Key witness in Sue Neill-Fraser's murder appeal, Meaghan Vass, abandons testimony

Meaghan Vass told the Supreme Court on Monday she was onboard the Bob Chappell's boat in Sandy Bay with two men the night he disappeared.

Director of Public Prosecutions Daryl Coates on Tuesday raised Can inconsistency with Vass' evidence from Monday when she mentioned a third man on the boat.

She said the third man was an associate of the two men who were on the boat.

"I made a mistake," Ms Vass said. "I suffer from anxiety. I'm really not coping. I'm doing my best."

Mr Coates later put it to Ms Vass that two of the men she had named in Monday's hearing were not on the boat and she had been told to say that they were.

"Yes," Ms Vass repied.

"Is it the case you have no memory of being on that boat at all?" Mr Coates asked.

"Yes," Ms Vass said.

She said she had been told to name the two men by a woman who cannot be named due to a suppression order from the court.

The witness key to Susan Neill-Fraser's appeal hearing has told court she was onboard Bob Chappell's yacht the night he disappeared, but the convicted killer was not.

Neill-Fraser is serving 23 years' jail for the murder of Mr Chappell, of which she has served more than a decade.

Meaghan Vass appeared briefly by videolink in the Hobart Supreme Court on Monday morning for the first day of a week of hearings.

She was asked by Neill-Fraser's senior defence counsel, Robert Richter, if she was onboard the Four Winds yacht the night Neill-Fraser's defacto partner Bob Chappell disappeared on Australia Day 2009, to which she replied "yes".

The hearing was adjourned early on several occasions to allow Ms Vass to seek legal advice on her giving evidence.

Justice Helen Wood, who is part of a panel overseeing the hearings with Justice Robert Pearce and Justice Stephen Estcourt, explained evidence given by Ms Vass in these proceedings could not be used against her in other proceedings.

But she said if Ms Vass provided false statements to the court, action could be brought against her in these proceedings.

In his opening remarks, Mr Richter said there were two central issues to Neill-Fraser's appeal case: whether Ms Vass was onboard the Four Winds the night Mr Chappell disappeared and whether Neill-Fraser was also onboard and played a role in the disposal of his body.

"There is, as we say, one witness that can answer these questions and that is Megan Vass," he said.

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