Silent witness: The rise of CCTV and the fall of privacy

CCTV cameras have proved very useful in criminal investigations, but their role in surveillance is more controversial. What of our privacy, wonders Penny Lewis, and when is their use justifiable?

Who will forget the pictures of the toddler James Bulger being led away from a shopping centre by Robert Thomson and Jon Venables? Or late-night images of Ealing High Street being devastated by an IRA bomb? In the aftermath of serious crimes such as these, police access to contemporaneous film footage provides crucial clues in their forensic investigations.

It is one thing for such evidence to find its way into court as a vital tool of the criminal justice system, but what legal limits are there on its use in general to prevent ordinary people being spied on unjustifiably? A House of Lords Select Committee on Science and Technology has said that if public confidence in CCTV systems is to be maintained there needs to be tighter control over its use.

We are now accustomed to the electronic eyes that monitor roads nationwide, surveying traffic flow and catching drivers who break the law. Recently, many of the ubiquitous grey metal speed cameras have been painted a vivid yellow, following criticism that cameras were surreptitiously placed, often behind a tree or street sign.

The newly named Department for Transport (DfT) says that the changes have been carried out as part of a voluntary scheme and are prompted by "safety concerns". Twenty nine out of 43 police areas have opted to give the equipment a makeover to ensure that cameras are "more visible" and "to encourage motorists to slow down". It was feared too that motorists who only saw the deterrent at the last second would brake suddenly, precipitating an accident. Many of us have done this. The DfT is keen to describe the equipment as safety cameras, not surveillance cameras. Nevertheless, as David Sonn, a specialist criminal lawyer, points out: "It is real evidence and is admissible in criminal proceedings."

If your vehicle is captured on camera as having exceeded the speed limit the magistrates' court will send a notice to the address of the registered keeper informing them of prosecution. If charges are brought but someone else was driving, Sonn explains that "as with all evidence, the defendant is entitled to be given access to it since it might reveal who was driving the vehicle".

Peter Lodder QC adds that "as a general rule all evidence is admissible but certain types of evidence can be objected to, such as if it is 'hearsay'." The quality and content of the images are also important. He gives an example of a defendant who says that "he doesn't have blue jeans" whereas the individual on camera is sporting Levis. This apparent discrepancy "goes to the weight of the evidence".

Thames Valley information technology lawyer Mark Blunden cautions that "CCTV footage falls within the provisions of the Data Protection Act 1998". Surprisingly, this legislation provided the first meaningful legal framework for the regulation of camera surveillance when it was brought into force in March 2000. The Act governs the manner in which personal data – including photographic images – can be obtained, stored and passed on. The technical term for this series of acts is processing. Breach of the act is a criminal offence.

Under the Data Protection Act, the Information Commissioner is allowed to lay down codes of conduct, intended to represent best practice in a particular field. The first such directive to be issued, and as Blunden points out before the implementation of the Human Rights Act 1998, contained detailed guidelines concerning CCTV surveillance. It does not regulate security cameras in the home or by criminal-investigation agencies.

The document sets out comprehensive recommendations that cover every aspect of camera use, from where they should be sited to how long material can continue to be used. The basic principle is that there must be a "legitimate basis" for processing. This means conducting an assessment of the purpose for which cameras are installed – and not using them for any other reason. Therefore, while CCTV cameras belonging to a council fulfil a justifiable role in monitoring premises such as a shopping mall or municipal car park, video recordings should only be used to support a criminal enquiry and not supplied to a third party such as a newspaper for an unrelated commercial purpose. Users are urged to record the reasons that the equipment has been installed.

How long film should be retained is also regulated. For example, it is recommended that publicans ought not keep it for more than seven days unless it is needed for a specific purpose. The rationale is that managers would by then be aware of any incident and the need to retain evidence.

According to Blunden, one potential legal hot potato is when cameras have access to public spaces. CCTV located on public property might also be trained partly on to private premises. Here, the camera user may fall foul of the Information Commissioner's enforcement powers. The code advises that if there is a danger of equipment recording, say, a private residence, that affected people are consulted.

Another important thing to remember, says Blunden, is that the code also requires users to "have a notice warning of CCTV operation if it is being used in a public place". There are two elements to the notice: first, the need to draw attention to the existence of the system; and, second, to explain the function. Failure to alert the public to the presence of cameras can have serious repercussions. If a notice in a car park says that CCTV is in operation to prevent theft, then can film be used to trace and prosecute someone who commits a sexual offence? A spokesman from the Information Commission says that they would adopt "a common-sense approach. It is about proportionality". The office says that a new, updated code will be on the agenda.

There is little doubt that film footage plays an important part in the apprehension and successful prosecution of offenders. Participants in riots as well as those who commit shoplifting offences, car and street robberies can sometimes be identified by comparison of photographic evidence with celluloid images.

But what about breach of privacy? Peter Lodder QC says that it is difficult for people to complain about being caught on camera in a public place because "you are outside your home so there is no argument based on privacy". Is it a defence in criminal proceedings to argue that the filming was covert? Lodder confirms that "entrapment is not a defence". However, that the police have painted speed cameras yellow suggests a sensitivity on this issue.