The purpose of pavements is to provide a safe place for pedestrians to walk free of traffic.

Would legislation to enforce this universally acknowledged principle amount to a classic case of applying a sledgehammer to crack a nut?

The gradual takeover of pavements and footpaths by parked vehicles has become such a serious problem that Sandra White, MSP for Glasgow Kelvin, is preparing to introduce a Private Members' Bill in the Scottish Parliament that would make it illegal to park on the pavement or obstruct a dropped kerb unless there was a specific exemption.

The proposal is the result of a campaign by 21 bodies representing disabled people. They point out that even cars only partially parked on the pavement can form such an obstruction that pedestrians are forced out on to the road. While this is a minor irritation for the able-bodied, it can be very dangerous for the disabled. Those most at risk include wheelchair users, blind people and those with learning difficulties, all of whom are particularly vulnerable if they have to share the road with traffic. Most people will experience similar difficulties at some point in their lives. This could be as a parent wheeling a pushchair or taking small children by the hand. Equally, it could be as an elderly person unable to nip spryly out of the way.

The proposal to ban parking on pavements has already attracted sufficient cross-party support to be put forward as a Bill. However, there are serious concerns about the impact of such a measure. One is practicality. The problem is most acute in residential areas where houses and flats date from a time when there were few cars and there are not enough on-road parking spaces to accommodate residents' vehicles. The result can be a compromise by drivers who park with two wheels on the pavement to leave room and also allow traffic to pass on the road. In such situations a blanket ban would risk solving one problem by creating another in nearby streets; either that or impeding traffic.

Ms White has recognised that there would have to be exemptions. The process involved in obtaining orders and the additional responsibility of enforcing the ban would cause significant extra costs for local authorities at a time of budget cuts.

It is possible the prospect of a ban will inspire councils or community groups in some congested areas to find a way of creating more parking areas to keep pavements free of parked vehicles. Ms White, who is the third MSP to take on responsibility for introducing a ban, has already raised awareness of the problem.

This is a difficult area but drivers should let wheelchairs, buggies and guide dogs rule the pavements. If they did, there would probably be no need for legislation.