He also questioned whether such cases should be decided by a jury.
These factors were among the grounds on which an appeal could be launched he said.
Waipapa Taumata Rau - University of Auckland law professor Julia Tolmie said it is impossible to predict what sentence Dickason will get at this point and it could all depend on “how compassionate the judge is”.
She said it is typical in cases where a murder is “particularly egregious” to set a minimum non-parole period of at least 17 years.
She said that was what Gallavin was referring to when saying the minimum sentence could go as high as 30 years.
“[Dickason] ticks three of the criteria for a minimum non-parole period of 17 years or more,” Tolmie said.
These included that Dickason’s victims were underage, young and vulnerable, there were three killings, not just one, and the killings were “particularly cruel and brutal”, she said.
The question then centres on whether Dickason’s mental health issues make the minimum non-parole period manifestly unjust, Tolmie said.
While the legal case is strong for a long non-parole period, Dickason appears to be someone with “extreme mental health issues”, Tolmie said.
“And prison is not a great place to get treatment for mental health issues.”
Te Herenga Waka-Victoria University of Wellington lecturer Danica McGovern said it was also not a guarantee that Dickason may even escape getting a life sentence because of her mental health issues.
“A sentence less than life imprisonment can be imposed where the offender’s blameworthiness is significantly reduced by serious mental health problems - it’s rare, but the judge will need to decide if that’s the case here,” McGovern said.
“If a life sentence is imposed, Dickason’s depression and the major life stressors she was experiencing in the lead-up to the murders will be taken into account when deciding how long she must serve before she can apply for parole.”
Killer’s parents: ‘This was not our daughter’
Dickason’s parents Malcolm and Wendy Fawkes and the extended family released a statement to media after the verdict.
“Postpartum depression is a terrible thing, as has been shown by what happened to our family on 16 September 2021.
“This was not our daughter, but a debilitating mental illness which resulted in an awful tragedy, the details of which you are by now well aware.”
They said Liane, Karla and Maya were “taken from this life to another as a result of this crippling disease”.
“We would like to thank the people of New Zealand, South Africa and from around the world who have been so understanding of the effects of postpartum depression and mental illness, and who have given us incredible support.
“The New Zealand Government agencies who have interacted with our family have reached out to us in a most generous and compassionate way. We thank the good people of New Zealand for that.”
They said there are “no winners in this tragedy”.
“We would like to encourage families and individuals around the world to be aware of the symptoms of postpartum depression as early as possible, both for yourselves as well as close family and friends around you.
“If treated early and managed correctly, people can experience a full recovery. The person experiencing depression and those closest to them may not be able to recognise the signs or how serious postpartum depression can become.”
Detective Inspector Scott Anderson said: “Words cannot begin to express the tragic circumstances of this investigation”.
Police extended their deepest sympathies to the families “who will never get to see Liane, Maya, and Karla grow up and live their lives”.
“I would like to acknowledge the Dickason and Fawkes families who have assisted us throughout our investigation,” Anderson said.
“I also want to take this opportunity to acknowledge the hard work and dedication of our investigation team.”
Anderson said the investigation had been challenging and complex.
“Right from attending the scene on the night, to the completion of the trial, and through it all our staff have worked diligently with professionalism and empathy to bring this matter to its conclusion.
“Our heartfelt thanks also to the Timaru community and partner agencies who have continued to provide support to the families during this case.”
Judge Cameron Mander yesterday told the jury he would accept a majority verdict.
Just after 3pm yesterday, the jury, who had been deliberating since early afternoon on Monday, indicated they had reached a verdict.
Earlier, the jury indicated they had a question and returned to court soon after.
Justice Mander was told the jury had been unable to reach a unanimous verdict and asked for instruction.
In criminal cases, after a jury has deliberated for at least four hours and has not reached a unanimous verdict the judge may instruct them to consider a majority verdict, which is agreed to by all except one juror and can only occur if the foreperson states in open court there is no probability of the jury reaching a unanimous verdict, as the Juries Act stipulates.
The eight women and four men - selected on July 17 - retired at 1.55pm on Monday after Justice Mander gave a lengthy summing up of the case against Dickason - and her defence.
Guilty of the lesser alternative charge of infanticide
Murder proven but not guilty by reason of insanity
Infanticide proven but not guilty by reason of insanity
Justice Mander said there was no doubt Dickason killed the little girls and that she was very mentally unwell and he spent much time talking them through each.