Australian doctors have called for the smacking of children by parents to be made illegal, saying it was too easy to blur the line between reasonable discipline and abuse.
The Royal Australasian College of Physicians said Australian laws needed to be changed to make all forms of corporal punishment illegal "so the law protects children from assault to the same extent that it does all people".
"Many cases of physical abuse are the result of physical punishment that became more severe than intended," said Susan Moloney, president of the college's child health division.
"And the difficulty with allowing the physical punishment of children is that the line can easily be blurred between abuse and 'reasonable' force or chastisement that is currently permitted in some states when disciplining a child."
Research suggests most Australian parents smack their children, but acceptance of the practice is falling, with 75 per cent of adults surveyed in 2002 saying it was sometimes necessary to smack a naughty child compared with 69 per cent in 2006.
Moloney said studies were increasingly showing those subjected to physical punishment when young were at greater risk of harmful effects.
"These include mental health problems such as depression, anxiety, aggressive or anti-social behaviour, substance use problems and abuse of their own children or spouse," she said.
"While many children will not experience negative outcomes as a result of moderate or reasonable physical punishment, why put your child's future health and emotional wellbeing at risk?"
Moloney said the reform made sense given other laws.
"If you hit your dog you could be arrested ? but it's legal to hit your child," she added in an interview with the Sydney Morning Herald newspaper.
The college, which represents more than 14 000 physicians in Australia and New Zealand, said the physical punishment of children was already illegal in 33 countries, and there was evidence that the legal change and public discussion on the issue had helped shift attitudes.
It said these countries had also experienced other benefits such as increased early identification of children at risk of abuse and low rates of mortality associated with child abuse.
New Zealand introduced a law in 2007 which banned parents from smacking their children, meaning adults could no longer use "reasonable force" in disciplining their kids.
Other countries with a ban in place include Germany, Israel and Kenya.
The government said at the time it would help tackle New Zealand's poor record on violence against children after a 2003 UNICEF report found it had the third-worst rate of abuse and neglect among developed nations.