Louis Theroux shares his advice on covering white supremacists with The Project NZ

Louis Theroux gave some advice on covering white supremacists in the wake of the Christchurch terror attacks during an interview with The Project NZ on Thursday night.

Ahead of his live stage show, due to arrive in Auckland early next year, the celebrity documentary maker gave some insight on his investigations into fringe subcultures in society.

Host Kanoa Lloyd made reference to Theroux's many interactions with racist groups, noting that New Zealand was currently grappling with how to report on the trial of the alleged Christchurch mosque gunman.

"As you probably know, Louis, we are really thinking hard at the moment in the media about how we cover white supremacists, whether we give them air time," host Kanoa Lloyd asked.

"I wonder if you can give us some advice on how to handle that, given your own experience?"

"That's a great question," Theroux responded.

"I used to take a maybe slightly naive view. You hear this term: 'Oh, I'm a free speech absolutist - this idea that there's no form of discourse that should be in any way constrained."

"I don't know that I've got a blanket answer for you, except that it is a real responsibility.

"When I've covered white supremacists, neo-Nazis, it's always been in the context of them being very, very fringe.

"It's the people who don't have access to power, and for whom their poisonous beliefs speaks to a lack of power that I feel that I'm then able to contextualize and kind of undermine."

The My Scientology Movie creator added that it was important not to give any extremists an "uncritical hearing".

Theroux said he was excited to come to New Zealand in 2020 - being a big fan of The Lord of the Rings - before querying: "Was that a patronizing thing to say?"

During his visit to Aoteaora, Jeremy Corbett suggested Theroux might like to look into some of the countries' infamous groups such as Destiny Church and Gloriavale.

"I wish I was taking notes," Theroux replied.

"Off air you'll have to tell me those again, and I'll make sure to do some research when I'm down there."

Louis Theroux: Without Limits will play at Auckland's Civic Theatre on January 10, 2020.