Park your car. Walk into a store. Ride the subway. During all of these activities, it’s very likely that you are being recorded on video. In the western world, closed-circuit television or CCTV is used in the vast majority of public places to help prevent crime.
The idea is that video recordings can be used to look for potential perpetrators and that just knowing the cameras are there will deter people from committing crimes. But does CCTV really work?
One systematic review attempted to answer that question. The review, sponsored by the Campbell Collaboration, analyzed 44 studies that measured whether CCTV helped to reduce crime in parking lots, housing developments and on public transportation systems. It drew some interesting conclusions.
The researchers found that video surveillance systems were most effective in parking lots. Across the studies included in the analysis, CCTV resulted in a 51 percent decrease in crimes committed in parking lots.
CCTV resulted in a 23 percent decrease in crime on public transportation. However, in other public settings, CCTV yielded a small or no decrease in crime.
The authors did note some limitations in the data they used. Many of the studies did not specify whether there were signs indicating whether CCTV was used in the area, raising the question of whether it is more or less effective to notify the public about video surveillance. Other factors, including the quality of light and the percentage of areas covered by CCTV, are also important variables that many studies did not take into account.
More research is needed on this topic. But the evidence we have to date indicates that video surveillance is a useful tool for deterring crime.