Philip Polkinghorne trial: Pathologist says Pauline Hanna’s death consistent with hanging

Wednesday, 4 September 2024

Warning: The latest evidence in the Polkinghorne trial involves detailed evidence from a forensic pathologist and details suicide. Some readers may find the content distressing.

The lack of injuries to Pauline Hanna were consistent with a partial hanging, a veteran pathologist has told the court. He also said it would be quite “mind boggling” to imagine Hanna’s body had been manipulated after her death to stimulate a suicide.

“There is no evidence of a forensic pathology kind to positively support a conclusion that this deceased has been homicidally manually or ligaturally killed,” Professor Stephen Cordner said at the end of evidence on Wednesday when asked about the lack of injuries to Hanna.

The highly-experience pathologist warned the jury at the start of his evidence that what he’d be talking about would be “pretty grim” and he apologised.

Pauline Hanna was found dead in the entranceway of the Remuera home she shared with her husband on the morning of April 5, Easter Monday, in 2021. Polkinghorne has denied killing his wife.

The Crown’s case is that Polkinghorne fatally strangled Hanna before reporting her death to police as a suicide. It argues he was living a double life, obsessed with meth and in a covert relationship with an escort in Sydney.

The defence case is that Hanna tragically took her own life after being exhausted by work-related stress during the Covid-19 pandemic, but she also had a history of mental health issues. The meth and sex workers were just distractions, Ron Mansfield KC told the jury on Friday.

Pathologist called to give ‘grim’ evidence

On Wednesday, veteran pathologist Professor Stephen Cordner flew over to Auckland from Melbourne to give evidence.

A lot of what he said was covered by a suppression order as he gave evidence in relation to the general mechanics of suicide.

“We’ve seen quite a lot of distressing things in this case… the danger is people may see these pictures and be vulnerable to suicide,” Justice Graham Lang explained to the jury.

The two pathologists called during the Crown case said they could not conclude whether Hanna died by hanging or as a result of being strangled, either manually or by the use of a ligature.

The disappearing mark has 'no significance'

In Dr Kilak Kesha’s evidence on August 13, he told the court he noticed a woven impression on the right side of Hanna’s neck. The following day, when he conducted the autopsy, it had disappeared. Polkinghorne had told police he found his wife with a belt.

On Wednesday, Professor Cornder said, in his opinion, the disappearing mark had 'no significance'.

Defence lawyer Ron Mansfield KC asked if the absence of the belt impression all the way around the neck ruled out an incomplete hanging.

'I don’t think so,' Cordner said.

He said it wasn't uncommon in hangings for there to be no mark.

Mansfield asked how the disappearing mark might be significant.

'The disappearing mark has no significance,' Cordner said.

'I don’t think it really does help with time of death.'

The professor said he'd read literature that cautioned about marks disappearing after death.

'Pressure marks may disappear several hours later following the removal of the ligature,' Cordner said.

'It really is quite mind boggling'

Professor Cordner was asked if the belt mark could show it had been used in a manual or ligature strangulation.

'That's absolutely out,' the professor said.

'There would have been differential movement between the ligature and the skin…there's none of that.'

The professor pointed out there were no abrasions on Hanna's neck.

Mansfield asked if the impression could have been caused by leaving it after Hanna had died.

Cordner said the people in the court would need to imagine what it is like to manipulate a dead body to stimulate a hanging, perhaps by sitting the dead person in a chair to recreate 'this sort of thing'.

'It really is quite mind boggling.'

Cordner said it takes two people to really successfully and easily handle a dead body.

Injuries present in about 70% of manual or ligature strangulation deaths

Cordner was asked about the difference between death by hanging and manual or ligature strangulation.

There are often no injuries associated with death by hanging as the person often wants to die, Cordner said.

The professor said in about 70% of cases of manual or ligature strangulation causing death, there is the likelihood of a more sustained assault before death and injuries show that.

“The resistance might result in injuries to themselves as they scrape away trying to remove hands, ligature and can cause scratches to their own on the neck. They might actually cause injuries to the assailant to try push away… scratch on the face, scratch on the wrists and hands of the assailant,” Cordner said.

Cordner said for the other 30%, when there wasn't a sustained assault, there were usually very good reasons for the lack of injuries - such as natural disease, heart disease, previous stroke, cancer, easily overwhelmed by an assailant and their age. He referenced the case of an 11-year-old who had been drugged beforehand.

Injuries present could possibly explain incomplete hanging, pathologist said

In regards to this case, Mansfield took through the injuries to Hanna’s body. He asked the pathologist if the non-specific injuries present could be a reasonable explanation to show an incomplete hanging.

'There is nothing incompatible in my view with the presence of injury and the conclusion of an incomplete hanging,' the professor said.

Mansfield asked about the absence of injuries in regards to homicidal manual or ligature strangulation and if that was important in this case.

Cordner said it was.

Mansfield said all Hanna's acrylic nails were present and they weren't dislodged to indicate a struggle or a fight. Cordner agreed.

'If there had been a fight…accords with common sense, there hasn’t been any great disturbance of those nails,' Cordner said.

Mansfield asked if there were any clear defensive injuries on Hanna.

Cordner said it didn't appear so and Dr Kilak Kesha and Dr Martin Sage also didn't see any.

In both homicidal manual and ligature strangulation, neck injuries are expected to be seen, Cordner said. This wasn’t the case here.

“There is no evidence of a forensic pathology kind to positively support a conclusion that this deceased has been homociadally manually or ligaturally killed,” Cordner said at the end of Wednesday when asked about the injuries or lack thereof.

The trial, before a jury and Justice Lang, continues with the pathologist’s evidence on Friday.