Smacking children 'causes long-term damage' Smacking and other violent forms of discipline are likely to be harmful to the long-term development of children, a study into the effects of physical punishment has claimed. Campaigners said the findings, based on a comprehensive analysis of two decades of research, showed it was time for the Government to yield to international pressure and finally ban smacking in Britain. As well as making children more aggressive towards parents and siblings - and later in life towards their peers and spouses - the Canadian study found that physical sanctions can lead to increased levels of antisocial behaviour. Smacking can also cause depression, anxiety and drugs and alcohol abuse, the study claimed. The findings come after the former Labour Education minister David Lammy reignited the debate over the issue when he claimed that many working-class parents were confused over the laws governing smacking. Mr Lammy admitted he had smacked his children and suggested that curbs on traditional discipline might have contributed towards the social breakdown witnessed during last summer's riots. London Mayor Boris Johnson also called for clarification of the law to reassert parents' rights, claiming he was backed by the Education Secretary Michael Gove. But in an article published in today's Canadian Medical Association Journal, two leading childcare experts have argued that 20 years of evidence shows such an approach is counter productive. "Virtually without exception, these studies found that physical punishment was associated with higher levels of aggression against parents, siblings, peers and spouses," said Dr Joan Durrant, of the University of Manitoba, and Ron Ensom, of the Children's Hospital of Eastern Ontario. Results consistently suggest that physical punishment has a direct causal effect on externalising behaviour, whether through a reflexive response to pain, modelling or coercive family processes. The authors said a trial involving more than 500 families trained to use non-physical punishments found that problem behaviour declined.