Police stops on Essex Rd

What I want to know is, if the Police are taking all this DNA, stopping and searching all these people, and there's all this CCTV everywhere, how come shit load of crime goes on and the perpetrators are rarely caught?

CCTV is ineffective as a crime prevention tool.

The Home Office's own study on CCTV (292 - 2005) says that CCTV is not effective, the majority of schemes evaluated did not reduce crime and even where there was a reduction in crime that was mostly not due to CCTV, nor do CCTV schemes make people feel safer, much less change their behaviour.