Lauren Dickason murder trial: Defence accuses Crown expert witness of bias

Warning: This story contains evidence from the trial which some readers may find extremely upsetting.

Lauren Dickason's lawyer has accused a leading psychiatrist of bias when assessing the murder-accused mum.

The expert told the jury on Tuesday he found no evidence of insanity or postpartum depression when Dickason killed her three children. 

In his cross-examination on Wednesday, the defence hit back - claiming the expert didn't have a good rapport with Dickason and his mind was clouded by bias.

Over the course of the trial, the jury will hear from five mental health experts who assessed Dickason after the killings.

She is accused of murdering her little girls - 6-year-old Liané and 2-year-old twins Maya and Karla - at their Timaru home on September 16, 2021.

The children were found dead by their dad Graham Dickason after he returned home from a work function.

Lauren has admitted to killing her children by smothering them to death but pleaded not guilty to murder. Her defence is arguing insanity and infanticide - that she did not know what she was doing at the time of the killings.

However, the Crown alleges Lauren is guilty of murder, saying she was aware of her actions before, during and after the crime. 

The trial continues for its thirteenth day at the High Court in Christchurch in front of a jury of eight women and four men. 

Lauren Dickason at Christchurch's High Court.
Lauren Dickason at Christchurch's High Court. Photo credit: Pool

'You just don't like her'

The defence has cross-examined Erik Monasterio, the former director and clinical director of Canterbury District Health Board area mental health after he said there is no evidence of insanity or postpartum depression when Lauren killed her children. He has undertaken thousands of mental status examinations over his career.

Dr Monasterio previously told the jury how Lauren changed her reasoning behind killing her children six months after he first interviewed her. He questioned why somebody would say they killed their children because they were concerned serious harm would come to them.

Defence lawyer Anne Toohey questioned the different accounts given by Lauren to the psychiatrist.

"Are you saying that Mrs Dickason, in not giving the identical account, that she's lying?" Toohey asked.

"I have made clear that in my opinion, I can not tell anyone whether the defendant was lying to me at the time," Dr Monasterio replied. "What I was trying to understand were there any reasons in relation to her memory that may have accounted for the change of accounts and I have given an opinion that I could not identify any memory deficit."

Dr Erik Monasterio.
Dr Erik Monasterio. Photo credit: Pool

Toohey went on to suggest Lauren didn't have a good rapport with Dr Monasterio. She referred to a report after their fourth interview which said Dickason was "distraught" and sobbed on her bed. 

She reported wanting to see him again as she has gained more clarity over what occurred and wanted to share it with him.

"Lauren felt like she was a liar and she is insistent this is not the case. She is not angry but more frustrated that she was not believed, or at least that's how she feels," the report said.  

Toohey then accused Dr Monasterio of bias, suggesting he disliked her.

She revealed comments from Dr Monasterio where he said the text messages from Dickason reflected "someone of privilege coming to a less privileged environment" and that she was more concerned with access to home help and ironing machines than any proposed harm to her children.

"Do you think it's possible that in April of 2022, before you went to interview Mrs Dickason that you had taken a negative view of her and this might of unconsciously affected your interviewing style with her?" Toohey said.

"The issue of bias is one that troubles and challenges all forensic psychiatrists and it's one that I have front of mind. So I am aware that you have to be aware of the risk you have for bias," Dr Monasterio replied.

He continued to say how Lauren had denied violent thoughts towards her children and then revealed she had those thoughts and fashioned cable ties together back in South Africa.

"Previously she denied this to me… Now whether you can attribute that to personal bias I am not clear about that.

"I have put facts before the court. How those are interpreted will eventually be a matter for the jury."

Toohey then asked the psychiatrist "you just don't like her do you?" To which he disagreed.

Defence lawyer Anne Toohey cross-examines the Crown witness.
Defence lawyer Anne Toohey cross-examines the Crown witness. Photo credit: Pool

Toohey suggested Lauren did not tell Dr Monasterio about her violent ideations towards the children because they didn't get along. She got the impression of this from the hospital notes after the interview reporting Lauren would be tearful and distressed.

"She's not getting on with you though… that might be a reason that she might not have told you everything because she's got the impression that you're accusing her of lying," Toohey said.

However, Dr Monasterio said the way Lauren presented after the interviews was likely due to the traumatic subject matter of their conversations - not a result of their relationship.

"I can tell you without a doubt that this is traumatic and distressing information," he said.

Dr Monasterio said he would expect her to be distressed after the interviews because she is discussing the deaths of her children.

Is Lauren psychotic?

Dr Monasterio told the jury if Lauren's psychosis was so dominant that it drove her to kill her children in the way she did, her psychosis symptoms would be seen after this, but the hospital notes said otherwise.

"If there were psychotic symptoms there, they would have been there before the alleged offence and they would have been there after."

The defence suggested that Lauren's psychosis could have been masked as she was on anti-psychotic medication in the hospital after the alleged offending but Dr Monasterio said she was on a low dosage, lower than patients diagnosed with psychosis.

Dr Monasterio said he saw no evidence Lauren was so concerned the kids would come to harm that she would kill them to protect them.

"What is not there from what I can determine… is that she is seriously scared that the children will suffer," he said.

Toohey said Lauren did not have that fear until 4:30pm on the day of the killings when she had an encounter with a creepy boy at the park. The family were warned at the park there was a teenage boy taking photos of the children which led her to believe New Zealand wasn't safe.

But Dr Monasterio said if she was experiencing a delusion it would go beyond that thought. She would believe the guy would harm them not could harm them, therefore, the thought was an anxious concern, he said.

He also said psychotic people are definitive with their answers. For example, Lauren said the children in Timaru "seemed sad" - the word "seemed" is more indicative of someone with depression as a person experiencing psychosis would say the children are sad.

However, Toohey said if the killings were not associated with depression and Lauren lost it to anger, it "just doesn't fit" that she would go on to kill all three children.

She also wouldn't continue to tell psychiatrist she had done the right thing by killing her children, Toohey alleged.

Did Lauren have postpartum depression?

Toohey also grilled Dr Monasterio over whether Lauren had postpartum depression. 

Dr Monasterio said Lauren's depression was there before her pregnancy and persisted after she had her children. He said since it was the same depression throughout it was not postpartum depression.

"It occurred well before the defendant's pregnancy… Postpartum means after birth, her depression was already there," Dr Monasterio told the jury on Tuesday.

He also told the court he believed Lauren experienced a full remission of symptoms from November 2020 to June 2021.

Lauren Dickason and her three children.
Lauren Dickason and her three children. Photo credit: File

On Wednesday, Toohey suggested Lauren's depression symptoms had not remitted. She pointed to messages sent around that showed signs she was still suffering.

"You've got to be fair here, doctor, and accept that these messages are painting a real picture of Mrs Dickason's mental health at this time," Toohey said.

Dr Monasterio said the messages were part of a number of sources he weighed up when coming to his conclusion. He accepted there is a mix of information here as Dickason and people around her said her mood had improved.

"The subjective report from the defendant when I interviewed her is that she had achieved an improvement in her mood to the extent that she said she felt the best she had done for 12 years," Dr Monasterio said.

"I do accept it's a tricky balancing act."

The trial continues before Justice Cameron Mander.

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