A woman accused of being an accessory to the murder of Tyson Timothy Clark-Robertson has pleaded guilty.
Renae Lorraine Donald, 21, was scheduled to appear in the Launceston Supreme Court for preliminary proceedings on Tuesday, but her lawyer Mark Doyle told the court she was in a position to enter a plea.
The Mayfield woman was charged with being an accessory after the fact to the murder of her ex-boyfriend.
She cried as she stood in the dock and entered her guilty plea.
Mr Clark-Robertson was last seen in July 2016, nearly nine months prior to police discovering his remains in a shallow grave in the backyard of a Mayfield house.
Ian Rosewall, of Mayfield, was in custody over the murder of Mr Clark-Robertson when he sought a report from a psychologist and, despite knowing privilege had been waived, he admitted to killing Mr Clark-Robertson with a hammer.
He also changed his not guilty plea to guilty last week.
Donald knew her current boyfriend Rosewall killed Mr Clark-Robertson between July 2016 and April 2017, but she kept the information secret.
A third person, Robert William Broad, was also charged over the murder.
Broad denied knowing Mr Clark-Robertson's body was buried in his backyard despite police tapes revealing Rosewall told him where it was.
In November, Broad was found guilty by a jury of failing to report the killing of Mr Clark-Robertson.
Rosewall, Donald and the victim moved into Broad's Mayfield house in the same month Mr Clark-Robertson went missing.
Rosewall and Donald have been remanded in custody.
Justice Robert Pearce adjourned Donald's matter until March 20 for sentencing.
Donald said "be there" to her supporters in the courtroom in reference to her sentencing date.
Mr Clark-Robertson's dad was in the courtroom for the plea.