The head of a Sydney-based halal certification body has launched legal action in the New South Wales Supreme Court against the anti-Muslim organisation, the Q Society.
Mohamed El Mouelhy from the Halal Certification Authority is suing the Q Society, its national president Debbie Robinson, and two other board members.
Also named in the statement of claim is known anti-Halal advocate Kirralie Smith, who holds membership of the Q Society.
The case centres on two videos posted online by the Q Society.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Mr El Mouelhy told SBS some of what's said in the videos is damaging to his reputation.
Respondents from the Q Society have declined to be interviewed by SBS.
(Click on the audio tab above to hear the full interview)

