The Law, Penalties and Defences for Manslaughter in New South Wales

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Manslaughter, gavel, and handcuffs

Jessica Camilleri was found not guilty of murder by a jury last year, but found guilty instead of the lesser charge of manslaughter, after her lawyers argued she was impaired by a mix of mental disorders including autism spectrum disorder, an intellectual disability and intermittent explosive disorder with a history of violent outbursts.

During the jury trial, the court heard that Ms Camilleri had a fascination with violent horror movies, and that she attacked her mother with seven kitchen knives, four of which broke during the attack.

Ms Camilleri stabbed her mother more than 100 times in the neck and head, before decapitating her and cutting out her eyeballs, tongue and nose.

Ms Camilleri told police she then took her mother’s severed head “in a fit of rage, of panic”, and attempted to show it to her neighbour “for evidence” – but it slipped from her hands and landed on the footpath outside the home, where it was discovered by first responders.

The “most serious example of manslaughter a court could consider”

Presiding Justice Helen Wilson said the unlawful killing of Rita Camilleri at her St Clair home in 2019 was “the most serious example of manslaughter a court could consider”.

In handing down her sentence, her Honour said it was “a crime of extraordinary viciousness and brutality,” although she also accepted the crime was “entirely spontaneous” and predicated by Camilleri’s fear of being returned to a mental institution.

The court originally heard that In the lead up to the killing there had been some stressful events and tension within the family home and, and Ms Camillieri had stopped taking medication, and was trying natural alternatives.

Jessica Camilleri was cared for solely by her mother Rita. Rita’s sister told the court that Rita’s love and care for her daughter was ‘remarkable’ but it blinded her and despite Jessica’s violent outbursts and interest in violent films, her mother never thought she would hurt anyone.

Ms Camilleri was sentenced to a maximum 21 years and seven months, with a non-parole period of 16 years and two months.

Manslaughter in NSW

Section 18 of the Crimes Act 1900 (NSW) (“the Act”) defines murder as any act or omission with “reckless indifference to human life” or “intent to kill or inflict grievous bodily harm on another person” which causes death.

Subsection 18(1)(b) of the Act provides that “[e]very other punishable homicide shall be taken to be manslaughter.” The offence does not require the prosecution to prove reckless indifference to life or an intent to kill or cause grievous bodily harm.

Section 24 of the Act prescribes a maximum penalty of 25 years’ imprisonment for the offence.

There are at three broad categories of manslaughter in NSW:

  1. Manslaughter by unlawful and dangerous act,
  2. Manslaughter by criminal negligence, and
  3. Manslaughter by excessive self-defence.

Manslaughter by unlawful and dangerous act

This is a form of involuntary manslaughter which requires the prosecution to prove beyond reasonable doubt that:

  1. the defendant killed another person,
  2. the death was caused by an act of the defendant,
  3. the defendant intended to commit the act that caused the death,
  4. the act was unlawful, and
  5. the act was dangerous.

The alleged ‘dangerous and unlawful act’ must be one that a reasonable person in the position of the defendant would have appreciated as exposing another or others to the risk of serious injury; Wilson v The Queen (1992) 174 CLR 313.

Manslaughter by criminal negligence

This is another form of involuntary manslaughter. To establish the offence, the prosecution must prove that:

  1. the defendant owed a legal duty of care to the deceased,
  2. the defendant committed an act or omitted to do an act,
  3. the act or omission substantially caused or accelerated the death of the deceased,
  4. the act or omission breached the duty of care owed to the deceased, and
  5. the act or omission amounted to criminal negligence and deserved criminal punishment for the offence of manslaughter because:
  • it fell far short of the standard of care which a reasonable person would have exercised in the circumstances; and
  • involved such a high risk that death or really serious bodily harm would follow as a result of it.

In Lavender v The Queen (2005) 222 CLR 67, the High Court found that the degree of negligence must be at least as high as recklessness.

Australian courts have been loath to impose positive obligations on individuals when it comes to assisting others. However, the courts have found that liability for manslaughter may arise in the following situations.

  • where the defendant had a legal obligation to care for the deceased – eg was a parent or carer – and failed to do so; Russell[1933] VLR 59.
  • where the defendant assumed a duty of care towards a helpless person and secluded them so as to prevent others from rendering assistance; Stone and Dobinson [1977] 1 QB 354, Taktak (1988) 14 NSWLR 226.

Manslaughter by excessive self-defence

Section 421 of the Act provides that a person is guilty of manslaughter rather than murder where he or she:

  • uses force that involves the infliction of death, and
  • the conduct is not a reasonable response in the circumstances as he or she perceives them, but the person believes the conduct is necessary:
  • to defend themselves or another person, or
  • to prevent or terminate the unlawful deprivation of his or her liberty or the liberty of another

The laws of manslaughter are often seen as a net which captures those whose dangerous acts or omissions cause the death of others, despite a lack of evidence proving an intention to kill or cause serious harm.

Self-defence is the main defence to manslaughter in our state.

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Ugur Nedim

Ugur Nedim

Ugur Nedim is an Accredited Criminal Law Specialist with 25 years of experience as a Criminal Defence Lawyer. He is the Principal of Sydney Criminal Lawyers®.

Sonia Hickey

Sonia Hickey is a freelance writer, magazine journalist, and owner of 'Woman with Words'. She has a strong interest in social justice and is a member of the Sydney Criminal Lawyers® content team. Sonia is the winner of the Mondaq Thought Leadership Awards, Spring 2022.

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