The young man in blue overalls and yellow bib shovelling clay with gusto from a hole in the road attracts little attention from passing drivers and pedestrians.

The government is paying close attention to the working lives, not just of 20-year-old Dean, but of scores of other men doing similar jobs with the gas mains. The result is a new approach to rehabilitating offenders that ministers believe will dramatically slash recidivism, which currently costs an estimated £11bn a year.