BBC Scotland's Rob Flett reports

Professor James Ditton, of the Scottish Centre for Criminology, says the cameras have not lived up to their early promise.

After four years of monitoring the monitors, the professor, who led a Scottish Office study into CCTV, has called for an independent watchdog to oversee the use of the technology.

The centre of Glasgow alone is screened day and night by 32 cameras.

CCTV has "some value" for the police

"It has been overhyped and I think that is one of the problems," Prof Ditton told BBC Scotland.

"It was allegedly going to give us these magnificent benefits of reducing crime and making the fear of crime diminish to almost nothing.

"Although it probably does have some utility for the police it does not have these wonderful great societal benefits, so we really question whether the benefits it does bring us justify photographing everybody who goes into the city everyday."

Professor James Ditton: "The cameras were vastly overhyped."

He argued that since the Glasgow cameras were switched on in 1994 crime had fallen more sharply elsewhere than under their gaze.

He said street surveys had shown people do not feel any safer now.

Professor Ditton also said the cameras had not proved cost effective, producing just one arrest every 40 days.

"We were very surprised by the findings. We had done some previous research in Airdrie where CCTV started in Scotland and where we found there was quite a significant fall in crime after the installation of the cameras," he said.

Systems have been "over-hyped"

"To be honest, we expected to find the same in the Glasgow and we were very surprised to find it didn't really happen."

The report said there had been no sign of the investment, jobs or visitors it was promised the cameras would generate.

But because CCTV systems are spreading across the country and some have a wide focus, the professor is advocating the creation of an independent watchdog to monitor the way the cameras are used.

'Vastly overhyped

He said people may begin to question whether they want the police secretly to tape them in public.

"The cameras were so vastly overhyped as a magic bullet cure for everything when they were introduced, that we were all blinded to the fact that this was a small addition in police terms, but a rather large incursion in civil liberty terms," said Professor Ditton.

Edinburgh city centre CCTV operator Gary Ogilvie responded to the report by insisting on the benefits of the system.

BBC's Maggie Shields reports on reactions from the public

Mr Ogilvie said: "The cameras can cover large areas very quickly.

"We are identifying things which we can get the police travelling to quickly.

"In Edinburgh we have an excellent relationship with the police and we get very good response times.

"This is something the business community in Edinburgh has commented upon - that response times to incidents since CCTV went in have been much improved," he added.

But a Scottish Executive spokesman said while the government was disappointed with the figures in the research, it still believed CCTV made a significant contribution to cutting crime.

"The Scottish Executive believes that the majority of CCTV schemes help to prevent crime and allay public concerns," he said.