Despite it’s oh-so clever name, the new generations of SPECS cameras can’t actually see very well.

Designed to calculate a vehicle’s average speed over a long distance, the "hi-tech" cameras can apparently be fooled by the incredibly fiendish tactic of a driver changing lanes. The Home Office admitted the failing, saying that provisions for the use of speed camera evidence made it clear that prosecutions were only valid if drivers are filmed in the same lane at both the start and finish of the recording.

SPECS is supposed to catch motorists that "camera surf", slowing down just before a fixed GATSO camera before speeding up again. If SPECS records a motorist’s average speed at above the specified limit, the penalty is set at £60 and three penalty points.

The fear now is that drivers aware of the loophole may increase the risk of accidents by continually switching lanes. Police have urged drivers not to exploit the shortcoming by trying to evade the cameras, while the company that manufacturers the cameras says drivers who skip lanes may still be liable for prosecution.

Sets of the cameras have been installed at 27 sites around the UK at a cost of between £180,000 and £1.5mn per site. Fourteen are permanent while another 13 are located at road works.

Last year, more than 2 million motorists were caught speeding on camera, raising £120 million in revenue.