Dr Tim Soutphommasane will warn people against the proposed changes in a speech at the University of Canberra tonight.
The proposed changes to the Racial Discrimination Act started with Australia's most read columnist, Andrew Bolt.
Mr Bolt was pursued, in a civil case, under the act for what he wrote about ‘fair skinned Indigenous people milking the system.’
Dr Soutphommasane says while people have the right to free speech, they also have the right not to be vilified.
But Senator George Brandis is championing the changes, and Dr Soutphommasane says alterations could affect the rights of minority groups.
“The danger of repealing or significantly amending the law is that it may remove the legal avenue for people when they experience racial discrimination. It may well mean that they can only resort to law if there is a physical assault,” said Dr Soutphommasane.
Dr Soutphommasane says his warning message is just a part of his job.
“I have to call things as I see it and as I see it there is a very significant risk that we might be sending a green light to racists if you repeal or significantly amend the racial discrimination act,” said Dr Soutphommasane.
The changes are still under review but newly appointed Human Rights Commissioner, Tim Wilson wants a full repeal.
However, the Greens say the laws don't need to be changed.
“It was put there for a reason, we don't think it unduly impinges on free speech, of course we'll have a look at any legislation that the government wants to put up,” said Greens member for Melbourne, Adam Bandt.
This debate started last year when Tony Abbott and George Brandis promised changes during the election campaign.
Modifications were initially threatened during the Howard years but no changes were made.
The Attorney General says he's consulted with ethnic groups and any legislation will be well thought out.