Race Relations Commissioner Joris de Bres has again criticised Hone Harawira for making racially offensive comments, saying in a report released today political parties should have codes of conduct that did not tolerate such behaviour.

The Maori Party MP's "white motherf**kers" comment in an email in November last year resulted in a the commissioner receiving a record 814 complaints.

Mr Harawira was defending an unauthorised trip to Paris while on a parliamentary visit to Europe, and he implied in the email that Pakeha critics were being hypocritical because white people had been "raping our lands and ripping us off for centuries".

Mr de Bres said the "white motherf**ckers" comment was "clearly very offensive" and had been compounded by the reference to "raping our lands".

"They were potentially divisive in the sense that they were negative about Pakeha," Mr de Bres said.

"Rather than provoke widespread hostility against Pakeha, however, they attracted criticism of the author and expressions of anti-Maori sentiment."

Mr de Bres criticised Mr Harawira at the time, and in his review report he said it was "highly inappropriate" for an MP to make such comments.

"While the words used would be offensive if used by a private citizen, they become more so when expressed by a person holding public office," he said.

Mr de Bres noted in the report that Mr Harawira had twice apologised and the Maori Party had deplored his actions.

"The New Zealand bill of Rights Act protects freedom of speech, and the limitations on it in the Human Rights Act relate to words that incite but not to words that offend," he said.

"While there is no legal sanction against racially offensive language specifically, this does not make it acceptable."

The review report sets out in detail the laws around freedom of speech and the sequence of events surrounding the controversy.

Mr de Bres said it had brought to light the need for further public discussion about how racially offensive language could be dealt with without unnecessarily fettering freedom of expression.

Mr Harawira's circumstances were unusual because MPs did not come under normal employment relationships - they were publicly elected and were accountable to their electorates, he said.

"Political parties should have policies and codes of conduct that do not tolerate racially offensive comments," he said.