Heavy lorries are causing Gatsos to record false readings, according to one report. The phenomenon has been admitted by the Lancashire Partnership for Road Safety, the speed camera operator, which has called it the shutter effect.
It's caused by the vibrations generated by juggernauts as they grind past. Accompanied by continuous heavy lorry traffic, one camera on the A59 near Preston reportedly flashed every car that went past, irrespective of speed.
The problem's not confined to the UK either. In Australia, where so many roads are long and empty, but the speed limits are low, New South Wales authorities have been forced to annul 26 inaccurate tickets dished out by speed cameras in similar circumstances. For instance, a bus with a maximum speed of 82mph was ticketed for a speed of 87mph. Eventually, the particular camera was removed - even though it was generating AUS$1 million annually in fines.
The Lancashire authority said, however, that it had issued no such inaccurate tickets.
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