Brake chief executive Mary Williams called in police after being singled out by anti-camera campaigners. The road safety charity confirmed its founder had been the subject of alleged death threats that appeared on a website for sports car enthusiasts.
It was reported that one member suggested she be 'knocked off' or have her brake cables cut and another described her as a witch who should be burnt at the stake.
The Association of British Drivers (ABD), which is against speed cameras, has called for the speed camera issue to be debated calmly, claiming it had always used reasonable and rational arguments to promote its 'well thought out views on road safety'.
It added: 'The ABD believes that the so-called death threats against Mary Williams came from individuals, not organisations. We are disappointed to see the Parliamentary Advisory Council for Transport Safety (PACTS), of which the ABD is a member, joining in an effort to tar opposing viewpoints with this brush.'
Meanwhile PACTS has issued a document entitled 'Ten Criticisms and Why They Are Flawed'.
The research briefing claims to review the research evidence related to 10 arguments put forward by critics of speed cameras which include: Cameras cost lives, speed is not a major factor in road casualties, raising speed limits in the USA made no difference to casualties, cameras are not popular and cameras have contributed to a fall in traffic policing.
Opposing organisation Safe Speed claims to have spent more than 4,000 man-hours investigating the overall effects of speed cameras on UK road safety.
It says that the fatal accident rate, which it describes as the most important road safety indicator, is showing its poorest performance in modern history.
A spokesman said: 'Fatal road accidents are now higher than they were in 1998 – and this despite lower traffic growth than previously. It all began to go wrong when speed cameras were introduced.'