Harry Fletcher, from the National Association of Probation Officers, said the idea of mentors was "excellent" but he thought it would never happen because of the sheer numbers needed to make it work. He told the BBC:
You'd need an army of volunteers or employees of private companies to do it properly.
More top news
Hundreds of facial hair aficionados from around the globe have taken part in the World Beard and Moustache Championships in Austria.
An airliner carrying 147 passengers had to make an emergency landing after the pilot died during the flight.
Health Secretary Jeremy Hunt has been urged to apologise for suggesting tax credit cuts will make Britons work harder.