Ben Wardlaw, 40, was sentenced to 22 years' jail with a non-parole period of 17 years at the Supreme Court in Ballarat on Monday.

In sentencing, Justice Rita Incerti said the murder of Ms Ashcroft, 52, was a 'spontaneous', 'drug-induced' act.

"Unfortunately, like many drug users who appear before the courts, you were foolish enough to think you could use illicit drugs without any harmful consequences," she said.

Wardlaw stabbed Ms Ashcroft, 52, in the heart with a hunting knife in May 2018 as she left a property with a friend after a gathering.

Justice Incerti told the court she was satisfied Wardlaw was suffering from paranoia and drug-induced transient psychosis at the time of the murder.

"I am satisfied your actions on this occasion were a severe departure from your usual behaviour," she said.

"You have no history of violent and aggressive conduct when intoxicated."

The court heard Wardlaw had been using prescription drugs in excess and methamphetamine and was unable to sleep properly for 10 days leading up to the crime.

He had been living in a one bedroom unit in Maryborough with five other people for two weeks. The court heard Ms Ashcroft had arrived at the unit with a friend for a gathering and was not known to others at the unit, including Wardlaw.

Wardlaw did not speak to Ms Ashcroft at any stage during the night, but was seen staring at her and was described as quiet, agitated and withdrawn.

The court heard at 3.40am on May 14, 2018, Wardlaw took a step toward Ms Ashcroft and swung the knife suddenly into her chest when she attempted to leave the gathering.

WATCH THE VIDEO OF MS ASHCROFT'S SISTER OUTSIDE COURT BELOW

She said Wardlaw's actions on the night of the murder were 'completely out of character'.

"I accept that you were not aware that by taking drugs your judgement would have been so affected that it would affect your ability to exercise self-control," Justice Incerti said.

"The community must understand the behaviour you have engaged in is denounced by the courts... particularly given you chose to use drugs that caused you to become violent and psychotic.

"The use of illicit drugs and methamphetamine in particular is a scourge on the community."

The court heard Wardlaw told a psychologist he used drugs because they were 'fun' but also said the drugs helped him alleviate or suppress negative emotions.

Wardlaw had never been admitted to a psychiatric ward or had contact with mental health services, and had never engaged in counselling, detoxification or rehabilitation for substance abuse.

The court heard his drug use began at 14 and he was expelled from school in Year 10 because he asked other students to source cannabis for him.

He worked two seasonal jobs between 16 and 18 but has no other employment history due to his drug addiction.

Justice Incerti said Wardlaw has had anxiety and panic attacks since he was 21 and has experienced chronic suicidal ideation.

Justice Incerti said she agreed that Wardlaw's crime was lower than mid-range seriousness, due to the lack of premeditation or planning, the absence of prior threat, the single stab and the fact the knife was already in his possession.

She said she also took into account victim impact statements from Ms Ashcroft's family.

"The lives of Ms Ashcroft's loved ones have been marred forever," Justice Incerti said.

"They speak as one of their feelings of grief, anxiety, depression, anger, loss of trust in others and loss of enjoyment in work and social life."

Ms Ashcroft's family said they were relieved by the sentence and they could now move on with their lives.

"We got the justice we need for my sister," Ms Ashcroft's sister said outside court.

"So I am glad it's all over and we can move on now and we can remember all the good things and not the bad."

A Supreme Court jury found Wardlaw guilty of Ms Ashcroft's murder in October, 2019.

Wardlaw has already served 658 days of pre-sentence detention.

The maximum penalty for murder is life in prison and the standard sentence for the charge is 25 years' imprisonment.

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