There is no doubt there is growing support for 20mph zones.

Many people are becoming fed up with drivers having it all their own way - racing along the streets in cars and lorries, as if no-one else on the road or pavement matters.

Oxford could become the first city in the UK to introduce a blanket 20mph speed limit, at cost of £300,000.

Portsmouth has led the way by slowly turning itself into a 20mph city. But Oxford could go the whole hog, by taking the "big bang" approach and introducing it overnight.

Depending on the outcome of the public consultation exercise, the new limit could be in force by the end of the year or next spring.

There is certainly merit in having a blanket limit, where motorists are in doubt of the maximum speed at which they should be travelling.

One of the criticisms of present speed limit policy is that confusion is caused because they change so frequently, often several times in the space of a few miles.

The danger is that drivers spend more time concentrating on signs than watching what is happening ahead of them on the road.

Speed limits aren't the panacea which will prevent all road deaths and injuries.

But there is no doubt that the slower a vehicle is going, the less severely hurt a casualty is likely to be.

The big question, of course, is - who is going to enforce the 20mph limit?

The police say it is not their policy to do so and there is some doubt whether roadside cameras can legally be used to apply the 20mph limit.

It appears that it will up to drivers to do the decent thing.

Will they do so? Some will, but judging by the number of speeding drivers on our roads at present, we bet there will be plenty who don't.

With 20mph zones becoming more widespread, it is time the police reconsidered their view.