Police, camera, obscura

They have names like Snooper and Road Angel and, according to the manufacturers, can tell you about police speed-traps long before you arrive at them. This type of radar detector has seemingly become a dashboard necessity in the motorist's battle to keep one step ahead of the road-side technology deployed by the police. But now the Government has decided to follow the lead of other European countries and outlaw the use of some devices. So it's important to know just what you can and cannot use.

The Road Safety Bill, expected to become law in April, will ban gadgets that can detect whether a police camera or speed gun is in use. Crucially, though, the legislation won't stop drivers using devices using GPS technology or other databasestthat identify the position of a speed trap or a mobile police camera unit

This information is already available through a number of organisations. For the law-abiding motorist this means that he or she will still be able to fit a device to a vehicle that will tell where a camera is located, but won't be able to operate technology that tells them which ones are non-functioning.

Andrew Howard, the head of road safety at the AA Motoring Trust, says this is a sensible compromise that will stop drivers speeding with impunity in areas that are policed by the ubiquitous yellow boxes. He says: "We have always been concerned about radar detectors because it means someone can drive around a housing estate at 30 mph when they know the cameras are working and then race off at 50 mph when they discover they are switched off."

This is a view shared by the Parliamentary Advisory Council for Transport Safety. Its executive director, Robert Gifford, says: "Competent drivers should not need a camera detector. They should be thinking all the time about the driving task, not allowing themselves to be distracted by technology that is of limited benefit and soon to become illegal."

But the proposed ban on radar detectors is not good news for the thousands of motorists who have each paid hundreds of pounds for the state-of-the-art equipment. The Government has no plans to compensate them for the estimated millions of pounds that they will have spent. Even so, the legislation won't come into force until 2006, and so recent purchasers will still get at least a year's worth of use out of their detectors.

There are also scientific advances that may soon make radar detection technology obsolete. A new police device being tested in America doesn't emit any energy and therefore is "invisible" to the conventional detectors. The video camera inside the box is linked to a computer that compares the speed of a car to a motionless target - such as a tree by the side of the road.

Expect these new devices to be appearing in a yellow box on a British roadside very near you very soon.