No evidence that 20mph zones improve road safety

THERE is no proof 20mph limits make roads safer, according to an official report that found half of all motorists ignore the restriction because they do not believe they will be caught.

A study commissioned by the Department for Transport found there was “insufficient evidence” to conclude there had been a “significant change” in the number of crashes and casualties following the introduction of go-slow zones in residential areas. Just 51 per cent of motorists were found to have complied with new 20mph limits – a statistic likely to raise major concerns among road safety campaigners.

Drivers said this was largely because of the lack of enforcement of the speed restriction, with the report blaming a “widespread view” that the chances of being caught were “very small”.

The report said the Department for Transport should update guidance to local authorities to encourage them to make 20mph limits more effective and to address the view the limits were not enforced.

It said where proactive enforcement by the police was not practical, councils should consider other methods to make motorists slow down, such as the use of vehicle activated signs.

The law was changed in 1999 to allow local authorities to designate 20mph speed limits without needing the prior approval of ministers.

Revised guidelines were published by the Department for Transport in 2013 which encouraged councils to consider introducing more 20mph limits. Motoring groups said the report showed careful consideration was needed as to where the limits should be rolled out.

Edmund King, the AA president, said: “Speed limits need to reflect the nature of the road so that drivers can easily understand why the limit is set.

“We believe that targeted 20mph limits work best on roads where there is an obvious need: outside schools, hospitals or where older and other vulnerable road users are likely to be encountered. Limits are more effective when accompanied by road engineering features. Blanket 20mph limits dilute effectiveness and compliance.”

The report said: “There is a widespread view amongst the public that 20mph limits are not enforced, and the likelihood of being caught exceeding the limit is very small.” The desire to improve road safety had been the main driver behind the introduction of 20mph limits. But the report said there was not enough evidence to conclude that they made people safer.