The History of Parricide: Intentionally Killing a Close Family Member

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Murdering one’s own mother or father is an act so reviled throughout history that no King, Queen, Emperor, Sultan or dictator wanted to acknowledge it even existed by making it a discrete criminal offence. This is despite many such heads of empires and states falling victims to the crime.

And that tradition continues in many nations to this very day.

Parricide was initially defined as the murder of a person’s own mother (matricide) or father (patricide), but the meaning has evolved in many societies to include the intentional killing of any near relative, such as an offspring (filicide), sibling (fractricide), uncle or aunt (avunculicide), niece or nephew (nepoticide) or grandparent who is no longer considered useful to the family (senicide, or geronticide where the person is left to die).

In many countries, the crime of murder encompasses all such acts.

Some countries do, however, have separate offences relating to some types of familial killings.

And there have certainly been many such crimes to shock and appal societies for thousands of years, up until the present day.

Infamous historical cases of parricide

King Sennacherib of Assyria was murdered by his son in the year 681BCE (before the common era), King Bimbisara of Magadha (Modern-Day India), who was a close friend of ‘Buddha’, fell victim to the same crime also at the hands of his son in 493 or 492BCE, and King Sennacherib of was also killed by his son in 495CE (common era).

Roman Emperor, Nero, killed his mother in 59CE, and historians debate whether Julius Caesar was also the victim of parricide on the notorious day of 15 March 44BCE, as Brutus was rumoured to have been his adopted son.

Suspicions regarding the latter were reinforced by the Emperor’s final words to Brutus when being stabbed: ‘Tu quoque mi fili’; translated, meaning ‘You too, my son’

Cleopatra, Queen of Egypt’s daughter, Princess Cleopatra III, is subject to similar historical speculation, that she, too, was murdered by her son, in the year 101BCE.

Whilst these parental killings took place before long ago, the incidence of children killing their parents persists to this very day.

Modern times

In 1955, United Airline Flight 629 was blown up by a bomb planted by Jack Gilbert Graham, murdering 43 passengers, including his mother.

In 1966, a former sniper with the US Marines, Charles Whitman, stabbed his mother and wife to death, before wreaking havoc on the community by murdering 15 people and injuring 31 from a tower at the University of Texas.

In 1986, a former US Vietnam War Veteran killed his mother and 29 mainly restaurant patrons, wounding a dozen more, in Bogota, Colombia.

In 1987, England’s township of Hungerford suffered much grief when 6 townspeople were shot dead by labourer Michael Robert Ryan, who also murdered his mother.

In 2001, Filipino born Australian, Sef Gonzales, murdered both his parents and sister in Sydney, Australia. was subsequently imprisoned for life. Incidentally, the Philippines is a nation which makes parricide a discrete criminal offence. 

And in 2015, the beloved coach of the Adelaide Crows AFL team, Phil Walsh, by the son he loved and cherished, who was found to have been suffering from a mental illness.

Two young murderers of US school massacres were also perpetrators of parricide also.

These are just a few of the thousands of cases of parricide throughout history.

Why do children kill their parents?

Historians report that from around the years 1600 to 1740, parricide was viewed as the most heinous crime imaginable; simply following on with how Ancient History also considered it.

It was regarded as a type of aggravated homicide, with Roman law punishing children convicted of the offence by hanging them in chains.

There is certainly evidence that such crimes have been committed for greed or to obtain a political advantage, such as to usurp their close family members. And there have been those with anti-social or psychopathic tendencies that have perpetrated the offence for self-gratification.

Little or no consideration was given in early times to the fact that many such crimes have resulted from mental health conditions.

However, the National Centre for Biotechnology Information (NCBI), amongst other clinical focused research organisations, endorsed by the National Library of Medicine (NLM), 27 National Institutes of Health (NIH) and the US Department of Health and Human Services (DHHS), found that one of the main causes of parricide in the United States is indeed psychiatric illness.

And there is research to suggest that the objective seriousness of such crimes is often mitigated by exposure to horrendous family violence including sexual violence, which is a continuing problem in Australia as well as elsewhere in the world.

Research into family violence in Australia

There is an enormous amount of research to suggest that violent crimes including homicide offences correspond with exposure to violence at an early age, including domestic and family violence.

To address the issue of family violence, the Council of Australian Governments (COAG) Advisory Panel (whose responsibilities were taken over by Australian National Cabinet in 2020), released recommendations for the 2010 to 2022 National Plan to reduce such violence.

And while it did not specifically address parricide, it had been hoped that the Plan would reduce underlying issues that lead to the commission of this and other violence crimes.

In terms of statistics, the Australian Institute of Criminology’s (AIC) National Homicide Monitoring Program (NHMP) Report, estimated that about 4% of all homicides are by way of parricide.

However, again, the research into parricide and the specific causes thereof is lacking.

In terms of overall homicides, there were 278 homicides in Australia during 2019 / 2020 , of which 81 were domestic violence related. 14 were the result of filicide and 11 were by child on parent / parent on child parricide:

Overall homicides by jurisdiction were as follows:

  • NSW        94
  • VIC           68
  • QLD         53
  • WA          34
  • SA           14
  • ACT            2
  • NT             8
  • TAS            5

Legal implications: the defence of mental illness

Parricide is regarded as a crime that is not only difficult to understand, but equally difficult to both prosecute and defend given assumptions such as a person must be suffering from a severe mental illness to bring themselves to commit it.

Indeed, contravening the historical ‘sanctity and intimacy of a parent to child bond’ in such a decisive and heinous way raises questions about whether the alleged perpetrator was suffering from a mental illness to such an extent that he or she is not legally responsibility for the act.

Commonly referred to as ‘the defence of mental illness’, the legal principle that a person is not guilty if they were of unsound mind at the time of the alleged offending was previously known as ‘the insanity defence’.

In 1843, the British case of R v Daniel M’Naghten enshrined the principle into law, ruling that ‘a defect of reason, from disease of the mind’, to the extent where one does not know what they are doing or does not know what is wrong, is considered a full defence to a crime, including what would otherwise be considered murder.

Fast-forward today, and on 27 March 2021, the law relating to the ‘mental illness defence’ –  contained in the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (the Act) – came into effect in New South Wales.

The Act makes clear that the defence of mental illness – formally known as ‘the defence of mental health impairment or cognitive impairment’ – is a complete defence to criminal charges.

The defence

Section 28 of the Act provides that:

(1) A person is not criminally responsible for an offence if, at the time of carrying out the act constituting the offence, the person had a mental health impairment or a cognitive impairment, or both, that had the effect that the person –

(a) did not know the nature and quality of the act, or

(b) did not know that the act was wrong (that is, the person could not reason with a moderate degree of sense and composure about whether the act, as perceived by reasonable people, was wrong).

It proceeds to state that the question of whether a defendant had a mental health impairment or a cognitive impairment, or both, that had that effect is a question of fact and is to be determined by the jury on the balance of probabilities.

It further states that until the contrary is proved, it is presumed that a defendant did not have a mental health impairment or cognitive impairment, or both, that had that effect.

The law makes clear that an ‘act’ includes an omission as well as a series of acts or omissions.

What is a mental health impairment?

Section 4 of the Act defines mental health impairment as where:

  1. The person has a temporary or ongoing disturbance of thought, mood, volition, perception or memory, 
  2. The disturbance would be regarded as significant for clinical diagnostic purposes,
  3. The disturbance impairs the emotional wellbeing, judgment, or behaviour of the person.

It proceeds to state that a mental health impairment may arise from any of the following disorders but may also arise for other reasons:

  • An anxiety disorder,
  • An affective disorder, including clinical depression and bipolar disorder,
  • A psychotic disorder, and/or 
  • A substance-induced mental disorder that is not temporary.

It makes clear that a person does not have a mental health impairment for the purpose of a determination under the Act if the person’s impairment is caused solely by:

  • The temporary effect of ingesting a substance, or
  • A substance use disorder.

What is a cognitive impairment?

Section 5 of the Act defines cognitive impairment as where:

  • The person has an ongoing impairment in adaptive functioning, 
  • The person has an ongoing impairment in comprehension, reason, judgment, learning or memory, and
  • The impairments result from damage to or dysfunction, developmental delay, or deterioration of the person’s brain or mind that may arise from a condition set out in subsection (2) or for other reasons.

It states that a cognitive impairment may arise from any of the following conditions but may also arise for other reasons:

  • Intellectual disability,
  • Borderline intellectual functioning,
  • Dementia,
  • Acquired brain injury,
  • Drug or alcohol-related brain damage, including foetal alcohol spectrum disorder, or
  • Autism spectrum disorder.

So, what happens if a person is found not guilty due to ‘mental illness’?

An acquittal by reason of mental illness does not mean a person will be released into the community.

Rather, the person will be dealt with under the provisions of the Mental Health Act 2007 (NSW), which may involve involuntary detention in a mental health facility.

The Mental Health Act details the procedures for assessment and review of persons who have been found not guilty by reason of mental health.

So a person who commits a reviled and perhaps incomprehensible act such as parricide as a result of their mental situation, and is subsequently acquitted on that basis, will still be detained with the term of detention initially being indeterminate and subject to rigorous assessment.

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David McCulloch

David McCulloch

David McCulloch has spent years assisting Australian prison inmates and immigration detainees, collaborated with management and academics to establish a Nordic-style recidivism reduction program, written extensively on the history of criminal law and the inequities that plague the criminal justice system and been involved in law-related podcasts and television programs.
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®.

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