Manslaughter
Understanding Manslaughter Charges in Australia
Manslaughter is a serious offence under section 18(1)(b) of the Crimes Act 1900 (NSW) but is considered less morally culpable than murder due to the absence of deliberate intent to kill. It generally applies when a person causes the death of another through criminal negligence, an unlawful and dangerous act, excessive self-defence, or a failure to act.
- Manslaughter is governed under section 18 of the Crimes Act 1900 (NSW) and similar provisions in other states and territories, including the Criminal Code 2002 (ACT).
- The offence is used where death is caused unintentionally or in circumstances where murder cannot be proven beyond reasonable doubt.
- While the maximum penalty is severe (up to 25 years imprisonment), sentences can vary significantly depending on the facts.
If you are charged with manslaughter, contact Brightstone Defence Criminal Lawyers for experienced and strategic legal representation.
Manslaughter is defined as unlawful killing without the intent to kill or cause grievous bodily harm. In New South Wales, it is dealt with under section 18 of the Crimes Act 1900 (NSW), and in the ACT under section 15 of the Criminal Code 2002. The offence differs from murder because it does not require the prosecution to prove that the accused intended to kill the victim.
There are four main categories of manslaughter:
- Criminal negligence
- Unlawful and dangerous acts
- Excessive self-defence
- Omissions (failing to act when a duty of care exists)
Manslaughter is subsequently broadly categorised into two types:
1. Voluntary Manslaughter
Occurs when a person intends to kill or cause serious harm but has a partial defence to murder such as provocation, substantial impairment due to mental health, or excessive self-defence. These defence reduce what would otherwise be murder to manslaughter.
2. Involuntary Manslaughter
Occurs when a person does not intend to kill, but their actions are so careless, unlawful, or dangerous that they result in another person’s death. This includes:
- Manslaughter by criminal negligence – such as failing to provide medical care to a dependent
- Manslaughter by unlawful and dangerous act – such as a violent assault that unintentionally causes fatal injuries
Elements the Prosecution Must Prove
To secure a conviction for manslaughter, the prosecution must prove, beyond reasonable doubt, at least one of the following:
1. Criminal Negligence
- The accused owed the deceased a legal duty of care.
- The accused breached that duty through conduct that fell far below the standard expected of a reasonable person.
- The breach of duty caused the death of the victim.
- The negligence was so gross as to warrant criminal punishment.
2. Unlawful and Dangerous Act
- The accused committed an act that was both unlawful and dangerous.
- A reasonable person in the same position would have recognised the act posed a serious risk of harm.
- The act directly caused the victim’s death.
3. Excessive Self-Defence
- The accused believed they were acting in self-defence but used more force than was reasonably necessary in the circumstances.
- The force used was disproportionate, resulting in death.
4. Omission to Act (Duty of Care)
- The accused had a legal duty to act (e.g. parent to child, caregiver to vulnerable adult).
- They failed to act in a way a reasonable person would.
- The failure to act caused the death.
Possible Defences
A skilled criminal defence lawyer may raise one or more of the following defence, depending on the facts of your case:
- Self-defence (if it can be proven that the use of force was reasonable)
- Duress (if you were forced to act under threat)
- Necessity (if you acted to prevent a greater harm)
- Automatism (if the act was involuntary due to a medical or mental condition)
- Mental illness (under the Mental Health Act)
Each defence requires specific legal arguments and may lead to an acquittal or reduction in charges.
Potential Penalties
Manslaughter carries serious penalties across Australia.
- The maximum penalty is 25 years imprisonment in NSW and the ACT.
- However, average sentences vary and are significantly influenced by the circumstances of the offence.
- In many cases, manslaughter convictions result in prison terms of 5 to 10 years, with an average non-parole period of around 4.5 years.
Sentencing factors include the nature of the act, level of negligence or recklessness, remorse shown, and any prior criminal history.
Legal Process
& Options
Manslaughter is a highly complex area of criminal law involving nuanced legal definitions, forensic evidence, and subjective assessments of intent, negligence, and causation. If you are facing a manslaughter charge, you should seek immediate advice from an experienced criminal defence lawyer. The outcome of your case may depend on technical legal arguments and thorough case preparation.
Pleading
Not Guilty
If you plead not guilty, Brightstone Defence will carefully assess the circumstances and build a strong defence strategy. This may involve:
- Arguing lack of intent or foresight required to prove manslaughter
- Challenging the prosecution’s version of events
- Presenting expert evidence to support your defence
- Identifying weaknesses or inconsistencies in the prosecution’s case
Our experienced criminal lawyers will represent you through every stage, from case preparation to trial, ensuring that your rights are protected and that the best possible outcome is pursued.
Pleading
Guilty
If you choose to plead guilty to manslaughter, your matter will proceed directly to sentencing. An early guilty plea may:
- Demonstrate remorse and take responsibility for your actions
- Reduce the severity of the sentence imposed by the court
- Help avoid a lengthy and complex trial
However, manslaughter is a serious offence that carries significant penalties, including lengthy imprisonment. You should obtain legal advice before deciding how to plead, to fully understand the consequences and available options.
- Murder involves intentional or reckless killing
- Manslaughter involves a lack of intent, but death occurs due to:
- Criminal negligence
- Unlawful and dangerous acts
- Excessive self-defence or provocation
It means the person knew their actions were likely to cause death, but continued anyway.
For example, setting fire to an occupied house or hitting someone violently knowing it could be fatal.
Life imprisonment means a person can be kept in prison for the rest of their natural life, though courts may set a non-parole period (minimum time before eligibility for release).
In rare or extreme cases, the court may impose a “life means life” sentence with no parole.
- Yes, if they:
- Encouraged, directed, or helped the killer (accessory or joint criminal enterprise)
- Participated in a crime that led to a foreseeable killing
- Ordered or planned the killing
This applies when someone causes a death while committing a serious crime (e.g., robbery, assault, arson), even if there was no intent to kill.
It’s treated as murder due to the dangerous context.
- Yes, if a person:
- Genuinely believed they needed to defend themselves or another person, and
- The force used was reasonable
If the self-defence was excessive, it may reduce murder to manslaughter.
Families can access:
- NSW Victims Services (or state equivalent)
- Funeral and counselling support
- Victim impact statements during sentencing
- Access to information through Corrective Services
A jury of 12 people decides whether the accused is guilty or not guilty based on the evidence presented in court.
The judge oversees the trial and imposes the sentence if there is a conviction.
- Yes
Facing a murder charge is extremely serious and requires immediate legal representation. An experienced criminal defence lawyer can protect your rights, review evidence, and develop a strong defence strategy tailored to your case.
At Brightstone Defence, our expert criminal lawyers provide strategic guidance through every stage of the legal process. We assess the circumstances, identify possible defences, and work to achieve the best possible outcome. Contact us today for confidential advice and professional representation.
- Murder involves intent to kill or cause serious injury.
- Manslaughter involves:
- No intent, but still unlawful actions or negligence leading to death.
- It is considered less morally blameworthy than murder.
There are two main types under Australian law:
- Voluntary manslaughter – where there is intent, but the offence is downgraded from murder due to mitigating circumstances (e.g. provocation or excessive self-defence).
- Involuntary manslaughter – where the death was caused by:
- An unlawful and dangerous act, or
- Gross negligence (e.g. a duty of care was breached with serious consequences).
- This occurs when a person:
- Commits an illegal act, and
- That act is dangerous, and
- It causes someone’s death (even if death was not intended).
- This applies when someone owes a duty of care (e.g. a parent, carer, or professional), and:
- Fails to take reasonable steps to protect a person, and
- That failure results in death.
- Yes. For example:
- A DV-related assault that unintentionally causes death (e.g. head injury from a shove)
- Failing to seek medical help for a partner after a violent incident
- Extreme neglect or abuse that leads to a partner or child’s death
These cases may be charged as manslaughter instead of murder depending on intent and circumstances.
- Yes, in some cases. For example:
- If a person owed a duty of care and their failure caused death (e.g. neglect, omission)
- If they were involved in an unlawful act that caused someone else to die, even if unintentionally
- Yes
If a person acted to protect themselves or others, and used reasonable force, it may be a full defence to the charge.
However, excessive self-defence may reduce a murder charge to manslaughter.
- Yes
Prosecutors or a jury may decide the evidence does not support intent required for murder, and instead proceed with or return a manslaughter conviction.
This can happen during plea negotiations or trial.
- Murder involves intent to kill or cause serious injury.
- Manslaughter involves:
- No intent, but still unlawful actions or negligence leading to death.
- It is considered less morally blameworthy than murder.
There are two main types under Australian law:
- Voluntary manslaughter – where there is intent, but the offence is downgraded from murder due to mitigating circumstances (e.g. provocation or excessive self-defence).
- Involuntary manslaughter – where the death was caused by:
- An unlawful and dangerous act, or
- Gross negligence (e.g. a duty of care was breached with serious consequences).
- This occurs when a person:
- Commits an illegal act, and
- That act is dangerous, and
- It causes someone’s death (even if death was not intended).
- This applies when someone owes a duty of care (e.g. a parent, carer, or professional), and:
- Fails to take reasonable steps to protect a person, and
- That failure results in death.
- Yes. For example:
- A DV-related assault that unintentionally causes death (e.g. head injury from a shove)
- Failing to seek medical help for a partner after a violent incident
- Extreme neglect or abuse that leads to a partner or child’s death
These cases may be charged as manslaughter instead of murder depending on intent and circumstances.
- Yes, in some cases. For example:
- If a person owed a duty of care and their failure caused death (e.g. neglect, omission)
- If they were involved in an unlawful act that caused someone else to die, even if unintentionally
- Yes
If a person acted to protect themselves or others, and used reasonable force, it may be a full defence to the charge.
However, excessive self-defence may reduce a murder charge to manslaughter.
- Yes
Prosecutors or a jury may decide the evidence does not support intent required for murder, and instead proceed with or return a manslaughter conviction.
This can happen during plea negotiations or trial.
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