That's also before you consider the trade off, both in privacy and in money. How much does it cost to put up all those cameras, and how far would that money go if applied to traditional law enforcement methods? Or just not spent because the cost still exceeds the benefit even if the benefit isn't statistically indistinguishable from zero?
That makes an impressive case for cameras. I would have expected a negative correlation. People put up more cameras where there are more crimes.
There is no reason to expect that correlation to exist. People put up cameras where they can afford to buy cameras and have a local legislature that can be influenced by contractors who want to sell cameras, but having money is inversely correlated with high crime rates.
There are more cameras in NYC than Detroit.
> A primary argument in favor of CCTV surveillance is improved law enforcement and crime prevention. We compared the number of public CCTV cameras with the crime and safety indices reported by Numbeo, which are based on surveys of that site’s visitors.
> For both indices, the correlation was weak (r = 0.168, r = -0.168, n = 120). A higher number of cameras just barely correlates with a higher safety index and lower crime index.