A Sydney magistrate says broad and lengthy media scrutiny of the case against former PE teacher Chris Dawson is unprecedented and could prejudice his murder trial.

Key points: Chris Dawson has plead not guilty to the murder of his wife Lynette who disappeared in 1982

Chris Dawson has plead not guilty to the murder of his wife Lynette who disappeared in 1982 The case was featured in a podcast, The Teacher's Pet

The case was featured in a podcast, The Teacher's Pet The podcast is still available on social media despite its producers, The Australian newspaper, withdrawing it

The 71-year-old appeared in Sydney's Downing Centre Local Court today for the first time since he was issued with a new charge of carnal knowledge relating to his time as a teacher in the 1970s and 80s.

He has pleaded not guilty to murdering his wife Lynette, whose 1982 disappearance from Sydney's northern beaches was extensively covered in a crime podcast called The Teacher's Pet.

The court heard the podcast was still being circulated on social media, despite The Australian newspaper giving an undertaking to pull it from its own website.

Deputy Chief Magistrate Michael Allen said during his involvement in criminal law spanning 35 years, he had not seen a matter come before court having received such intense scrutiny.

"Someone would have to, I suspect, be living in a cave or be naive in the extreme to perhaps ignore the potential for unfairness to any accused person that received this level of scrutiny so broadly and for such a long period of time," he said.

Mr Allen expressed concern the community's confidence in the justice system could be undermined.

"The law is here to, in its way, make sure the guilty are punished and the innocent are set free," he said.

"It's also here to ensure that people, even guilty people … are assured of a fair, transparent trial [and] proper and due process."

Lynette Simms and Chris Dawson met high school function, both aged 16, and married in 1970. ( Supplied )

The podcast is still available on US-run sites such as YouTube and Facebook and, while police are working on ways to remove it, Mr Allen admitted there was very little he could do about its availability, unless the problem was elevated to the Supreme Court.

Mr Dawson's lawyer Greg Walsh said his client was entitled to the presumption of innocence.

"It's of considerable concern because it's so prejudicial to my client," he said.

"He's repeatedly referred to as a murderer."

The court heard the author of the podcast, journalist Hedley Thomas, had produced "thousands of pages" of material at the request of NSW Police.

Mr Walsh previously alleged Mr Thomas used a clairvoyant in the production of the podcast, but Mr Thomas's barrister, Dauid Sibtain, today rejected that claim.

"He's never met with or used a clairvoyant," he told the court.

Mr Sibtain said it was also incorrect to allege Mr Thomas was given access to police files.

The matter will return to court in September ahead of a five-day committal hearing in February, when several witnesses will give evidence.