The escape of armed robber Andrew Ivison illustrates what is wrong with our criminal justice system.

A judge sentenced him to six years in prison presumably because that is what his crime deserved.

But after a year in Bullingdon Prison, near Bicester, he was transferred to the super-soft Springhill Open Prison, near Aylesbury.

Surprise, surprise, he stayed there two weeks, then scarpered.

Now the police have to use their scarce resources to try to recapture him.

Ivison may not be one of our most dangerous criminals, but he is clearly prepared to use violence he threatened an assistant with an iron bar when he raided the Co-op shop in Kidlington.

Is there any guarantee that he won't use similar violence in future?

No doubt Ivison was transferred to an open prison not because he is a reformed character, but because our jails are bursting at the seams.

If we need more prisons, we should build them.

The public deserve protection from the likes of Ivison for rather longer than 12 months.