So a speed camera is to be removed from the M4 because it has the side effect of causing congestion. Safe Speed applauds - finally - the acknowledgement that speed cameras come with negative side effects.

Paul Smith, founder of the Safe Speed road safety campaign(www.safespeed.org.uk) said: "The removal of the M4 camera represents the first substantial acknowledgement that speed cameras have side effects. There are many more real horrors to come."

"It is both a scandal and a tragedy that speed camera side effects have not been studied. The side effects are terrible and ensure that the cure is far worse than the disease. Safe Speed maintains a list of 30 different side effects resulting from speed cameras, many of which strike directly at the core of road safety."

"When all the side effects are finally acknowledged and evaluated, the full horror of the speed camera folly will be revealed. Speed cameras will go down in history alongside thalidomide as a truly dreadful mistake."

"The greatest cluster of side effects impinge directly on driver quality.Everyone knows that drivers are getting worse, and TRL says road deaths aren't falling as expected because of it. I know for sure that speed cameras are right at the heart of the problem. They have replaced genuine life-saving policies and distracted everyone from far more important safety factors."

"Road deaths are running 1,200 per year about projections based on earlier trends. I am certain that bad policy founded on speed cameras is responsible for this tragic and scandalous loss of life."

"Let's make speed cameras as unacceptable as drink driving."