The repealing of section 59 of the Crimes Act meant New Zealand law had gone further than other Anglo countries, Associate Prof Joan Durrant, a children's clinical psychologist from the University of Manitoba, Canada, said.
"New Zealand should be very proud. This country had the courage to protect children and it was a very courageous move."
Speaking at the Children's Issues Centre national seminar in Dunedin on Saturday, Prof Durrant said other British countries had focused on the protection of adults rather than the protection of children as New Zealand had done.
"New Zealand's law is unique among those of the Anglo countries because it does not attempt to define `reasonable' corporal punishment, but prohibits all of it.
"We have just not made the message clear," she said.
In her country, Canada, "reasonable" could be defined as "transitory and trifling" force; in Texas "reasonable" ranged from the use of "non-deadly force".
These laws ended up failing to provide children with full protection and still condoned some level of violence towards them, she said.
"New Zealand is the benchmark other countries should be aiming for."
The repeal of section 59 of the Crimes Act would result in fewer New Zealand children being smacked and would go some way towards removing violence from society, she said.
"This can only be a good thing, but more education is needed to educate people about the law and also to promote positive information about child development."
As a parent, Prof Durrant said she could relate to the frustration parents felt when they were in a supermarket and their toddler misbehaved.
"This has happened to me. People look at you and think 'she is a bad parent' or 'that kid needs a good smack'. But what they don't know is that my child was sick and I took him to the supermarket before he got over his sickness. All I had to do was to take him home.
"I believe that every time we smack a child, we have lost an opportunity to show them there is another way."
