found this on the abd.org.uk baiscly uks version of usa's ''motorists''

New research from road safety group the Association of British Drivers today damned the M4 speed cameras as "a massive mistake".
The Association was also charged 111 for access to vital information about the causes of crashes which, it believes, should have been made public.

In data provided by Wiltshire Constabulary, driver inattention topped the list of accident causes, followed by poor lane changing and careless/reckless behaviour. In fact, not one single accident had excess speed as the sole cause.

But included in the crashes that allowed the Partnership to use speed cameras were:
an accident where a pedestrian fell from a bridge
an accident where a gust of wind pushed one lorry into another
several tyre blowout accidents
a crash where a car drove the wrong way up the motorway
"Excess speed" came fifth on a list of accident causes along with driver fatigue a factor likely to be made worse by the stress caused by the presence of speed camera vans. "Excess speed" includes accidents where vehicles were travelling within the speed limit but too fast for the conditions — e.g. in fog — where cameras could have no effect.

Mark McArthur-Christie, the ABD`s Road Safety Spokesman, said:
“ These statistics show clearly that speed is far from the most significant factor in crashes — but no matter what the causes, the Partnership still thinks cameras are the solution. These figures show that cameras on the M4 will do absolutely nothing for road safety. They should be withdrawn immediately.”
In investigating the causes of M4 crashes, the ABD found that hard data was next to impossible to acquire. The camera Partnership even initially denied that they held data on the causes of crashes. After requesting information from a range of departments and organisations, a request under the Freedom of Information Act was also turned down. The ABD was finally forced to pay 111 to Wiltshire Constabulary for the data.

McArthur-Christie continued:
“ This data — now we`ve forced it into the public domain — raises very serious questions about the use of speed cameras on the M4. It also raises questions about why the data has not been made public before.”
Brian Gregory, the ABD`s Chairman, said:
“ This work shows clearly that we need to get away from the whole "The answer`s a speed camera, now what`s the question?" approach to road safety. We also want to see Partnerships forced to publish the causes of crashes they use to justify cameras.”


Notes for editors

The major causes of M4 crashes, 1999-2004 were:

Inattention — a factor in 28% of crashes
Failure to judge others path or speed (ie poor lane changing) — a factor in 28% of crashes
Lack of judgement of own path a factor in 17% of crashes
Fatigue — a factor in 14% of crashes
Careless, thoughtless or reckless behaviour — a factor in 14% of crashes
Excess speed — a factor in 14% of crashes
"Excess speed" is speed which is too fast for the conditions as well as speed in excess of the posted limit. As such, it is impossible to find out how many crashes were caused by drivers exceeding the limit and how many by simply too fast for the conditions.

Significantly, the causes of crashes are given rankings by accident investigators. They class causes as definite, probable and possible. Excess speed was ranked as a definite cause in just one fatal crash — less than 1% of all accidents.

*Data from Wiltshire Constabulary, M4 crashes 1999-2004


they use whatever excuse they want