A murderer who got into bed between the body of the man he killed and his victim’s still-sleeping girlfriend has been denied a final appeal against his life prison sentence.

Jiaxin “Max” Tu had a long-standing jealous obsession with his flatmate’s girlfriend.

In the early hours of July 1, 2015, he went into the bedroom of the Auckland house where the couple were sleeping and bashed his flatmate, Shane Paul Hawe-Wilson, 19, in the head repeatedly with a builder’s hammer.

The young woman, who was 17 years old, did not wake up and realise what had happened until Tu got into the bed and tried to undress her some hours later.

Tu, who was 36 at the time of the killing, was found guilty of murder and sentenced in 2016 to life in prison without the possibility of parole for 12 years.

He appealed his sentence in the Court of Appeal, arguing the sentence was unjust due to the mental illness he was suffering when he killed Hawe-Wilson. That appeal failed.

Tu has been diagnosed with schizoaffective and autism spectrum disorders. His defence of insanity was rejected by the jury at his High Court trial.

He recently sought leave to appeal to the Supreme Court against his sentence.

His counsel argued that Tu’s was a “paradigm case” in which the Supreme Court could consider whether significant mental illness, falling short of insanity, could be enough to avoid the usual life sentence for murder.

The Supreme Court, however, said the question had already been decided by another case.

In that case, Kaine Van Hemert, who killed a sex worker while he was psychotic but not insane, had a life sentence upheld, although his non-parole period was reduced.

In Tu’s case, the Supreme Court declined to hear the appeal, with the judges saying: “We do not consider that it raises a matter of general or public importance.”

Nor did they consider Tu’s sentence to be a substantial miscarriage of justice.

The courts were told earlier that Tu’s “unhealthy interest” in the young woman stretched back to 2011, when she was just 12 years old and lived near him in Panmure.

His obsession was such that Tu even tried to hire a hitman to kill the woman’s previous boyfriend.

A man testified that Tu offered him $50,000 to creep into the previous boyfriend’s Onehunga home and slit his throat “like a ninja”. The man said he “wasn’t having a bar of it”.

The young woman, who was identified in the Supreme Court decision only by the initial “C”, slept through the hammer attack on Hawe-Wilson in 2015.

Five hours later, Tu climbed into bed between her and Hawe-Wilson’s dead body.

Shane Hawe-Wilson was murdered by Jiaxin Tu. Photo / NZ Police

She woke to him trying to pull down her jeans and chased him out of the room while yelling for Hawe-Wilson to help.

It was only when she returned to the bed and saw the blood that she knew something was wrong.

In the High Court, Tu’s lawyer Peter Tomlinson said Tu’s offending was “driven by his mental illness, not by any sense of rationality”.

“But for that ever-worsening mental illness, this offence would never have happened,” Tomlinson said.

Ric Stevens spent many years working for the former New Zealand Press Association news agency, including as a political reporter at Parliament, before holding senior positions at various daily newspapers. He joined NZME’s Open Justice team in 2022 and is based in Hawke’s Bay. His writing in the crime and justice sphere is informed by four years of front-line experience as a probation officer.