An expert claims Lauren Dickason showed no evidence of insanity just after killing her children.

She's on trial at the High Court in Christchurch, accused of murdering her three daughters in Timaru in 2021.

The Crown's first expert, forensic psychiatrist Dr Erik Monasterio, carried out nine hours of interviews with Dickason after the deaths.

The Herald's Anna Leask says Monasterio agrees Dickason was unwell, but claims she doesn't reach the threshold of insanity.

"He said there was no psychosis, there was no cognitive impairment and there were no delusions."

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