"Winston has carried on this tirade for a long time and I don't think that anything that I'm going to say is actually going to make a leopard change his spots, to be perfectly honest," Dame Susan told Q+A.
"I think there has been little response from some of those groups [targeted by Mr Peters] ... because I think they're just sick and tired of hearing Winston talk about that."
She said she had previously declined to speak on the topic because "I wasn't going to give him any oxygen".
"But I'm sure the occasion [to get involved] will arise leading up to the next election," she said.
Dame Susan said she had changed her views on cartoons printed in two South Island newspapers depicting Maori and Pacific Island stereotypes, which she had previously said were offensive but not racist.
"In my opinion, yes it was [racist]. But it doesn't meet the threshold and the limits of freedom of speech," Dame Susan said.
"What we're saying here is that the law is not the be all and end all of everything. We can't hide behind it and we can't always use it to its best effect but what we can do is exercise some civil responsibility.
"Sometimes we have to make personal choices, we have to look at our own behaviours and attitudes ... sometimes we have to look and say 'that is not right'."
