A really interesting map on the website of the US monthly, The Atlantic, illustrating the relationship between density of video surveillance cameras (CCTV) and recent incidence of rioting in London. There are many things one can get even from a simple map like this. It’s worth noting in particular that Wandsworth and Harringey are the residential boroughs with the highest concentration of CCTV, and have been hit by rioting. There are also places with both greater and less than average density of CCTV which have not had rioting.
Whilst you have to be careful not to mistake correlation for causality, and bearing in mind that this is not a statistically tested verdict, the main tentative conclusion one can draw is that there seems to be no relationship between the presence and density of CCTV and the occurence of rioting. This might seem like a fairly weak statement, but it is yet more evidence that CCTV has little deterrent effect on crime of this sort (and of course, the rioting is not only explicable as ‘crime’ anyway).