Prosecutors had alleged the retired eye surgeon had strangled Hanna, 63, on the morning of April 5, 2021, before staging the scene to look like a suicide. Much of the trial focused on Polkinghorne’s methamphetamine use, his extravagant spending on sex workers and his alleged “double life” with Sydney escort Madison Ashton.
The defence, meanwhile, focused on Hanna’s mental health and the findings of four pathologists - none of whom could point to definitive evidence of homicidal strangulation. She committed suicide just as the widowed defendant maintained from the time he called 111, they argued.
Jurors, who deliberated for about 10 hours over two days, sent out a note several hours before their verdict saying “most” did not believe the defence contention Hanna committed suicide. But “some” on the jury did not think the Crown had proved beyond a reasonable doubt that Polkinghorne intentionally strangled her, the note also said. The jury’s unanimous not-guilty verdicts for both murder and manslaughter a short time later indicated those who had doubts went on to convince the rest.
The GP, who saw Hanna from 2009 until her death 12 years later, spent two days in the witness box as defence lawyers Ron Mansfield KC and Hannah Stuart suggested in not subtle terms that her prescribing practices were partially to blame for Hanna’s alleged suicide.
The doctor, riled at the suggestion, insisted she did nothing out of the ordinary.
Hanna had been prescribed anti-depressant Prozac since 2001, eight years before the doctor who gave evidence became her GP. She had also been on prescription appetite suppressant Reductil for five years - again under her previous doctor - until it was taken off the market in 2009.
The doctor who gave evidence helped her replace that prescription with a similar drug, Duromine, in 2010. The amphetamine has clear prescribing instructions, which include only giving it to people who are obese, with regular weigh-ins and for no more than three months at a time, the defence noted repeatedly. Hanna continued to take the drug for over a decade, until her death.
“Most women, especially going through menopause ... they have heightened awareness of their weight,” the doctor testified, adding she would prescribe the drug to any patient in that situation who asked for it. “I didn’t find it very unusual. She really wanted to continue taking medications to maintain her weight.”
The defence pointed out there had been occasions where other doctors noted the length of Hanna’s use and suggested she should be weighed to see if usage should continue.
“That didn’t cause you to think, ‘Hold on, maybe I should stop and have a think about this?’” Stuart asked.
The doctor said no.
“I’ve never seen anyone who has abused Duromine,” she said. “She was okay on this medication. She didn’t have any side effects of the medication.”
But other medical experts called by the defence suggested the medication was inappropriately prescribed.
During his closing address a month later, Mansfield argued Hanna’s suicide risk had been increased by her use of the prescription drug along with her “regular consumption of alcohol in harmful quantities”.
“It’s a medication that she never should have been on, she never qualified for it and if she was on it, she should have been only on it for a period of three months and that monitored,” he said. “And she certainly should not have been on it for that length of time, given how dangerous it is, as far as impacting on an individual’s mental health.”
Crown solicitor Alysha McClintock disagreed the long-term prescription made Hanna suicidal. The fact she had been on the drug for over a decade with no known side effects suggests she was well-maintained, she said. But McClintock didn’t go as far as endorsing the doctor’s approach to treatment.
“I’m not here to defend the prescribing practice,” she told jurors. “It’s not intended to be prescribed in the way that it was, but that’s not the issue that’s before you.
“Whatever the papers say about the risks of this, the evidence is that Duromine seemed to be helping her state of mind, which in turn helps, obviously, her mental health. She looked good, she felt good. If she’s going to experience side effects from Duromine, they would most likely occur when she first started to take it.”
The defence also suggested the GP failed to provide adequate follow-up support after Hanna called her to report suicidal ideation on December 23, 2019 - while Polkinghorne claimed in a letter to be at a men’s retreat contemplating their marriage but had instead travelled to Sydney to spend Christmas with Ashton.
Hanna was referred to a crisis team after saying she had contemplated driving into a truck on her way to the couple’s Coromandel bach. The suicidal thoughts did not result in actual plans, Hanna said at the time, in part because she thought of her family.
During a follow-up call with the GP the next day, Christmas Eve, Hanna said she was feeling better and had been in touch with the crisis team, the witness recalled, adding the patient did not want any more help on the matter. The doctor said she would have likely heard back from the crisis team had the issue not been resolved, but the lack of communication gave her assurance.
She didn’t see Hanna in person for the next 15 months before her death, although much of that time was during the Covid-19 pandemic, when routine doctor’s visits would have been curtailed.
Before his murder trial, Polkinghore filed a formal complaint against the doctor with the Health and Disability Commissioner. However, the commissioner has opted not to determine the complaint until after the completion of a coronial investigation. The coronial investigation hasn’t been conducted yet because the jury trial took precedence.
An in-chambers coronial review hearing is currently scheduled for December.
The GP had sought permanent suppression but was instead granted temporary suppression while testifying, with permanent suppression to be addressed after the trial. But rather than making a definitive decision with today’s judgment, Justice Lang left the door open for either option.
The Crown had been neutral on her request for permanent suppression but Polkinghorne’s lawyer opposed it.
In court documents filed before her trip to the witness box, the doctor said she feared her reputation would be considerably damaged, causing undue hardship. She had no right to call evidence on her own behalf at the murder trial, she noted.
She pointed out that most doctors subjected to a Health and Disability Commissioner complaint are allowed to keep their anonymity until at least the conclusion of the investigation process - and often permanently.
Justice Lang said he was satisfied that if the doctor’s name was to be revealed now, “members of the public are likely to conclude that her actions fell below required professional standards”. But whether that conclusion would be fair is another issue, he said.
“The commissioner has specialist expertise in determining whether conduct of a particular type falls below the threshold required of a reasonably competent medical practitioner,” the judge noted. “The jury in the present case did not have such specialist expertise, and in any event that issue fell well outside the range of issues the jury was required to decide.”
If the doctor is allowed to keep her identity secret by the commissioner at the end of that investigation, the suppression of her name will also become permanent regarding her trial testimony, Justice Lang decided. If the commissioner allows her name to be published, temporary suppression will remain in place until any legal challenges have been exhausted, he said.
Craig Kapitan is an Auckland-based journalist covering courts and justice. He joined the Herald in 2021 and has reported on courts since 2002 in three newsrooms in the US and New Zealand.
The Herald covered the case in a daily podcast, Accused: The Polkinghorne Trial. You can follow the podcast at iHeartRadio, Apple Podcasts, Spotify, through The Front Page feed, or wherever you get your podcasts.
