This table is intended to be used as a guide only. Individual cases should be read if they are to be relied upon.
Section 23A was amended on 3.4.1998 to replace Diminished Responsibility with
Substantial Impairment. The amended section applies to alleged offences
committed after the date of the amendment.
 NSWSC 944
Assault - domestic
Mother smothered 3y daughter - father of child taking Family Court action to gain custody.
Violent upbringing - history of sexual abuse
 NSWSC 1146
Stabbing - domestic
MT 3y 6m
AT 2y 6m
Stabbed mother in law with scissors - wife stabbed in shoulder attempting to help - estrangement from wife caused primarily by V - had gone to house of wife to see her resulting in confrontation with V.
Excellent prospects of rehabilitation
 NSWSC 447
Assault – domestic
Female strangled husband and poisoned 1y daughter. Attempting to kill self when found by police. Accidentally killed husband trying to keep him from preventing her killing herself and daughter.
Daughter suffering from cerebral palsy and worried no one would look after her.
 NSWSC 525
Stabbed wife with kitchen knife - found by police threatening to jump off 12 storey roof - undiagnosed Huntington's Chorea disease caused V to become irrationally abusive to offender over long period of time.
Forgiven by 3 children and low risk of re-offending.
 NSWSC 648
Female removed 1y son from adoptive parents during access visit, - stabbed him and hid body in dam - impulsive killing.
Forced into adoption by family. Support of family; remorse; rehabilitation.
 NSWSC 867
Male killed wife of 51y bashing her to death with hammer while asleep. Both husband and wife ill, and he suffered major depression after house damaged by hailstones.
Deep remorse. Condition of bond to continue with treatment program.
 NSWSC 1088
Killed young child intending to then kill self.
Remorse and retained family support.
 NSWSC 420
Strangled wife of nearly 50 years to death.
Offence completely out of character - excellent personal and family history - remorse - voluntarily surrendered to police - considered suicide but concerned about effect on daughter.
 NSWSC 787
NPP 4y 6m
Stabbed wife after forming unfounded suspicion that she was unfaithful to him. Suffering delusional disorder focussed upon perceived unfaithfulness of wife. Had similar obsession with former wife. Also intoxicated at time of offence.
Remorse - 25% discount for plea.
 NSWSC 650
Stabbed female sharing house with after V argued and abused other occupants of house for several hours. Provocation assessed against background of stressful and exploitative environment of house. Offence uncharacteristic. Degree of provocation high - accepted provocation was relevant to culpability.
Unhappy childhood in West Timor - Miserable existence in Australia - Genuine remorse - Suffering psychiatric illness at time of offence - Isolation in gaol.
 NSWSC 685
Struck V with a hammer several times during altercation in boarding house room.
 NSWSC 753
VG – murder trial
(20% for offer)
NPP 3y 9m
 NSWSC 923
Stabbing - general
NPP 5y 3m
 NSWSC 1082
(just under 10%)
Hung de facto wife's five year old daughter in noose from pergola following separation from de facto.
Sexually assaulted as child.
 NSWSC 150
Major depressive illness
Stabbed estranged wife's lover in their bed - provocation fell short of legal provocation but combined with SI to reduce sentence - spontaneous.
Devastated by marriage breakdown - Considerations of deterrence and retribution much reduced - Remorse - Good prospects of rehabilitation
 NSWSC 415
2 x Att murder
FT 15m 10d
Suffering delusional disorder focussed on perceived sexual abuse by fathers of children - Faced losing custody of children at Family Court hearing - Attempted to kill self and three children by carbon monoxide poisoning - Only baby died
Improvement in mental health - Protective custody - Remorse
 NSWSC 502
NPP 3y 6m
Female - Stabbed step-brother in neck after being called a dog - Prior de facto relationship with victim characterised by violence - Suffering paranoid delusions since birth of youngest son and schizophrenic illness at time of offence
Improvement in mental condition - Chaotic life including drug addiction, turbulent relationships and prostitution
 NSWSC 1068
Shooting - general
While on a shooting excursion shot good friend under delusional belief he had raped A's mother, sister and grandmother. Tried to get V's father, who was present, to say V had shot himself.
 NSWCCA 363
Mother suffocated 10y autistic son – Suffering major depressive illness – Unable to obtain proper assistance or intervention – V very difficult to manage – Verbal and physical abuse by husband – Illness and death of family members – Step father physically abusing daughter – Made serious attempt at suicide
Remorse and contrition – Evidence of rehabilitation with daughter
 NSWSC 547
 NSWSC 549
Shooting - domestic
Possess unathor firearm
Deliberate and premeditated killing of mother's de facto husband – angered by perception that V stealing from business and assaulting mother – genuine attempt to commit suicide
Suffering depression – serious injuries from suicide attempt – Remorse – Good character
 NSWSC 675
 NSWCCA 452
Assault - general
(murder trial – 20% for offer))
Assaulted drug supplier with cricket bat - psychotic episode caused by amphetamine use – dismembered body and buried in backyard
Diabetic - long term drug abuse
 NSWSC 1030
 NSWSC 1298
Sentence initially deferred 12m
NPP 2y 9m 14d
Killed wife – awoke during night and struck V with glass ornament – placed sufficient pressure on throat to break bone – doused V with accelerant and set fire to unit – probably cause of death suffocation or asphyxiation – V died before burned by fire
Argentinean – separated from wife but on good terms – attempted suicide after lighting fire
 NSWSC 1344
McClellan CJ at CL
Female shot female cousin in head – upset by victim's plan to move out of shared accommodation – possessed gun with intention of committing suicide – impulsive offence - suffering major depressive disorder
Remorse – Chinese national with language difficulties
 NSWSC 21
NPP 1y 3m 2d
Mother drowned 5m daughter in river – Suffering psychotic illness (substantial impairment in upper range)
Protective custody – Family and community support – Remorse – Good prospects of rehabilitation
 NSWSC 486
Female - Took knife to hotel and stabbed estranged de facto husband – Responding to daughter's allegation that V sexually assaulted her – V previously accepted possibility he had sexually assaulted daughter on earlier occasion while drunk – Provocation could be taken into account under s.21A(3) – not sufficient to come under s.23
Offender sexually abused by family members during childhood – Stress disorder – Immediate remorse – Mother to two daughters – Good character
 NSWSC 1199
 NSWCCA 226
(25% for plea and disclosure)
Prisoner kicked and punched to death cellmate in locked cell – suffering chronic psychotic disorder – unable to control urges – criminality of reasonably high order
Also sentenced for bank robbery – armed with shortened firearm – voluntary disclosure of unknown guilt
 NSWSC 295
Parents killed severely disabled 29y son – V suffering blindness, severe mental retardation and restriction of hearing –required surgery to stop brain infection – surgery would cause temporary deafness and reduced quality of life – V difficulty in dealing with changes in life – spontaneous decision brought out of love for son – both offenders suffering major depressive illness brought on by years of stress and commitment to son – mother administered sedative – father killed V – cause of death undisclosed - Severe depressive disorder
Suicide risk – should not be separated
 NSWSC 809
Mother killed 9m daughter – shook baby and head struck against brick fireplace – unable to settle crying child – intent to do GBH – suffering depressive illness and possible other mental conditions exacerbated by cannabis use
Remorse – prior good character
 NSWSC 1047
 NSWSC 1473
Suffering PTSD from war service in Vietnam and brain damage – V seriously mentally unwell, delusional and dangerous - threatening and abusing offender's family – coincidental meeting resulted in offender shooting V multiple times – offender's mental condition affected perception of events and ability to control actions
 NSWSC 622
NPP 5y 6m
 NSWSC 761
Substantial impairment / provocation
Female entered sexual relationship with 22y male – unhappy relationship involving physical abuse, drug abuse and threats to kill – stabbed V during argument – impulsive and sudden offence – element of provocation
Also suffering amphetamine abuse disorder – sexually abused as a child – remorse – prior good character
 NSWSC 1204
Mother received prank calls alleging to be from boyfriend suggesting he had infected her with HIV – confronted and argued with boyfriend – stabbed boyfriend multiple times – acting under delusional belief he would be assaulted by V's associates – previously assaulted by V in home invasion – impaired capacity to judge right from wrong – impaired capacity to control actions
Chaotic and dysfunctional family life
 NSWSC 348
Fatal assault of mother at home – circumstances and motive unknown – Some history of violence against mother when angry or intoxicated – Mother primary carer of offender after car accident caused major brain damage
Remorse limited by mental capacity – difficulty in prison – continued danger to community
 NSWSC 346
Shot V - V made threats he would harm A's family if A did not assist with V's drug cultivation - immediate surrender and confession to police - A and V knew each other from school days - V well-known as aggressive and intimidating – Continuous intimidation from V - A began to abuse drugs and suffer from depressive disorder - A's impairment at high end of spectrum – strong connection between A's depressed mental state and intimidation from V.
Serbian background – wartime memories – no likelihood of reoffending or dangerousness – prior good character – trusted and loyal employee - remorse
 NSWSC 369
NPP 4y 3m
 NSWSC 532
NPP 2y 6m
Frenzied stabbing of 67y wife during argument over breakdown in relationship
History of verbal and physical abuse
 NSWSC 722
(12m FT – cumulative)
Stabbed de facto partner and slit throat – took ice the night before
Drug addiction – not taking medication prior to offence – some insight
 NSWSC 809
Stabbed male acquaintance in block of residential units during struggle – high level of violence
Long history of schizophrenia – cannabis and alcohol use
 NSWSC 956
(murder trial – offered to plead)
Female – With 14y son struck sleeping father of son with tomahawk – son armed with knife – offence planned over extended period - Impairment of self control only – son mentally ill – obsessed with keeping father from normal relationship with son
Good prospects of rehabilitation
 NSWSC 1120
2 x mansl
Vietnamese mother killed 5y son and 3y daughter – attempted to kill children with rat poison – suffocated both children then took poison herself – made several unsuccessful attempted at suicide - distressed at husband's infidelity and leaving relationship – severe depression – killings had an element of retribution although primarily altruistic
 NSWSC 364
Substantial impairment / excessive self defence
(murder trial – some discount for offer)
Assaulted male acquaintance with baseball bat after V had forced entry into house – both intoxicated having been drinking together earlier – V had been loudly and abusively seeking entry to unit – weakened arm and frontal lobe damage influenced perception of threat – mental functioning so affected as to constitute substantial impairment of the mind - brain damage
Offered to plead guilty to manslaughter – mental health and drug problems
 NSWSC 593
Female stabbed 18y sister to death – difficult relationship characterised at times by physical fighting – purchased a knife prior to killing – stabbed sister in neck as she emerged from bathroom
Medication caused obesity affecting self esteem and resulting in poor compliance with medication regime – mood disorder associated with non-compliance with medication prescribed for congenital adrenal hyperplasia
Prior good character - remorse
 NSWSC 670
(murder trial – 25% for offer)
Strangled mother with extension cord - separated from wife and children – V loaned money to A to assist with keeping his home for children – A's home transferred into V's name – relationship between V and A deteriorated – V suffering from early dementia – A suggested they move into separate premises – V responded by saying A and his children could "get out of her house" – A attacked V – brutal killing – approaches worst category but not in worst category.
Major depressive illness from marriage breakdown and access to children – good character – good rehabilitation prospects – remorse.
 NSWSC 339
Assisted V (partner) to commit suicide - ingestion of amitriptyline tablets and final act of suffocation - long relationship of 22 years – V had suffered pain from spinal condition - V expressed wish to die in suicide note – A's participation would not have been discovered but for A's disclosures to police.
Only motive was to assist V in carrying out her express intention - no lengthy period of planning or premeditation - culpability at low end of range of sentences for manslaughter - leniency due to disclosures, confession of guilt and plea of guilty
 NSWSC 614
Suffering from schizoaffective disorder – drowned 2y daughter in canal – had been seeking to kill herself as well – impairment of very high order
Good family support – good prospects of rehabilitation
 NSWSC 1376
RS Hulme J
Stabbing – general
Walked 3km to V's house and stabbed him in chest when he answered the door – attempted to cover scene by setting fire to house
Extremely disturbed youth with significant behavioural problems
Difficult background – suffered some physical and emotional abuse –– suicide attempts – cannabis use – suffered some sexual abuse at hands of V over several years – angered at dissension in family home – facilitated administration of justice in conduct of trial – reasonable prospects of rehabilitation
 NSWSC 922
NPP 3y 2m
Female – drowned 17 month old daughter by leaving in bath – in ongoing destructive cruel relationship with father of child – lack of support - depression and depersonalisation led to actions which couldn't properly assess and control - otherwise a loving exemplary mother.
Good prospects rehabilitation – offer to plead guilty considered as mitigating factor
 NSWSC 1000
 NSWSC 1549
 NSWCCA 70
V and offender shared offender's housing commission house – prolonged physical argument where police called on numerous occasions and AVO taken out on behalf of offender – police declined to remove V from house – offender stabbed V in heart
Lengthy history of mental illness - alcohol, persecutory beliefs concerning the actions of the victim, and untreated schizophrenia
 NSWSC 218
Stabbing - Domestic
Female – staying at home of male acquaintance after time in psychiatric unit – responded to perceived threat by victim that he would rape or murder her – grabbed knife in house and stabbed victim several times – body not discovered for several months – victim had brain damage causing sexual and violent inhibition – element of provocation
History of mental illness – suffering psychosis – significant reduction in moral culpability – remorse – disrupted and abusive childhood including sexual abuse leading to early drug abuse
 NSWSC 1029
 NSWSC 1261
 NSWCCA 229
Stabbing – domestic
(murder trial - 20% for offer)
NPP 5y 1m
(discount for offer to plead increased on appeal to 25%)
Attacked stepfather (V) – V abusive towards A (provocation) – A also concerned about V's inappropriate sexual behaviour towards A's sister – stabbed V and hit over head with hammer.
Provocation by V– remorse – unplanned offence.
Schizophrenia – low risk of re-offending.
 NSWCCA 249
2 x animal cruelty
Assaulted mother and stabbed her twice during argument – killed two cats by slashing throats
 NSWSC 1808
Stabbing - General
Use off weapon to prevent apprehend
NPP 6y 6m
NPP 7y 6m
Female lived with 19y son on rural property - Relationship with neighbour became antagonistic – son fired crossbow at workers on neighbour's property – siege developed with police – attacked police with knife and sledgehammer – police officer fatally stabbed by son – mother aware of possibility of infliction of GBH – mother was dominant offender
Son pleaded guilty to murder
Mother suffered serious mental illness causing paranoia and social isolation
 NSWSC 813
(murder trial - 25% for offer to plea)
Female stabbed partner once in back – circumstances unclear – victim intoxicated and self-harming - below mid-range
Aboriginal with deprived and dysfunctional childhood – involved in abusive relationships – profound remorse
 NSWSC 1155
(murder trial - 33% plea and assist)
Female arranged killing of partner by male lover – fed victim sleeping tablets then called co-offender to house – victim killed in unknown manner and body disposed of by co-offender – violent relationship with Victim – barely sufficient level of substantial impairment – aggravating factors: stupefying drug – in company – in victim's home – planned
Gave evidence against co-offender – remorse- mother to five children
Co-offender Roff sentenced for murder
 NSWSC 1317
Stabbed V female partner – A reacted to V making an arrangement of fake marriage between herself and her nephew so that he could live in Australia – A did not agree to the fake marriage as he was her husband and would have to make a false declaration – abandonment - stabbed V eight times.
Underlying condition of severe, post-traumatic stress disorder, depression and cognitive impairment as survivor of torture while political prisoner in Ethiopia and trauma in refugee camps.
Prior good character.
Hart (No. 5)
 NSWSC 1612
Shooting - General
7 further offences dealt with under s 168 CPA
NPP 5y 4m
NPP 5y 8m
Shot male V in head with pen gun – argument over drugs – both A and V worked together as drug dealers –both addicted to drug Ice.
Impulsive, spontaneous act - no planning or premeditation– offence arose out of A being substantially impaired by abnormality of mind arising from a stimulant use disorder or a substance induced psychotic disorder.
Strong subjective case - very good prospects of rehabilitation - low risk of further offending – special circumstances.
 NSWCCA 277
Stabbing – Domestic
NPP 4y 9m
Father stabbed 29y daughter in back during argument
Genuine remorse – suicide attempts in custody
 NSWSC 1716
Killed father following argument – V died from blunt force trauma to the head and neck – both had been drinking – A said V taunting and baiting him - pattern between A and V for many years - history of physical altercations.
Schizophrenia - characterised by relapses of psychosis evidenced by auditory hallucinations, delusions and thought disorder.
Low end of objective seriousness.
Support of mother and family.