The 1988 Road Traffic Act, Section 39, puts a "statutory duty" on the local authority to undertake studies into road traffic collisions, and to take steps both to reduce and prevent them.
The pertinent wording from the Act is:
39.2 Each local authority must prepare and carry out a programme of measures designed to promote road safety and may make contributions towards the cost of measures for promoting road safety taken by other authorities or bodies.
39.3 Each local authority -
- Must carry out studies into accidents arising out of the use of vehicles on roads or parts of roads, other than trunk roads, within their area
- Must, in the light of those studies, take such measures as appear to the authority to be appropriate to prevent such accidents, including the dissemination of information and advice relating to the use of roads, the giving of practical training to road users or any class or description of road users, the construction, improvement, maintenance or repair of roads for which they are the highway authority and other measures taken in the exercise of their powers for controlling, protecting or assisting the movement of traffic on roads
So, without evaluation, how do local authorities know what measures are appropriate?