The trial has been intense - from the harrowing evidence of a still-grieving father to the extensive expert evidence and subsequent cross-examinations.
Once the expert evidence is complete - the jury will hear from five psychiatrists in total - the Crown and defence will both deliver closing addresses.
The presiding judge will then sum up the case in its entirety and send the jury to deliberate.
That is expected to happen by about midweek.
If found guilty of murder, Dickason faces life in a New Zealand prison.
If the jury find the insanity defence is proven, Dickason could spend the rest of her life in a psychiatric unit in Christchurch.
The judge will instruct the jury on exactly what information it should consider to reach a verdict.
In the third week of trial, here is what the court heard:
Monday, July 31
Defence expert witness Dr Susan Hatters-Friedman - a forensic and reproductive psychiatrist - was cross-examined at length by the Crown about her opinion.
“It is my opinion that at the time of her alleged offending Lauren Dickason was labouring under a disease of the mind to such an extent that it rendered her incapable of knowing that the act was morally wrong. She conceptualised that [killing the children] was the right thing to do.”
Prosecutor Andrew McRae grilled Hatters-Friedman on her interactions with Dickason that only occurred this year and questioned her conclusions.
Graham Dickason reportedly wrote to his wife saying he could not understand how the alleged murders had happened
Dickason wrote a letter, said McRae, saying she had “difficulty understanding his lack of understanding” given he had “been there with her all through it”.
Tuesday 1
Forensic psychiatrist Dr Erik Monasterio continued to give evidence for the Crown for much of the day before telling the jury what his own formal findings were about Dickason.
He spent almost nine hours interviewing her and assessed all available information about her and her case from police, doctors, witnesses and her family. He - like the other experts - also sat in on the trial each day to get an even deeper insight into Dickason’s case.
While Monasterio accepted Dickason had a “disease of the mind” and was experiencing a depressive episode when the girls died, he did not believe it was severe and he was not convinced she was insane at any time.
In his opinion, there was no evidence of psychosis or delusions.
“She systematically strangled the children and seemingly methodically checked for vital signs before resorting to smothering them until they were dead,” he said.
“The alleged offences are unlikely to have been impulsive. In my opinion… there is no evidence that she was in an automated state or that she did not understand the nature and quality of her actions at the material time.
“The defendant’s mood and anxiety disorder does not appear to have caused such significant cognitive impairment that she was rendered incapable of understanding the moral wrongfulness of the alleged offences.
“Therefore, on the balance of probability, in my opinion, the defendant does not have an insanity defence… The balance falls quite heavily against the defence of insanity.”
He said there was also no way the accused could rely on a defence of infanticide.
Infanticide is when a mother kills her child due to a mental disturbance that directly results from giving birth.
Monasterio said Dickason’s mood disorder was diagnosed at 15 and had “recurred and relapsed” and was not related to pregnancy or childbirth.
“The depression was already there before she gave birth so it cannot be called postpartum,” he said.
“It is likely that the effects of pregnancy and adaptation to the demands of motherhood and the care of three young children contributed too, but did not fully account for the defendant’s major depressive disorder at the time of the children’s birth.
“There is no evidence the defendant has an infanticide defence available.”
Wednesday 2
Much of the day was Monasterio being cross-examined by the defence.
His findings were critiqued and questioned and it was put to him that he “did not like” Dickason and his conclusion was “biased”.
It was also suggested that he did not have “a good rapport” with the accused and she was distressed after each interview. Given that, he was not able to get the full picture of her mental health and the offending from her.
Monasterio refuted the defence claims and stood by his findings. He acknowledged there was some information he had not included in his final report but assured the jury he had considered everything put before him and his opinion was both complete and sound.
She is a consultant psychiatrist at Hillmorton Hospital for Te Whatu Ora Waitaha Canterbury and her experience lies in the oversight and treatment of some mentally disordered offenders admitted there.
McLeavey first interviewed Dickason six days after the alleged murders, and while the was no question the woman had a “disease of the mind” there simply was not any evidence of insanity.
“It remains my opinion that the defendant’s disease of mind did not seriously impair her reality, testing ability and capacities… such that she did not know the alleged offending was morally wrong, having regard to the commonly accepted standards of right and wrong,” she said.
“I am of the opinion that this is a tragic case where a mentally disordered woman with a vulnerable personality killed her children in the context of the situation which she perceived to be beyond her limited capacity to manage stress... in addition to underlying mental illness.
“Taking these factors into consideration, on the balance of probability, I am of the opinion, the defendant would not be eligible for an insanity defence.”
McLeavey said while Dickason had an “abnormal mental health state” she “cannot unequivocally subscribe” to the theory that the “balance of her mind was disturbed by reason of her, not having fully recovered from the effect of giving birth”.
That was partly because of Dickason’s “propensity for depression” dating back to when she was 15.
She said Dickason suffered “a relapse of depression and anxiety disturbance from mid to late June 2021″ that arose out of her life circumstances.
That exacerbated her “lifelong propensity towards anxiety and perfectionism” and “entrenched personality trait... of demanding very high standards” from herself with “the tendency towards self-criticism for any action or perceived failure to meet these standards”.
McLeavey said there was no correlation between Dickason’s “reproductive issues” and “psychological psychiatric well-being presentation”.
“It is my opinion on the balance of probability, there is no evidence that the defendant has an infanticide defence available.”
Friday 4
The trial is adjourned until Monday after a juror calls in sick.
He has been a senior Crown prosecutor and in 2007 he joined the Crown Law Office as a Deputy Solicitor-General.
He has previously presided over a number of high-profile cases including the Christchurch mosque gunman, Work and Income double murderer Russell John Tully and Elliot Prakash, who beat Christchurch woman Val Heaney to death in her own home with a hockey stick.
The prosecution
Crown Solicitor Andrew McRae has been responsible for criminal jury trials in the High and District Courts in North Otago, South Canterbury and Mid-Canterbury since 2013.
Dickason’s case was initially heard in the High Court at Timaru - the jurisdiction the alleged murders occured in - but was relocated to Christchurch given the need to detain her at Hillmorton Hospital throughout.
McRae worked for many years for the Christchurch Crown Solicitor’s office, Raymond Donnelly, and prosecuted more than 100 trials as sole counsel.
In late 2007 he joined Gresson Dorman & Co which holds the Crown Warrant for the wider Timaru region and has since led 150 trials including homicide, drug and fraud cases.
He took over the case when local prosecutors had to recuse themselves and was successful in getting convictions for rape for the two main offenders brothers Roberto and Danny Jaz.
He is assisted by senior Shawn McManus.
The defence
Dickason is represented by a team of lawyers led by Kerryn Beaton KC, who has more than 25 years of experience and a particular focus on criminal cases involving abuse and vulnerable people.
Beaton was the first Deputy Public Defender for Christchurch and was responsible for setting up the regional Public Defence Service - including training and leading a large team of lawyers.
She was appointed a Queen’s Counsel - now King’s Counsel - in 2021.
Beaton’s CV also includes work on three major inquiries outside the criminal courts.
In 2011 she was counsel assisting the Pike River Royal Commission; from 2014-16 as a legal officer in the United Nations Khmer Rouge investigations in Cambodia; and she is currently senior counsel assisting the Royal Commission of Inquiry into Abuse in Care.
Assisting Beaton is barrister Anne Toohey who specialises in criminal and civil litigation, employment law, regulatory law and health law.
Toohey worked as a civil litigator and prosecutor for the Christchurch Crown Solicitor’s Office from 2000 to 2011.
She also held the role of Crown Counsel at the Crown Law Office in Wellington for a number of years.
Barrister Abbie Hollingworth is also assisting Beaton and Toohey.
In court for the trial are police who worked on Operation Royal, the investigation into the deaths of the Dickason girls.
Dicakson’s parents have also been present in the court each day along with the expert witnesses who sit in and observe to see if there is any further information they can glean to bolster or change their formal opinions.
At times the public gallery has been full of people coming to watch the trial.