Leeds University has concluded the first phase in its test of "Intelligent Speed Adaptation," a technology that allows the government to take control of an automobile to ensure that it does not exceed the speed limit. The university is now equipping twenty Skoda Fabias with the £1300 (US $2300) GPS-enabled black box for series of six-month trial runs sponsored by the UK Department for Transport.

The device uses satellite positioning to determine the speed limit from a pre-programmed map of every road in the UK. The black box is able to take control of the car's accelerator and brakes to ensure that if a driver doing 20 MPH in a 20 zone tries to accelerate, the car simply will not respond.

London Mayor Ken Livingston wants to deploy the technology in his city. He proposes that anyone accepting the device would be offered a discount on the £8 (US $14) "congestion charge" assessed to motorists entering London.

Jeremy Clarkson, co- presenter of the BBC's Top Gear programme and a Sunday Times writer, disagreed. "If you put speed limiters on cars so that they can only go to a certain limit you end up with terrible bunching which actually causes more accidents," he said. "Tony Blair is not going to tell me how fast to go."