Susan Neill-Fraser and Bob Chappell (AAP Image/Sarah Bowles and Emma Fraser Meeke)
Hobart grandmother Susan Neill-Fraser is appealing to Australia's highest court for a second time in a bid to have her murder conviction overturned.
The 67-year-old was sentenced to 23 years in jail for killing partner Bob Chappell aboard the couple's yacht, the Four Winds, on Australia Day 2009.
Her appeal before Tasmania's Court of Criminal Appeal was dismissed in November, with two of the three judges finding new evidence did not meet the required threshold of "fresh and compelling".
Lawyers representing Neill-Fraser have lodged an application with the High Court seeking special leave to appeal the judgment.
Neill-Fraser's appeal was centred around the whereabouts of then-homeless teenager Meaghan Vass, whose DNA was found aboard the yacht.
It was put by the prosecution at the 2010 trial that the DNA deposit was a "red herring" and arrived on the boat via secondary transfer.
Ms Vass has given conflicting accounts about whether she was on the boat the night Mr Chappell was murdered.
She signed an affidavit saying she was on the yacht but later recanted, telling an appeal hearing she was coerced into giving that evidence.
Neill-Fraser's legal team abandoned the evidence of Ms Vass, which they had held up as the pillar of their case, during the appeal process.
Justice Helen Wood determined evidence of forensic expert Maxwell Jones, which Neill-Fraser's legal team claimed cast doubt on the secondary transfer scenario, did not prove there was a miscarriage of justice.
She said Mr Jones' evidence conformed significantly with what the jury heard at the trial.
In his dissenting view, Justice Stephen Estcourt determined there was a "significant possibility" the trial jury might have acquitted Neill-Fraser had Mr Jones' evidence been before it.
The High Court action challenges the judgment on three grounds, including that the court erred in holding that there had not been a substantial miscarriage of justice.
" ... there was no rational basis to reject the conclusion that Meaghan Vass had been on the Four Winds at the relevant time," it reads.
Neill-Fraser is eligible for parole in August but her supporters have indicated she will not leave prison unless her conviction is overturned.
Tasmania's former premier Lara Giddings, who was attorney-general when Neill-Fraser was found guilty, is among those calling for an independent inquiry into the conviction.
"We do have our legal system get it wrong and it has got it wrong in (Neill-Fraser's) case," she said in November.
Neill-Fraser has previously had an appeal rejected by the High Court.
She was found to have attacked Mr Chappell and dumped his body in Hobart's River Derwent but has maintained her innocence. Mr Chappell's body has never been found.
© AAP 2022