Business Consultancy Services Ltd



Open letter


Andrew Potter

Chief Executive Officer

National Car Parks Limited
6th Floor
Centre Tower
Whitgift Centre
Croydon CR0 1LP 

17 August 2010

Dear Mr Potter

Biometrics – facial recognition and CCTV

I refer to the Daily Mail article[1] published on 7 August 2010, ‘Big Brother facial recognition cameras being rolled out in NCP car parks’.

Biometrics based on facial geometry have a long history of uninterrupted failure[2]. When the UK Passport Service[3] tested these biometrics back in 2006, 31% of able-bodied participants in the trial could not be recognised by the computer and, for the disabled, that figure rose to 52% – everyone would have done better to toss a coin.

Those were the failure rates about five minutes after the participants’ photographs were taken and registered on the database. According to the national Physical Laboratory[4], once a picture is more than two months old, “even under relatively good conditions, face recognition fails to approach the required performance”.

The UK Border Agency have been testing smart gates at airports to see if biometrics systems can match people to the photograph in their ePassport. UKBA have not published any results from their tests. The BBC[5] have, though, and so have the Daily Telegraph[6], [7], who found that in the opinion of one expert, this technology could not distinguish between Osama bin Laden and Winona Ryder.

The tests above have all been conducted using high quality cameras in well-lit areas with co-operative subjects. When it comes to CCTV in a car park, of course, or in a high street, the situation is quite different, as the police found in the London Borough of Newham[8] back in 1998:

Airport security isn't the only use for face-recognition software: it has been put through its paces in other settings, too. One example is “face in the crowd” on-street surveillance, made notorious by a trial in the London Borough of Newham. Since 1998, some of the borough's CCTV cameras have been feeding images to a face-recognition system supplied by Visionics, and Newham has been cited by the company as a success and a vision of the future of policing. But in June this year, the police admitted to The Guardian newspaper that the Newham system had never even matched the face of a person on the street to a photo in its database of known offenders, let alone led to an arrest.

1998 is a long time ago now. More recently, in 2007, the German federal police investigated facial recognition using CCTV. According to their report[9]:

The German Federal Criminal Police Office (BKA) found biometric visual-image search systems not advanced enough to be used by the police to search for persons. BKA presented research results of its visual-image search systems project. Given the present state of the technology the system was unfit to be deployed, they concluded.

BKA recommended that this is not a suitable system for surveillance and facial recognition to try to match suspects. The Federal Data Protection Commissioner Peter Schaar is warning against the use of an immature technology ...

The Commissioner also demanded legal safeguards against the linking of the image data recorded by surveillance cameras with the digital passport photographs stored in the passport and ID registers.

“... not advanced enough, ... unfit to be deployed, ... not a suitable system, ... immature technology, ...” – it is likely that the results of NCP’s trial will show that the technology doesn’t work well enough to increase security in car parks.

So what?

In that case, you could either thank the biometrics suppliers, recommend that they get the product right before wasting any more of NCP’s time and money, and keep the results quiet. Or you could perform a public service and publish your trial results through the Daily Mail, or whoever. That might stop the Home Office wasting any more of our money on this laughably unreliable technology. And that could mean good publicity for NCP and warm feelings for the brand from a grateful public.

Yours sincerely

David Moss

cc         Jaya Narain, Daily Mail