"I looked into their eyes, saw fear, and pulled the trigger."

It was 1960s New Zealand, and Shaun* was a contract killer. He was young, only a few years out of school, and had quickly fallen in with the wrong crowd.

He had been initiated into a gang, and was soon called on to "take care" of a few people who had ended up on the wrong side of his leaders.

He didn't know much about them, sometimes he didn't even know names. But he knew their faces. He saw the fear and the anguish and the struggle as they died in front of him. He took the money he was paid, and he took their lives.

CATHERINE REISS/STUFF A soon to be published paper by researchers at Auckland City Hospital and Auckland University's Medical and Law School discusses the legal and ethical implication of not disclosing death bed confessions to police.

That was 50 years ago. The murder cases for the contract killings Shaun said he committed were never solved. It's very likely some of the bodies were never found.

Shaun died in 2018 from cancer.

The secret would have died with him, but for a sudden urge to confess in his last days. Lying in bed at Auckland City Hospital, in immense pain and aware that he was not long for this world, he called a member of his palliative care team to his side and and told them he needed to get something off his chest.

The guilt had been eating at him his entire life.

The doctors Shaun confided in promised to keep everything he said between them. Police have not been informed.

A soon to be published paper by researchers at Auckland City Hospital and Auckland University's Medical and Law School discusses the legal and ethical implication of the decision.

The families of Shaun's victims may still be out there, still seeking the closure they will likely never get.

GETTY IMAGES Shaun confessed his past as a contract killing while being treated for cancer at Auckland City Hospital.

The clinical team reported a significant improvement in Shaun's pain levels and wellbeing after his confession.

"As he talked he had a remarkable transformation, becoming calm and measured with obvious relief showing in his voice and body language."

He was in palliative care, meaning he was terminally ill and the clinical team was focused primarily on reducing pain levels and providing comfort before death.

Before the confession, he had been in too much pain to walk or even eat. The next day he was able to do both, and over the next week he required significantly less painkillers.

When there is not much time before a patient's death, therapeutic and spiritual work can be some of the most effective strategies in terms of reducing pain and helping patients make peace with their lives.

In Shaun's case, it resulted in "relief of both his physical pain and anguished medical state," according to the clinical team.

SIMON MAUDE/STUFF After a few years working as a hired gun, Shaun was charged and sentenced with the comparatively minor crime of accessory to murder.

At the time he made his confession, Shaun likely thought he would die within days or even hours. But after he got it off his chest, he made a surprising recovery - so much so in fact that he regained enough strength to be discharged from the hospital into a nursing home.

Doctors had assured Shaun that his confession would not be disclosed unless he was at risk of doing himself or someone else harm, but the weight of his confession naturally made them "uneasy".

Urgent legal opinions were sought from their personal liability insurers and from the hospital asking whether the confession could be revealed to police. The advice came back with conflicting opinions, and the clinical team ultimately decided it would not be appropriate to inform the police.

At the same time, Shaun was encouraged to write down his confession so it could be given to police after his death, which he agreed to do, though he said he didn't want help and would do it on his own. The staff don't know whether he ever wrote or sent the letter.

CHRISTEL YARDLEY/STUFF Medical ethicist Phillipa Malpas argues that doctor-patient confidentiality was a cornerstone of effective medical practice, and that Shaun's therapuetic treatment, which demonstrably reduced his pain levels, was only possible because he has trust and confidence that his doctors would not disclose the information to anyone else.

A police spokesperson said they were not aware of any recent filings that fit the description.

The clinical team said they made the decision based on balancing the likelihood of harm versus the likelihood of benefit.

They came to the conclusion that there was very little to gain from telling police, simply because Shaun was going to die soon, and because the crimes happened so long ago. If the murders had been recent, or Shaun had indicated desire to "make good" through official channels while still alive, the outcome may have been different.

Medical ethicist Phillipa Malpas argued that doctor-patient confidentiality was a cornerstone of effective medical practice, and that Shaun's treatment, which demonstrably reduced his pain levels, was only possible because he has trust and confidence that his doctors would not disclose the information to anyone else.

It would be a breach of confidence to inform police while Shaun was still alive - he very well may have denied the allegations, and then the team would be left with a dying patient who no longer trusted his carers.

But presuming he had never written the letter to police, she argued, it would be "ethically permissible" for doctors to now, after his death, inform the police of his confession.

"Given the seriousness of the crimes he committed and the harms suffered by others as a result, the moral obligation to disclose the information to the police should take precedence over any possible diminution of [Shaun's] memory."

Police have urged the doctors or anyone else with information to get in touch, saying: "Any new information brought to our attention will be assessed and dealt with appropriately."

But whether the doctors even legally can tell police is contentious, though Professor Jo Manning of the University of Auckland Faculty of Law believes they could.

The disclosure of his confession would cause "significant harm to his memory and distress to his surviving family and friends" she said, and if he had requested that the information be kept secret, then they would have an obligation not to tell anyone.

However, the public interest in a proper police investigation would override that, she said. While Shaun was not at risk of reoffending, and there is obviously no opportunity for sentencing now that he has died, it would provide closure to the victims families to know the identity of the perpetrator and the location of the bodies. It would also be a strong deterrent to others to show that perpetrators are held to account, no matter how long it takes.

Manning said that the clinical team were "permitted, but not obliged" to go to the police. As of now, they have decided to hold fast and stay silent.

When asked for comment, a DHB spokesperson said: "Auckland DHB leadership learned of this incident today. The individual doctors involved did not consult us as part of their decision-making process which is a question of professional medical ethics.

"Without access to details of the matter we are not able to comment on their decision not to disclose the information to the police. While patient confidentiality is central to healthcare, Auckland DHB leadership also takes any risk of harm to the wider public very seriously."

For Shaun keeping quiet about what he'd done wasn't easy.

After a few years working as a hired gun, he had been charged and sentenced with the comparatively minor crime of accessory to murder. Considering what he could have faced, it was a slap on the wrist.

After being released from prison, he turned away from a life of crime and sought a fresh start in the Merchant Navy. But it didn't help - there again, he was forced to kill people to protect his boat and fellow crew from pirates.

After returning to home to New Zealand, he spent the next 40 years of his life trying to atone for what he had done.

He donated huge amounts of money to charitable organisations, volunteered for good causes, and took in "lost souls" to provide shelter and help, guidance, and help them turn their lives around.

As he unburdened himself of his crimes to his doctors he reflected on his situation.

"The problem for me is now someone else has the gun and I am the one who is afraid. I always pulled the trigger first - but now I can't."

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