The podcast that re-ignited public interest in the disappearance and suspected murder of Sydney woman Lynette Dawson may have "contaminated" evidence that would be used to prosecute her husband Chris for her murder, Mr Dawson's lawyer has warned.

Mr Dawson's solicitor Greg Walsh said on Thursday that The Teacher's Pet, a podcast by The Australian newspaper into the 1982 disappearance and suspected murder of the mother of two, may have jeopardised the case and posed a "very real" risk of contamination of evidence.

Chris Dawson (left) and brother Peter Dawson leave the Downing Centre court on Thursday. Credit:AAP

The podcast was released in May last year. Behind the scenes, detectives from the Homicide Squad’s Unsolved Homicide Unit had been reinvestigating the cold case since 2015.

Mr Dawson appeared briefly in Sydney's Downing Centre Local Court on Thursday. The former Newtown Jets rugby league player was charged in December with murdering his wife and is expected to enter a plea of not guilty.