The Human Rights Commission says it is "dealing with" a cartoon published on Cameron Slater's Whaleoil blog.
"We are constrained in what we can say about the cartoon as we have received complaints and are considering our response in accordance with processes defined by the Human Rights Act," says chief mediator Pele Walker.
The cartoon, signed with the name BoomSlang, was uploaded to the site by 'Whaleoil Staff' on May 9.
"I would like to welcome a new cartoonist to Whaleoil," the post reads.
"I would like to, but I can't. This one was sent as a sample, and I've offered a regular slot. But BoomSlang is still ambivalent, prevaricating between just sending an occasional one and gracing our pages with regular contributions."
The cartoon shows a Maori child, bruised and cut, wearing a reusable nappy and clutching a similarly damaged teddy bear. The image is accompanied by the phrase: "Ta moko is the marking of the body by Maori... Can be added to over time if prior applications start to fade!"
Whaleoil readers seemed to like it, though one suggested "publishing this sort of stuff just gives the leftests ammunition to selectively use against this blog [sic]".
Slater says BoomSlang's next cartoon will go online on Monday.
Slater declined to comment when contacted. In a blog post earlier today he vowed never to talk to MediaWorks, which owns Newshub, "as long as I live".
The cartoon follows the tragic case of Moko Rangitoheriri, a three-year-old whose killers avoided murder convictions.
A New Zealand child aged 14 or younger dies as a result of neglect, abuse, or maltreatment on average every five weeks. Nearly half are Maori.
Former Children's Commissioner Dr Russell Wills says New Zealand's high levels of family violence and inequality are a major factor driving child abuse. His replacement, Andrew Becroft, will oversee big changes at Child, Youth and Family, which will be undergoing a significant overhaul in the next few years.
Earlier this week Slater was outed as being behind a failed plot to hack into a rival blog.
Newshub.
