When you're not just a face in the crowd

LONDON - The national surveillance network of vehicles is just the beginning of plans to monitor the movements of all British citizens.

The Home Office Scientific Development Branch in Hertfordshire is working on ways of automatically recognising human faces by computer.

Although the problems of facial recognition by computer are far more formidable than for car number plates, experts believe it is only a matter of time before machines can reliably pull a face out of a crowd of moving people.

If the police can show recording car movements can protect the public against criminals and terrorists, there will be a strong political will to do the same with street cameras designed to monitor the flow of human traffic.

Britain has a network of four million CCTV cameras - the largest in the world. On average, a Londoner is caught 300 times on CCTV a day.

The camera network, new ID software and a proposed national identity cards could eventually add up to a national database of faces.

The idea of such a database has already been floated, and liberty groups have said such a register will lead to surveillance of innocent people against their knowledge and an industry of private information sales.

A major feature of the national surveillance centre for car numbers is the ability to trawl through the records of previous sightings to build up an picture of a car's precise movements.

That could also be the case with a database of faces.

But police say camera use has been proven to help catch criminals.

A 13-month pilot scheme between 2003 and 2004 found that police access to automatic number plate recognition (ANPR) cameras led to a five-fold increase in the arrest rate. But mobile units will constitute a tiny proportion of the many thousands of ANPR cameras making up the network.

Hertfordshire's Chief Constable Frank Whiteley said the intention is to move from the "low thousands" of cameras to the "high thousands".

Just one camera can cover many motorway lanes. Two ANPR devices cover north and south movements on 27 lanes of the Dartford crossing toll area on the Thames.

By March, when the new system comes on line, most motorways, main roads, city centres and petrol stations will also be covered.

Some cameras may be disguised for covert operations but the majority will be converted CCTV traffic cameras.

More than 50 local authorities have already signed up to allow the police access to data gathered from their CCTV traffic cameras. The plan beyond March 2006 is to expand the capacity of the system to log the time, date and whereabouts of up to 100 million number plates a day.

"In crude terms we're interested in between 2 and 3 per cent of all vehicles on the roads," Whiteley said.

"The Road Traffic Act gives us the right to stop vehicles at any time for any purpose. So criminals on public roads are vulnerable.

"What makes them doubly vulnerable is that most criminals don't bother to tax or insure their vehicles."

Driving without vehicle insurance in Britain is against the law.

"We can concentrate our resources on the vehicles we should be stopping," Whitely said.

Asked whether ANPR will be as important to forensic work as fingerprints and DNA profiling, Whiteley said: "I would describe it as an ubiquitous policing tool. You can use it in all sorts of different ways."

- INDEPENDENT