The NSW Supreme Court has found a Blue Mountains woman not criminally responsible for the deaths of her two sons, aged nine and 11. The boys were stabbed in the family home in September 2024 and were later found by their father, who called emergency services.

Justice Richard Cavanagh said the woman had entered pleas of not guilty to murder on the basis of mental health impairment. He entered a special verdict of “act proven but not criminally responsible”, meaning the court accepted that she carried out the acts but found she was not criminally responsible for them.

According to ABC News Australia, the court heard evidence from three psychiatric doctors who interviewed the woman several times by audio-visual link. Justice Cavanagh said their evidence showed a “degree of similarity, if not unanimity” in their assessments.

The psychiatrists concluded that, at the time of the killings, the woman was suffering from severe major depression that had made her thought processes psychotic. They also considered that she was experiencing nihilistic thinking and was unable to reason beyond a belief that her children would be better off dead in a bad world.

Justice Cavanagh said the expert evidence overwhelmingly indicated that the woman did not know her actions were wrong, although she understood the nature and quality of what she was doing. He said the court relied on psychiatric opinion in reaching that conclusion, while the legal determination remained a matter for the court.

The woman appeared by audio-visual link during the judgment, sitting with her head lowered and wiping her eyes at times. She will be detained at a location selected by the Mental Health Review Tribunal, which will supervise her and ensure she receives care and treatment. Justice Cavanagh said she could not be released unless the tribunal was satisfied that her release would not seriously endanger her or members of the public, and described the case as particularly tragic.