A defamation case between a halal certifier and an anti-halal campaigner in the New South Wales Supreme Court is being closely watched by some of the country's highest profile conservative politicians.

Key points: Kirralie Smith believes money collected through halal certification could be directed into promoting terrorism

Kirralie Smith believes money collected through halal certification could be directed into promoting terrorism Halal Certification Authority president is suing Ms Smith for defamation over online videos

Halal Certification Authority president is suing Ms Smith for defamation over online videos Coalition MP George Christensen will speak at a fundraiser to pay for Ms Smith's court costs

On one side is Kirralie Smith, a leading figure in anti-Islam party Australian Liberty Alliance, and founder of the Halal Choices website.

"My primary concern, and why I started Halal Choices seven years ago, was because most halal certified foods are not clearly labelled, so the consumer is paying the fees without their consent," she told 7.30.

She is concerned that money collected through the certification of halal food could be directed into organisations which promote terrorism.

On the other side is Mohamed El-Mouelhy, president of the Halal Certification Authority.

"Halal certification is an industry and it is bringing in a few billion dollars. Last year I think it was about $13 billion. It is a requirement by all Muslim countries," he told 7.30.

He said that what he did with his money was of no concern to anyone else.

"What I do with my money is my business," Mr El-Mouelhy said.

"Everybody supports their own faith, so why is supporting my own faith wrong but supporting other faiths is right?"

'I have every right to sue'

Mr El-Mouelhy is suing Ms Smith for defamation over a number of online videos she presented for the Q Society, another anti-Islam group affiliated with the Australian Liberty Alliance.

"When you make false exaggerations I have every right to sue and sue everybody that has supported her and paid for her video," he said.

But for Ms Smith and her supporters it is a matter of free speech, and she is now counter-suing Mr El-Mouelhy.

"There have been ongoing social media posts that are defamatory to us, and we see that is the best way to bring these issues to the public," she said.

"He says he can back up his claims that I'm a racist and a bigot, and we'll see whether he can.

"But I'm pretty confident I'm not a racist or a bigot. I'm simply criticising an ideology, I'm not criticising a people, group or an individual."

Defamation lawyer Jeremy Zimet said the online space was quickly emerging as a new frontier for defamation cases.

"It's important for observers to realise that there are consequences for posting publications online, whether it's on social media or review sites," he said.

George Christensen will speak at a fundraiser to pay for Kirralie Smith's court costs. ( Supplied: Facebook )

Ms Smith's opinions and political aspirations have caught the eye of conservative figures within Australian politics, including Coalition MP George Christensen, who will speak at a fundraiser to pay for Ms Smith's court costs.

"I'm backing Kirralie Smith because she is raising legitimate concerns that many members of the public share around halal certification, what the money behind halal certification actually goes to," Mr Christensen said.

"If she is ever inclined to join the LNP and the National Party then maybe there is a future for Kirralie in Canberra."

The court case begins this month.