A Sydney university student wrongly accused of terrorism offences is suing Mark Latham for defamation, claiming tweets by the One Nation candidate "gravely injured" his character and reputation.
Mohamed Kamer Nilar Nizamdeen was charged in August 2018 with creating a document in connection with preparing for a terrorist act, following the discovery of a notebook containing threats to kill senior politicians and blow up a number of sites.
He spent four weeks behind bars - including time in SuperMax - but was released after police admitted he probably didn't write the threats and dropped the charges.
Colleague Arsalan Khawaja was later accused of trying to frame Mr Nizamdeen.
Following Mr Nizamdeen's arrest, Mr Latham published a number of tweets assuming the University of NSW student's guilt.
As of Wednesday, the posts have not been deleted.
In a statement of claim lodged with the Federal Court in Sydney, Mr Nizamdeen's lawyer argues the tweets are defamatory.
"By reason of the publication and republication by (Mr Latham) ... the applicant has been brought into hatred, ridicule and contempt, and has been gravely injured in his character and reputation," the document states.
"(He) has suffered hurt and embarrassment and has suffered and will continue to suffer loss and damage."
Mr Nizamdeen says the damages he's entitled to have been aggravated by Mr Latham's failure to withdraw the comments, delete the posts, and apologise after the charges were dropped.
Mr Latham - who is running for a seat in the NSW upper house in Saturday's state election - said he has not been served with any legal papers.
"The last days of an election campaign always brings out the crazies - this stunt appears to be one of them," he said in a statement to AAP.
"I'm not going to be distracted from my election campaign."
Mr Nizamdeen's lawyer told AAP on Wednesday his client was also considering legal action against Senator Fraser Anning over similar material.
The controversial Queensland senator has been sent a concerns notice which is the prelude to potential litigation.
Australian Associated Press