Robert Farquharson's car plunged into a dam at Winchelsea in southern Victoria on Father's Day 2005.
He swam free, but his sons Jai, 10, Tyler, seven and two-year-old Bailey drowned.
The car was removed from the water the night of the crash. (HANDOUT/VICTORIA POLICE)
Farquharson had separated from the boys' mother and was returning home from an access visit at the time of their deaths.
He was found guilty of their murder in 2007, but his conviction was quashed on appeal in December 2009.
He was again found guilty in 2010 and sentenced to life with a minimum of 33 years, with a further two appeals later rejected.
Farquharson will base his latest appeal bid, scheduled for later this year, on Victorian laws introduced in 2019 that relate to new evidence that there has been a miscarriage of justice, his lawyer Luke McMahon confirmed to AAP.
Robert Farquharson (left) and Cindy Gambino at the funeral for their three children. (Julian Smith/AAP PHOTOS)
Mr McMahon said he intended to file the appeal in the coming months and had evidence he believed would satisfy the standard.
Farquharson's lawyers were considering research showing how cars sank in deep water.
Mr McMahon said his client stood by his story of what led to the children's deaths.
Farquharson has always maintained his innocence and two doctors diagnosed him with cough syncope, a condition that causes a person to pass out after a coughing fit.
That was contested by the prosecution and another medical expert who gave evidence in court.
The children died in a dam at Winchelsea in 2005. (Geelong Advertiser/AAP PHOTOS)
The 2019 laws were introduced to allow for appeals in substantial miscarriages of justice by introducing a second or subsequent right of appeal of convictions for indictable offences, in limited circumstances.
The changes were prompted by the the misuse by Victoria Police of gangland lawyer-turned-informant Nicola Gobbo and the case of accused police murderer Jason Roberts.
Roberts was the first to use the laws and in a 2022 retrial was found not guilty of the 1998 killings of Victoria Police officers Sergeant Gary Silk and Senior Constable Rodney Miller.
The mother of the three boys, Cindy Gambino-Moules, died in May 2022 after a medical episode at her home.
In January, Department of Health secretary Euan Wallace stripped Farquharson of rights over his children's graves.
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