SPEEDING drivers on the A34 escaped without penalty because dummy speed cameras did not contain any film.

The empty cameras have watched over drivers between the Pear Tree interchange in Oxford and Weston-on-the-Green on the A34 since September while workmen resurfaced the road.

But not a single driver was caught breaking the reduced 40mph limit because none of the temporary roadside boxes contained film. Similar temporary speed cameras were also installed during roadworks on Oxford's Northern Bypass.

Dan Campsall, spokesman for the Thames Valley Safer Roads Partnership, said: "We believe that the presence of the cameras did have an impact on vehicle speeds.

"The Safer Roads Partnership and Highways Agency would like to thank drivers for their patience and co-operation through the period of the roadworks. In the event that future roadworks present similar issues, it is likely that mobile enforcement will be introduced to supplement the presence of fixed cameras."

Six speed cameras were put up on the northbound and the southbound carriageways of the A34 when work began in September.

They were finally taken down when the road was reopened last Thursday ahead of the Easter Bank Holiday.

Signs warned drivers of the reduced limit from 70mph to 40mph and the threat of speed cameras. More lane closures are due next week.

Money for the cameras came from the contractors carrying out the roadworks and did not cost the taxpayer a penny, spokesman Mr Campsall added.

Empty cameras situated on Oxford's Northern Bypass during roadworks between Green Road Roundabout and Cutteslowe Roadabout in December also led to no fines or penalty points being issued.

During 2005, Thames Valley Safer Roads Partnership cameras caught 54,612 motorists, making about £3m fines, despite only ten per cent of them loaded with film.

"We are not interested in raking in lots of money. Our priorities are reducing casualties," Mr Campsall said.

A spokesman for the Association of British Drivers said: "Vehicle-activated signs would have been far more appropriate for this stretch of road and the fact that the cameras are dummies will probably undermine public belief in speed cameras."