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Supreme Court 18 December 2020

R v Krey (No 3)

[2020] NSWSC 1811

Homicide
CRIMINAL LAW TRIAL BY JUDGE ALONE SINGLE COUNT OF MURDER ELEMENTS OF MURDER ESTABLISHED S 23A OF THE CRIMES ACT 1900 (NSW) ACCUSED FOUND GUILTY OF MANSLAUGHTER

Citation: R v Krey (No 3) [2020] NSWSC 1811
Court: Supreme Court of New South Wales
Date: 18 December 2020
Judge: Ierace J

Background

The accused was charged with the murder of a 55-year-old man at Whalan on 15 July 2017. The accused was 19 years old at the time. The killing, by multiple stab wounds to the upper body, was witnessed by several people and was not in dispute.

The accused had a significant history of mental health and neurodevelopmental conditions, including complex Post-Traumatic Stress Disorder (PTSD), Foetal Alcohol Spectrum Disorder (FASD), and intermittent explosive disorder. He had been on medication for much of his childhood and adolescence, but had ceased taking it after moving back to live with his mother in the weeks before the incident. His capacity for self-control had markedly deteriorated in that period.

On the day of the stabbing, the accused awoke in an angry mood and became involved in an aggressive argument with his mother. The deceased, a neighbour who intervened to assist, was fatally stabbed. The sole issue at trial was the accused's state of mind at the time of the killing, specifically whether the partial defence of substantial impairment applied to reduce the verdict from murder to manslaughter.

  • Whether the elements of murder under s 18(1)(a) of the Crimes Act 1900 (NSW) were established beyond reasonable doubt.
  • Whether the accused had established, on the balance of probabilities, the partial defence of substantial impairment under s 23A of the Crimes Act 1900 (NSW).
  • Whether the accused's capacity to control himself was substantially impaired by an abnormality of mind arising from an underlying condition at the time of the killing.
  • Whether that impairment was so substantial as to warrant reducing liability from murder to manslaughter under s 23A(1)(b).

Decision

Ierace J, sitting without a jury, was satisfied beyond reasonable doubt that the elements of murder were established. The accused had killed the deceased, and the act was done with the requisite mental state. The onus then shifted to the accused to establish the partial defence of substantial impairment on the balance of probabilities.

The court heard from four forensic experts: two retained by the defence (psychiatrist Dr Olav Nielssen and neuropsychologist Dr Molly Schafer) and two by the Crown (psychiatrist Dr Stephen Allnutt and neuropsychologist Dr Susan Pulman). Their evidence addressed the accused's complex PTSD, FASD, and intermittent explosive disorder, all of which constituted pre-existing conditions within the meaning of "underlying condition" in s 23A(8).

The court accepted that the accused's capacity to control himself had deteriorated significantly in the weeks before the stabbing. Relevant factors included his ceasing to take medication after moving back to live with his mother, the absence of the stabilising supervision he had previously received, a documented episode shortly before the killing in which he held a knife to his own throat in frustration, and a long history from early childhood of violent behaviour associated with knives when in his mother's care. These findings supported the conclusion that his self-control was substantially impaired by an abnormality of mind on the day of the killing.

Weighing all the factors bearing on s 23A(1)(b), Ierace J was satisfied on the balance of probabilities that the impairment was so substantial that liability for murder should be reduced to manslaughter. The accused was found not guilty of murder but guilty of manslaughter.

Orders Made

• The accused is found not guilty of murder but guilty of manslaughter.

Key Takeaways

  • Under s 23A of the Crimes Act 1900 (NSW), a partial defence of substantial impairment requires the accused to prove on the balance of probabilities that, at the time of the killing, their capacity to understand events, judge right from wrong, or control themselves was substantially impaired by an abnormality of mind arising from a pre-existing condition of a non-transitory kind.

  • Complex PTSD, FASD, and intermittent explosive disorder can each constitute an "underlying condition" for the purposes of s 23A, providing the evidentiary foundation for a substantial impairment defence.

  • Deterioration in an accused's condition in the period leading up to a killing is relevant to the s 23A inquiry. Here, cessation of medication, removal of external supervision, and documented episodes of loss of control in the weeks before the incident supported the finding of substantial impairment.

  • The Supreme Court confirmed that the two-stage inquiry under s 23A first requires satisfaction of the impairment threshold under s 23A(1)(a), and then a separate normative judgment under s 23A(1)(b) as to whether the impairment was so substantial as to warrant reduction of the offence to manslaughter. Expert opinion on the second question is not admissible (s 23A(2)), leaving that determination entirely to the court.

  • A finding of substantial impairment does not result in acquittal. The accused in this case was convicted of manslaughter, not murder, pursuant to s 23A(5).

Legislation and Cases Referenced

Legislation
- Crimes Act 1900 (NSW), ss 18, 23A
- Criminal Procedure Act 1986 (NSW), ss 133, 151
- Evidence Act 1995 (NSW), s 165
- Mental Health (Forensic Provisions) Act 1990 (NSW)

Cases
- Quinn v R [2018] NSWCCA 297
- R v Billy Krey (No 2) [2020] NSWSC 199
- R v Billy Krey [2019] NSWSC 762
- R v Byrne [1960] 2 QB 396