A short video.

Do CCTV cameras prevent crime?
"... most systems revealed little overall effect on crime levels ..." The impact of CCTV: fourteencase studies. Home Office Online Report 15/05 (www.homeoffice.gov.uk/rds/pdfs05/rdsolr1505.pdf).

Do CCTV cameras help solve crime?
"Only 3% of street robberies in London were solved using CCTV images ..." Detective Chief Inspector Mick Neville (www.guardian.co.uk/uk/2008/may/06/ukcrime1)

How much has been spent on CCTV systems?
"Billions of pounds has been spent on kit ..."
Detective Chief Inspector Mick Neville (www.guardian.co.uk/uk/2008/may/06/ukcrime1)

A quote from a reply by "Amon"