Sir - In response to your article Car crime rising, June 20, it seems the police are clutching at straws.

Since local police began campaigning for CCTV, the tide of public opinion has been turning against surveillance cameras in the UK. This has been in large part due to information coming to light which reveals that despite it having cost some £250m of public money its impact on crime prevention, detection and prosecution has been risible.

Earlier this month, the House of Commons Home Affairs Committee produced a report on the surveillance society in which a weight of evidence against CCTV was published. Most recently we have had the resignation of the Shadow Home Secretary David Davis MP over the slow strangulation of fundamental British freedoms by this government". Davis cited CCTV cameras in his resignation speech.

Now local police tell us that CCTV will magically cut car crime, where last year they said the cameras were needed to reduce violent crime.

The switch seems to be due to the fact that crime figures show violent crime on the Cowley Road to have fallen without cameras being installed. Perhaps another reason for the switch is the weight of evidence showing that CCTV has no effect on reducing violent crime but has a small effect in reducing car crime in car parks! Are local police suggesting that Cowley Road is a car park?

Perhaps local police would do well to listen to what the Thames Valley Police Assistant Chief Constable Gargan told the Home Affairs Committee's recent surveillance inquiry with regard to the effectiveness of CCTV: it is amazing how little impact they seem to have on the behaviour of all but a very few individuals who are very conscious of the cameras and play up to those cameras.

Charles Farrier, Oxford