Chin Tan, who took on the role three weeks ago, copped a barrage of questions about the white supremacist slogan during a Senate estimates hearing on Tuesday.

Mr Tan confirmed he was not asked for advice before government senators voted in favour of a One Nation motion endorsing the phrase last week.

The government later claimed its senators made a mistake, demanding a second vote to reverse its position.

Mr Tan, who released a statement condemning the inflammatory motion, was reluctant to express a personal view at the public hearing in Canberra.

But under persistent questioning from opposition and crossbench senators, the commissioner acquiesced.

"Racism in any form against anyone is unacceptable," Mr Tan told the committee.

Asked about the rise of the far right, Mr Tan said any increase in extremism or supremacy was concerning.

Liberal senator Linda Reynolds, representing the attorney-general at the hearing, was also grilled about why she initially voted for the motion.

Labor's Murray Watt also pressed Senator Reynolds about whether she understood the significance of the white supremacist phrase before casting her vote.

Senator Reynolds objected to the questions, arguing they were not relevant.

"This is not a forum for asking me questions on political issues," she told Senator Watt.

"Any grandstanding stunts are best suited for another place."

Senator Reynolds cited an earlier statement from the attorney-general, which blamed staffers for the "administrative error" and said the racist origins of the motion were not appreciated.

When Greens Senator Mehreen Faruqi pursued a similar line of questioning, Senator Reynolds claimed the pair were implicitly making the "deeply offensive" suggestion she was racist.

"The clear implication from your line of questioning is deeply political, it is deeply personal," Senator Reynolds said.

"For either of you to suggest - to use this politically to suggest - that I or any of my colleagues are racist is beyond offensive."

Mr Tan, whose predecessor Tim Soutphommasane was heavily criticised by the government for being too "divisive" and focused on negative trends, said he received no directions about how to conduct himself.

Australian Associated Press