Bonnie Sawyer-Thompson barely knew the man she hacked to death with an axe.

The then-19-year-old was in an ice-addled state when her abusive boyfriend, Phil Mifsud, ordered her to kill the victim.

He threatened to murder her family if she didn't carry out the monstrous crime.

She stabbed Jack Nankervis 70 times in her Morwell flat in June 2014.

Sawyer-Thompson was initially charged with murder, but the Director of Public Prosecutions later agreed she could plead guilty to the lesser charge of defensive homicide.

The charge was abolished shortly after the killing, making Sawyer-Thompson the last person in Victoria to be prosecuted under this law.

Bonnie Sawyer- Thompson was 19 when she hacked Jack Nankervis to death in 2014.

Bonnie Sawyer- Thompson was 19 when she hacked Jack Nankervis to death in 2014.

It was intended for women subjected to ongoing domestic violence who retaliate against their abusive partners.

This case was noted as unique and the most grave example of defensive homicide, as the threat did not emanate from the victim, but rather a person who was absent during the killing.

Mr Mifsud had left the home while Sawyer-Thompson’s attack on Mr Nankervis took place to ensure he had an alibi, but later reported the discovery of the victim's body.

He has never been charged.

The court heard he subjected Sawyer-Thompson to humiliation and violent abuse, including putting a gun to her head and forcing her to swallow bullets.

Sawyer-Thompson has been sentenced to ten years' jail.

Sawyer-Thompson has been sentenced to ten years' jail.

Sawyer-Thompson's boyfriend, Phil Mifsud.

Sawyer-Thompson's boyfriend, Phil Mifsud.

He had also previously injected her with drugs and put firecrackers down her top.

In sentencing at the Latrobe Valley Law Courts today, Justice Michael Croucher said Mr Mifsud’s influence on Sawyer-Thompson did not entirely mitigate her actions.

"Plainly she meant to kill him and she did,” Justice Croucher said.

“It was merciless, grisly and disturbing.

"Mr Nankervis was in a drug stupor and completely defenceless at the time."

Mr Nankervis' family wore green ribbons, his favourite colour, to court and wept as they heard the gruesome detail of his death.

Mr Nankervis' mother, Anna, spoke outside court.

Mr Nankervis' mother, Anna, spoke outside court.

His mother, Anna Nankervis, outside courts said it was a "disgrace" the defensive homicide charge was able to proceed.

Mrs Nankervis said and the past three years had been "horrific … you couldn't imagine.”

“You can't say your son died or passed away, you have to say he was murdered,” she said.

"He was one in a million, (I’ll) never get another Jack."

They stared at Sawyer-Thompson in the dock as she was sentenced to ten years’ jail.

With time already served, she could be eligible for parole in just four years.

© Nine Digital Pty Ltd 2017

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