Child cruelty cases provoke strong reactions. But it is now accepted that while protecting the child is paramount, understanding the parent is better than punishment. John Robinson went to prison for attacking his 18-month-old son. Since his release he's been taken to court because, it was believed, he had again attacked the child, now aged 5. Robinson denied the charge and believes he is being victimised, blamed for every cut and bruise his child suffers. Harold Williamson follows the court case and also sees how some London mothers, who live in fear of repeating attacks on their own children, are being helped in an experiment run by the NSPCC.