Lisa Fenwick was found on the bedroom floor of her apartment with dozens of stab wounds.

A narcissistic killer who claimed he was sleepwalking when he stabbed his partner dozens of times is poised to appeal his lengthy jail term.

The body of Lisa Fenwick was found on the bedroom floor of her Sydney apartment in April 2023, covered in a washcloth with 28 stab wounds, including to her heart and lung.

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Anthony Eriksen, who was 61 at the time, has lodged an intention to appeal his 26-year sentence, with a non-parole period of 20 years.

He told a triple-0 operator he “put a knife into her” but pleaded not guilty in court, stating he was suffering sane automatism dissociation or sleepwalking.

He sacked his defence team just prior to sentencing, representing himself at the trial, pleading “not guilty”, saying he “didn’t mean to”, and that he was suffering from “sane automatism by dissociation” — otherwise known as “sleepwalking”.

Despite being unsuccessful for Eriksen, this defence has worked before and very recently.

In 2024, Aaron Mendis successfully argued “sexsomnia”, meaning he was asleep when he had sexual intercourse with three young boys and indecently assaulted two other boys.

He was found not guilty of all counts after the court heard there was no dispute the sexual acts occurred.

Similarly, Victorian prosecutors dropped charges against Ilknur Caliskan after claiming she was asleep when she killed her husband Serdar in September 2023.

Eriksen was assessed by a health assessment team to have been in “a bright mood” and “jovial and reactive” just after executing what has been described as a stabbing frenzy.

In Australia, a person cannot be found guilty of an offence if they were unconscious or asleep when the crime was committed.

Case law shows that a defendant’s actions must be voluntary.

In Eriksen’s case, it was established he intended to kill Lisa, but the murder was not premeditated.

Neighbour and friend Jeremy Maspero said that Eriksen was “approachable, very outgoing, and happy to chat with everyone”.

At the sentencing, the court heard Eriksen was financially reliant on Lisa and couldn’t handle her ending the relationship.

Shortly before her death, Lisa told a counsellor her relationship with Eriksen had “irretrievably broken down”, and finally realised she had to leave.

She also sent Michelle Roberts, a close friend, text messages that she was fearful of Eriksen.

“If anything happens to me before, believe I am of sound mind,” she said.