A report by the National Association for the Care and Resettlement of Offenders (Nacro) has cast doubt on CCTV's ability to cut crime.
Based on its research, Ms Rachel Armitage, of Nacro's crime and social policy unit, said: "It would be foolish to claim that well-planned CCTV can never have an impact, but the effectiveness of CCTV is often overstated."
Nacro's study said Home Office evaluations of 24 CCTV schemes in town centres, housing estates, public transport and car parks showed four had resulted in crime rates rising significantly.
A total of 13 resulted in a significant fall in crime, while seven had no effect.