New Zealand Prime Minister John Key said he ''took the message seriously'' and would put a series of proposals to cabinet next week, but added there was no intention to change the law. In most Australian states, a parent can lawfully smack a child when it is "reasonable chastisement". Politicians are loath to touch the emotive issue, which polarises debate between those claiming such laws sanction child abuse and those defending parents from "nanny state" interference. But pressure is building on governments to ban corporal punishment in the home. Separate bills in 2007 in South Australia and Queensland have sought to restrict parents' right to strike their children. In 2002, NSW went some way by outlawing force to the head or neck, or where it could harm a child "for more than a short period". Australian courts have gone further, banning parents from physically disciplining their children altogether. The Family Court last year restrained a mother from using physical punishment against her children aged 9, 10 and 12. In a 2007 case, where a father smacked his three-year-old son for refusing to pick up his toys, Justice Mark Le Poer Trench said: "There can be no defence of corporal punishment for young children in an advanced Western civilised society."

Similarly, in June, a 42-year-old Darwin father was reportedly fined $1000 for smacking his five-year-old daughter with a belt four times on the bottom. "In the modern age, physical punishment of children is seen to be barbaric," the magistrate said. The United Nations has twice criticised Australia for failing to prohibit corporal punishment in the home, in accordance with its obligations under the Convention on the Rights of the Child. More strident criticism is likely when the UN revisits the issue soon says James McDougall, director of the National Children's and Youth Law Centre. "A number of Latin-American and European countries have banned corporal punishment. There are signs Australia is moving in the same direction. Internationally, the expectation is that we will have a fresh look at it," he said. Such legislation has been enacted in 24 countries, a third of them in the past two years, according to advocacy group End All Corporal Punishment of Children. Bernadette Saunders, a senior research fellow at Child Abuse Prevention Research Australia, within Monash University, says children here are the only people against whom violence is sanctioned and justified as discipline.

Corporal punishment can have a detrimental impact on their behaviour, she says. Various studies have linked such force with increased child aggression and delinquency, and increased adult criminal and antisocial behaviour. "It's not appropriate to hit adults, so why is it for children? Children are vulnerable and parents have a huge responsibility to teach them positive ways of behaving," she said. School-aged children in Australia are twice as likely to be killed as their British peers, usually as a result of child abuse by their mother or her de facto partner, according to a study in the Medical Journal of Australia in January. The study's authors, from St Vincent's Hospital in Sydney, argued measures to reduce the rate of physical abuse of children, including banning corporal punishment, would have the greatest potential to reduce the number of children being killed. Fatal child abuse declined to "very low levels" after corporal punishment was banned in Sweden in 1979, they found. But Victoria's Child Safety Commissioner Bernie Geary says current laws already draw the line against child abuse. "I think anything that a parent does out of frustration or temper is absolutely wrong, but we should be able to decipher between what is child abuse and what is not," he said. "People who tap their children on the bum shouldn't be made to feel like criminals." Parenting methods are changing in any event, he said. "I was punished in a corporal way when I was a child and when I was a parent I whacked my kids, sometimes out of frustration. I never see parents now smacking their children … They're much more thoughtful about it," he said. A survey by the Australian Childhood Foundation found 69 per cent of adults in 2006 thought it sometimes necessary to "smack" a naughty child - down from 75 per cent in 2002.

But such minimal force is unlikely to be caught under an anti-smacking law such as New Zealand's, where parental force for the purpose of correcting a child is banned. The 2007 law won bipartisan support because of provisions permitting parents using reasonable force to prevent or minimise harm to the child, or to stop them engaging in offensive or disruptive behaviour. Police, the law states, have the discretion to dismiss complaints where the offence is "inconsequential". No prosecutions have been brought for smacking children under the new law, which has had "minimal impact" on police activity, New Zealand police say. Judy Cashmore, president of Defence for Children International, says parents should be educated on appropriate forms of discipline. "What people think is a smack can vary broadly. For some people it might be a slight tap on the hand; for others a belting would be seen as quite appropriate," she said. "The reason for having some change in the law is not to prosecute parents but to give them guidance as to what is appropriate.'' A spokeswoman for Community Services Minister Linda Burney said smacking was legal in NSW but the law contained provisions to safeguard children from ''serious physical harm''.

''For many parents, the commonsense approach works best,'' she said. ''In NSW the law says parents cannot use excessive physical punishment on any part of their child's head or neck, or any other other part of their body if the harm it causes lasts more than a short time. If parents feel they are not coping, they can contact Parentline on 1300 130 052.'' A spokesman for NSW Opposition Leader Barry O'Farrell said the Coalition supported current policy.