. In a study of convenience stores, CCTV showed impressive results. A sample of 81 stores were studied for 1 year before and and 1 year after the installation of CCTV camera security systems. The rate of robbery decreased by 53 percent after the cameras were installed.
The New York City Housing Authority estimates that the
CCTV systems have reduced crime by 36% in their public housing.
The conclusion is that a successful security camera
program requires more than just installing hardware. An effective program comprehends that a
camera that is not monitored, is a dumb piece of hardware, and the camera
system will lack credibility.