Mr Turnbull on Monday called on the commission to urgently review the way it manages race hate cases after "bringing" a case against three students that was last week thrown out by a Federal Circuit Court judge for having no reasonable prospect of success.

"What the judge was saying to the Human Rights Commission is, 'you've been wasting the court's time. You've been wasting government money'," Mr Turnbull told ABC radio.

He urged the organisation to reflect on whether it was acting in a way that was undermining public support for the commission and its promotion of human rights.

But Professor Triggs said the commission had no power to instigate court proceedings and revealed she had been urging the government to introduce a higher threshold before the commission was obliged to investigate hate speech complaints.

"The Prime Minister was deeply misleading in suggesting that we had brought the case. We never bring cases and we are purely passive in that sense. We don't prosecute, we don't pursue, we don't instigate proceedings," she told Fairfax Media.

"The judge did not make any comment on the Human Rights Commission and made no such extreme, provocative statement."

The government is poised to announce a parliamentary inquiry into the operation of section 18C of the Racial Discrimination Act, which makes it unlawful to "offend, insult, humiliate or intimidate" someone because of their race or ethnicity.

Critics say the law places an excessive curb on free speech and argue the Federal Circuit Court's decision in the QUT case and the commission's handling of a complaint against News Corp cartoonist Bill Leak demonstrates the need for reform. The Leak matter is unresolved.

But Professor Triggs argued the campaign is being orchestrated by News Corp and politicians "who have deliberately misunderstood the law".

"There is no doubt that they have deliberately undermined a process that proceeds quietly, with 20,000 matters, plus formals complaints, each year," she said.

She predicted a massive backlash from those who opposed changing the law during Tony Abbott's prime ministership.

"There will be a huge political response by the Jewish Board of Deputies, the Chinese community, the Vietnamese, the Muslim community. There are many, many groups who spoke up last time. Why you would expect that to have changed, I'm not sure."

The executive director of the Australia/Israel and Jewish Affairs Council, Dr Colin Rubenstein, has mounted a strong defence of 18C after the court decision, while accepting the conciliation process may "require further consideration and review".

"Especially at a time when xenophobia in Australia is rising, this legal provision continues to be essential in helping to maintain social cohesion while providing victims of racism with a just method for seeking redress where they have been the target of racial vilification," Dr Rubenstein said.

Professor Triggs said while the Federal Circuit Court had adopted a high threshold in ruling on breaches of section 18C, the commission was required by law to investigate and attempt to conciliate all written complaints. It did this in 74 per cent of formal complaints, with only one or two per cent going to court.

"Our statute requires us to accept the matter, as distinct from the Federal Court, which has got a much higher threshold," she said.

"Even if I know it would fail at the Federal Court, we are bound to accept the complaint in the hope of conciliating it. It's a form of social justice. It costs the complainant nothing and it costs the respondent nothing, unless they choose to go to lawyers."

Professor Triggs said the commission had urged the government for some years to change the legislation and introduce a higher threshold before the commission investigated complaints, without success.

She welcomed the prospect of an inquiry, saying the commission would make a submission supporting "a stronger 18C that gets the message out even more effectively that abuse on the grounds of race in the public arena is unacceptable".

Professor Triggs also defended the commission's handling of the QUT case, saying the complaint met the threshold when it was lodged. "We kept on with it because we had every belief in the university and the students and Ms (Cindy) Prior (the complainant) that they were acting in good faith and would conciliate.

"After twelve or thirteen months it became very clear that we could not conciliate and therefore we terminated it, which allowed the parties to go to court if they wanted to."