A recent Supreme Court case has thrown a new light on the controversial issue of whether it's legal for a parent to smack their child in order to administer discipline.

It began with a father in South Australia delivering three slaps to his 12 year old son, twice on his shorts and once on his bare thigh that left a redness on the skin but no bruise.

The father shared custody with his estranged wife, the boy's mother, and he administered the disciplinary smack after the boy threw a tantrum at lunch and showed disrespect to his father and stepmother.

The mother reported the incident to police, and the father was convicted of assault in Adelaide Magistrates Court. He appealed to South Australia's Supreme Court where the conviction was overturned.

The judge said the original trial was misdirected on the issue of parental correction. Justice David Peek said the smack was "not unreasonable" for the purpose of correcting misbehavior.

The judge took into account the father had tried to instill self-discipline in his son by giving him 'time out' , but it didn' t change his behavior.

"The suffering of some temporary pain and discomfort by the child will not transform a parent attempting to correct a child into a person committing a criminal offence," Judge Peek said.

"Indeed, the very suffering of temporary emotion may be calculated to impress the child and correct the behaviour, just as much as the accompanying physical discomfort.

"Some level of pain is permissible, and in the present case there was little. The mere existence of red marks caused by the punishment does not prove unreasonable correction."

Solicitor Anneka Frayne from Stacks Law Firm said the Supreme Court decision was interesting in law, but stressed that while many other countries have instituted legal bans on corporal punishment of children including New Zealand, Germany, Italy, Hungary and Greece, there is no anti-smacking law in Australia.

However the way in which a smack is administered is covered by law. In NSW the laws of parental smacking are defined in Section 61AA (1) & (2) of the Crimes Act 1900.

"In NSW the defence of 'lawful correction' says parents can apply physical force to punish their child so long as it is 'reasonable' in the circumstances. Obviously what's reasonable is not always clear cut and can be open to different interpretation by courts," she said.

"The law gives some guidance though. It says it's never reasonable to apply force to a child's head or neck (except where the force applied is 'negligble' ) or to apply any force that causes harm for more than a short period. Obviously it's best not to smack your child but if you feel that it's necessary to change their behaviour, be mindful of the law and don't overstep the mark."

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