NZ doctor murder trial: Pathologist can't completely rule out possibility socialite did it herself

Maureen Boyce was found dead in her Brisbane apartment in 2015. Photo / Newscorp

The forensic pathologist who examined the body of Maureen Boyce cannot completely rule out the possibility the arthritic Australian socialite stabbed herself with her wrong hand so hard the blade went through her back.

But Professor Beng Beng Ong told the Brisbane Supreme Court he favoured the probability the wounds to the 68-year-old former model were caused by a "second person".

New Zealand-based doctor Thomas Christopher Lang is on trial after pleading not guilty to murdering Boyce at her Kangaroo Pt apartment in October 2015.

On Wednesday, the jury was shown photos of the 32cm knife embedded so deeply in Boyce's abdomen that part of the handle was inside her body. The tip of the knife was also found to be protruding from her back.

Ong said the blade was thrust into Boyce twice, partially withdrawn and turned then plunged into her another two to three times.

The court heard the injuries would have been "fairly painful" for the mother-of- two before she bled to death.

"I'd probably favour that it was probably caused by a second, different person," Ong said.

"Having said that I cannot rule out completely that it can be self-inflicted."

The court has heard Boyce, who was right-handed and suffered from arthritis in her fingers, was found touching the knife with her left hand.

Crown prosecutor David Meredith has told the jury they must decide whether Boyce took her own life or if she was killed by Lang in a "jealous rage".

In a triple-zero call played to the court last week, Lang said he found Boyce dead after she had been "upset" the night before and told him to sleep at the other end of the apartment.

"I just woke up this morning and I found my fiancee dead in her bed with a knife in her abdomen," Lang said.

"There's been no forced entry, it looks self-induced."

The court has heard Lang and Boyce fell in love in the 1980s when they met in Texas before she returned to Australia alone to give birth to a son.

The pair then reconnected in June 2013, and Lang claimed they were secretly engaged at the time of Boyce's death despite her telling friends and family she wanted him to leave.

The court has heard Boyce struggled with mental illness, including bipolar disorder, for many years, and was stressed about the sale of her sub penthouse.

- NZN