[2001] HCA 67
Director of Public Prosecutions (Cth) v De La Rosa (2010) 79 NSWLR 1
Source
Original judgment source is linked above.
Catchwords
[2001] HCA 67
Director of Public Prosecutions (Cth) v De La Rosa (2010) 79 NSWLR 1
Judgment (15 paragraphs)
[1]
JUDGMENT
On the afternoon of 27 June 2020, the offender murdered his girlfriend Liquin Pan, using a hammer and two knives, stabbing her at least 75 times in the face, head, neck, back, upper limbs and hands. He did this, intending to kill her.
Liquin was only 19 years old. She had met the offender in Shanghai and travelled to Australia in October 2018 to be with him. From the limited evidence I have seen, she seems to have been an attentive and loyal partner.
The murder took place in the apartment they shared in Wolli Creek. Shortly after he killed Liquin, the offender left their apartment, went to some internal stairs, and attempted to slice his left wrist open vertically. He then went to the fourth floor, climbed over the railing and jumped, landing on the footpath below. He sustained very serious injuries including an extremely severe traumatic brain injury, spinal cord injury, multiple leg and pelvic fractures and internal injuries.
The offender remained in the intensive care unit at St George Hospital until 5 August 2020. His ventilator was removed on 10 September 2020 and by 6 October 2020 he was able to speak both Mandarin and limited English. Before that time he had communicated by writing words on paper.
On 14 August 2020 he was asked by a mental health nurse if he remembered why he was in hospital and he wrote the words: "kill girl".
Whilst still in hospital he was cautioned and arrested on 20 January 2021 and was shortly after charged with Liquin's murder.
The offender was committed for trial in the Supreme Court on 3 February 2022. During the arraignment process, an issue was raised about his fitness to stand trial.
An inquiry into that issue commenced on 20 June 2022 before Wilson J. On 29 June 2022 the offender was found by her Honour to be fit to be tried: R v He [2022] NSWSC 847. That meant that her Honour concluded, having considered all of the relevant evidence, that despite his severe traumatic brain injury, the offender was able to understand the offence the subject of the proceedings, plead to the charge, exercise the right to challenge jurors, understand generally the nature of the proceedings as an inquiry into whether he committed the offence with which he is charged, follow the course of the proceedings so as to understand what was going on in a general sense, understand the substantial effect of any evidence given against the person, make a defence or answer to the charge, instruct his legal representative so as to mount a defence and provide his version of the facts to that legal representative and to the court if necessary, and to decide what defence he will rely on and make that decision known to his legal representative and the Court.
On 7 October 2022, the offender entered a plea of guilty to murder. It is common ground that this plea of guilty at that stage automatically entitles him to a 25% discount on his sentence.
There were delays in listing the sentencing proceedings while medical records were obtained and reviewed and experts retained to consider whether there were additional matters to place before the Court that may have a bearing on sentence.
Most of the facts relevant to sentencing were incorporated into a statement of agreed facts that were signed by the offender in January 2024, however there remains for me to determine a separate issue regarding whether the offender was operating under a mental illness, condition or impairment that had contributed to his offending in a material way.
The law recognises that distinct from cases where a person is so mentally ill that they cannot be held legally responsible for their crime, there are cases where the state of a person's mental health contributes to the commission of an offence in a material way. In such circumstances it may be that the offender's moral culpability is reduced, and so the need to denounce the crime may be less, with a consequent reduction in sentence. It also may be that in the specific circumstances, the need for emphasis on general and specific deterrence may be less, or an offender's time in custody may be more onerous for him because of poor mental health: Director of Public Prosecutions (Cth) v De La Rosa (2010) 79 NSWLR 1; [2010] NSWCCA 194 ("De La Rosa") at [177]. None of these principles are absolute. The Court must examine the relevant facts in order to determine whether in the specific case, the mental condition has the consequences contended for: Aslan v R [2014] NSWCCA 114 at [34] per Simpson J (as her Honour then was), Adams and McCallum JJ agreeing.
The offender asserts that he was suffering from a drug-induced psychosis caused by long-term nitrous oxide use and so at the time he murdered Liquin his mental illness contributed in a material way to the offending. Reports of Dr Furst, a psychiatrist, and Professor Christie, a pharmacologist, were tendered by the offender. Each expert gave evidence and was cross-examined.
The Crown contended that the offender was intoxicated by his own deliberate use of nitrous oxide at the time he murdered Liquin, and that it was not possible on the evidence to conclude on the balance of probabilities that drug-induced psychosis had a causal role in the offending. Self-induced intoxication is not permitted to be taken into account as a mitigating factor: s 21A(5AA) of the Crimes (Sentencing Procedure) Act 1999 (NSW) ("the Sentencing Act").
Nitrous oxide is able to be accessed over the counter in multi-packs of small silver cylinders known colloquially as "nangs", "hippy crack", "whippits" or "cannies". It provides a short acting "high", rapidly producing euphoria, visual and auditory hallucinations as well as, potentially, confusion and depersonalisation or derealisation after inhalation. Effects can resemble psychotic symptoms, similar to those produced by ketamine.
Studies indicate that there can be psychosis beyond the period of acute intoxication in individuals abusing large doses of nitrous oxide, particularly with regular misuse over prolonged periods.
There was evidence of nitrous oxide use and abuse by the offender. Large boxes of empty canisters were located in the apartment shared by the offender and Liquin, as shown in the crime scene photographs taken after the offender killed her.
Liquin had sent a photograph of the boxes to a friend the night before she was killed, saying "he had finished five boxes of gas in the last two days". This supports recent heavy use by the offender. He may also have been using nitrous oxide the night before he killed Liquin whilst with the Suns, and may have used it in the period between when he arrived home at about 1:51pm and when he killed Liquin, some time between 2:00pm and 3:23pm when the offender was found face-down on the street having jumped.
The issue is complicated by the evidence of lawfully recorded conversations with his parents and uncle during which they encouraged the offender to assert no memory of the events and to say someone else was responsible, which is what he in effect did do, when interviewed by doctors at a later point in time.
There was nothing in the agreed facts or the evidence tendered on sentence, that comprised or included a sworn or verified account by the offender as to his nitrous oxide use. A version given to Dr Furst, psychiatrist, in December 2022 by the offender was thought by Dr Furst to be untrue and a deliberate minimisation of the offender's nitrous oxide use.
[2]
Background facts
Turning to the background facts, the offender was born in 1999 in Beijing and was financially supported by his family. He is an only child. He was undertaking a pre-university course at Taylors College in Sydney which had to be successfully completed before he could commence a Bachelor of Commerce at Sydney University, his desired university course.
An affidavit of Ms Thorne, Compliance Manager at Taylors College, stated that the offender had commenced the "Foundation Course" on 4 February 2019 which required an upfront payment of $33,150.00. He did not achieve the minimum requirements to progress during 2019. He was permitted to enrol in a repeat semester in February 2020 at a further cost of $14,544.00. The results of that repeated course were due on 29 June 2020. There is evidence from the offender's friend Steve that the offender was anxious about this, and was concerned about passing the course.
Ms Thorne also explained in her affidavit that the offender was not meeting the minimum attendance requirements for his student visa, although she does not explain the potential repercussions of those failures.
The offender's entry to Sydney University had been deferred to 3 August 2020. He had not, by 29 June 2020, achieved the required marks for entry to that course. It is unclear on the evidence tendered on sentence whether he had become aware of that failure by the time he killed Liquin.
The offender had been in a relationship with Liquin for over two years. There was evidence of coercive control on the part of the offender. In a notebook found by police was a "contract", apparently signed by the offender and Liquin, that set rules around Liquin's trip to China in early 2019. It included amongst other things that she should "get rid of acne", not drink, not go to bars or clubs or do anything with people of the opposite sex. She must make sure the background on her phone remained unchanged and always "has the offender in it". She must never put her mobile phone on silent mode. The contract concluded: "The violation of any of the above rules will be regarded as crossing the line set by (Weijie He) and will indicate the disappearance of love and the fact that he no longer matters. End of relationship".
There were other signs of trouble in the relationship. A conversation (lawfully recorded by a hidden listening device) in October 2020 between the offender and his friend Ethan discussed the fact that the offender had required Liquin delete from her phone all the people she had known in Shanghai, including her ex-boyfriend. Anxu Liu also observed problems in the relationship including a two-to-three-hour argument in May 2020 between the offender and Liquin over Liquin talking to a boy on WeChat.
The agreed facts on sentence signed by the offender in January 2024, confirm the offender told his mother some time after January 2020 that he was angry at his girlfriend for lying about her family saying that they were wealthy, when they were not.
Recorded conversations between the offender and his mother in September and October 2020 also revealed a problematic attitude to his relationship with Liquin. The offender's mother described Liquin as "not wifey material" to which the offender replied: "She was very obedient, and she was pretty" and "She always followed my instructions. She dared not oppose me". He also said: "Panpan [Liquin's nickname] and I split the chores in half. If Panpan didn't do it, I'd beat her up", to which his mother replied: "Don't say that. Don't say that to police at all". The offender then said: "Ok. I didn't beat her up". His mother replied: "Panpan was badly attacked before she died. If you say that, police will suspect you even more. Don't say anything negative". The offender replied: "I loved her so much that I wouldn't touch her". His mother replied: "That's right. Say that. Police will come either tomorrow or the day after. Be careful. They won't be in uniform. Remember, anyone who's not in hospital uniform is police. Don't talk nonsense that's not in your favour".
Affidavits of friends of the offender, Lina and Lei Sun, were tendered. Neither were required for cross-examination. Lei Sun stated that the weekend before the murder whilst on a weekend away together, the offender told him that he had "invited her" (Liquin) from China to come to Australia, "but now I can't get rid of her".
The night before he killed Liquin, whilst out again with Lei and Lina Sun, the offender complained to Lina that he felt that he was "too good" for his girlfriend and asked to stay with them that night as he and Liquin were "having problems" and he did not want to go home. He told her that they had had an argument and he "needed a break" and that due to her having previously been with an older male, he did not want to be with her anymore and did not want to return home. He told Lei Sun that Liquin had dated an older man for money and because of this he did not want to be with her anymore.
[3]
The days leading up to the murder
In the days leading up to the murder there was some unusual behaviour by the offender upon which reliance is placed to suggest that he was entering, or experiencing, substance-induced psychosis.
On 25 June 2020, in a message exchange with his friend Steve, the offender said that he had not been sleeping and that he was nervous as his marks (for the repeated university entry course) were to be released on 29 June 2020.
On the night before the murder, the offender was picked up for dinner by Lei and Lina Sun. Despite the booking having been made by the offender for four people, the offender said that Liquin was not coming because she had university homework to do. Lina said that when they arrived to collect the offender, as he walked towards the car he did not look good, he did not smile, and his face looked "quite grey". Later the offender said he had a cold. He was wearing a long black trench coat, black pants and boots.
Lina observed during dinner at a restaurant at the casino that the offender took his jacket on and off and was constantly sweating. He left the table to visit the bathroom on multiple occasions. He looked at her in a strange and aggressive way. He made a number of short statements and then changed the subject saying things like: "I want to destroy everything so I can rebuild it", "I don't trust anyone in this world", "my girlfriend wants to commit suicide" and beating his chest saying: "We are connected, you understand me". He claimed to have some sort of power in his body which he could not control and "may explode and be reborn". He also said: "If I wasn't with you both I probably would have been dead".
He asked Lina if she would have someone investigated in China, claiming that "a man in his 50s" had "sexually attacked" a 14-year-old girl.
Both Lei and Lina observed the offender to quickly drink an entire bottle of wine during dinner. He then vomited into a bag whilst still at the table. After dinner he asked them to come with him to gamble in the casino, but they declined.
The offender went with Lina and Lei to their home unit and a bed was made up for him. According to Lei, the offender acted in a strange and agitated way whenever his girlfriend was mentioned.
At one point the offender said to Lina (while Lei went to the car to fetch something): "Have you got any gas?". She said: "No I don't. How long have you been using gas?" he replied: "Since about 2015". She said: "You need to stop using this, it is very bad for you, and this is a long time to use it". He said: "I need to fully understand before I quit it." She replied: "you know it already. You should stop it right now….".
The three of them talked and drank tea for a few hours and then went to bed, with the offender set up to sleep in the spare room. Lina felt anxious about him and spoke with Lei about the offender's behaviour. They put an object against the door to their room so that they would be alerted if he came in.
At 3:04am Lei received a text from Liquin. Liquin was using the offender's phone (which he had left at home the evening before), asking whether the offender was with them stating: "It's just that I am a little worried because it's his first time he hasn't come back home this late". Lei replied: "Don't worry. Go have a rest early".
Overnight Liquin had written several messages to friends expressing her worries about the offender's whereabouts. She said that she had been unable to contact him as he had left his phone at home. She wrote to Steve that the offender had "finished 5 boxes of gas in the past 2 days". Steve replied: "How come he started doing hippy crack" to which she replied: "He was feeling blue days ago. I believe he won't leave us behind".
To another person Liquin wrote: "He's under a lot of pressure from his family! Look at these canisters of gas he finished the past two days!" attaching a photo which shows the large boxes full of nitrous oxide canisters (the boxes appear to contain hundreds of canisters).
Back at the Sun's unit the following morning there was further bizarre behaviour by the offender. He requested Lei give him $30,000.00. He damaged a toy model car by smashing it onto a table, threatening to "destroy" them (the Suns). He then insulted them, asking them to help him put on his shoes claiming he was "so weak" and that he could not stand. The Suns made up a story to get the offender to leave, and arrangements were made to drive him home.
Lina and Lei confirmed that there was not much talking during the drive home, but Lina stated that the offender said some odd things. When Lei attempted to tell the offender that he was lucky to have the opportunities he had, the offender shouted at him to "shut up".
The offender was dropped outside his building at about 1:35pm. He made multiple attempts to enter the building, seeming not to remember the password. He was seen on level 11 knocking on a door and wandering up and down the hallway. CCTV shows that he exited the building at 1:48pm and re-entered at 1:49pm.
At 1:51pm Liquin messaged Steve saying: "He's home." Steve replied: "Where did he go" and Liquin replied: "Don't know. He's been like another person since he got back". She then withdrew that message at 1:55pm and sent another message: "Don't know. He wants to be left alone".
At 2:00pm Liquin wrote to her friend Eric: "Eric do you have any friend who can book a flight ticket back home?". Then at 2:02pm she wrote: "I've been waiting for him since last night" then withdrew that message and five seconds later wrote: "He's just got home", then withdrew that message and wrote: "Jack's home now". At 2:04pm she also messaged another person: "Wake up yet".
At 2:04pm Liquin's phone was used to google search: "people are brainwashed". This was the last time her phone was used.
[4]
The attack
At some time between 2:04pm and 3:23pm, the offender attacked Liquin with at least two knives and a hammer, stabbing and slashing her at least 75 times to her face, head, neck, upper limbs and hands with the intention of killing her.
Her blood was later found smeared on the sofa, on the floor near the TV, and across the four panels of the folding door to the second bedroom. There were two overturned chairs in the dining area. Liquin was found by police dead, curled up in foetal position near the overturned chairs in a large pool of her own blood and surrounded by hundreds of empty nitrous oxide canisters.
Judging by the injuries noted on post-mortem it was clearly an extremely ferocious attack. Liquin had 39 stab wounds to her head and face. She had bruising and abrasions around her lips, mouth, chin and below both eyes. She had fractures to her skull and had suffered a subarachnoid haemorrhage. There were nine stab wounds to the back of her neck, one of which entered the spinal canal and penetrated through the spinal cord dura. There were signs of fractures to her hyoid cartilage which indicated a strangulation-type injury. There were 10 wounds to her back, and 17 to her arms, most of which were defensive wounds to her hands. The offender's DNA was under her fingernails.
The forensic pathologist's opinion was that the cause of death was the stab wounds to her head and neck.
The abject terror, confusion and agony she must have experienced during this attack is unimaginable.
[5]
The aftermath
After the attack the offender left the unit leaving his jacket, shoes and personal effects behind. He closed the door, causing it to lock. He tried to open a window at the end of the corridor next to unit 901, perhaps to try and jump out, but it did not open far enough. He went into the fire stairs at level 9, and walked up and down the stairs from level 10 to level 1 for a period of time, evidenced by his footmarks in Liquin's blood on the stairs. He ripped metal tags from some fire extinguishers in the stairwell and made what was possibly a suicide attempt by slicing his left wrist open vertically.
Some time prior to 3:23pm he exited the stairwell at level 4, went to the courtyard, climbed over a glass balustrade and jumped, falling four storeys onto the footpath next to Chisolm Street. Passers-by contacted 000 at 3:23pm. Police attended to find the offender face down, unconscious and breathing with a large deep wound to his left wrist and dried blood on his hands.
He was conveyed to hospital with serious life-threatening injuries. He remained in ICU until 5 August 2020. From 12 August 2020 he was able to communicate by mouthing, using hand gestures and writing on a white board. He was removed from his ventilator in September. By October 2020, he was able to speak, and spoke in both Mandarin and limited English.
There is evidence that by September 2020 the offender's mother was regularly visiting her son in hospital and actively coaching him about what to say to the authorities about how Liquin had died:
"If they tell you to tell the truth, just tell them that you don't know. Tell them that you can't remember".
and
"This old bitch comes quite often. They say she's a psychiatrist. Whatever they ask you, just tell them you know nothing, just don't say anything. When the old bitch comes to speak with you, don't say anything. Ok? Tell them you know nothing. You hear me? When that old bitch asks you questions say nothing. Just say you don't remember. Ok? No matter who asks you questions about that, don't say anything. Remember?".
The offender is observed by the hidden surveillance device to show his thumb by way of reply.
On 20 September 2020, the offender's father was recorded saying the following to the offender:
"Hopefully the case will be over soon it would be best if you not be involved in it… currently you can't talk and you are still not completely alert. That's why police haven't come to you yet. They will come and talk to you once you are sober. Just like what I said to you previously, if you really did it, then, there's always something that you forgot in your life that you can never remember. Just let it be forgot. You have to come up with a script by yourself. We can't help you on that. The key issue is how to let people believe your story. If you didn't do it, that a different topic. If you did it, you must come up with a perfect script. You will have to write and play the script so that everyone would believe you. Otherwise, you are done. If you did it, you can forget it because you sustained injury in your head. That makes sense. If some bad guy did it, you need to remember what happened. Do you understand me? Now squeeze my hand if you did it..".
The offender was observed on surveillance devices to move his hand slightly, but it is unclear whether he squeezed his father's hand or not.
A number of other similar "coaching sessions" were recorded during September and October 2020 involving the offender's mother, father and an uncle who spoke to the offender via WeChat about what the offender should say when interviewed by police, including the propagation of the idea of another person being responsible for killing Liquin and "pushing" the offender over the balcony.
On 14 October 2020, the offender was to be interviewed by a hospital neuropsychologist. His mother was recorded on a listening device as whispering the following to him before she was required to leave the room to allow the interview to proceed:
"Don't say anything to them. Just tell them you were both harmed by someone else. If the interpreter asks you, say so as well. Don't talk nonsense or you'll be taken away. Just say "Please help me and catch the bad guy. The bad guy harmed us both". Remember this. Don't say the bad guy is in China. Just say it was someone harmed you. Don't tell them I told you anything. If they ask you, just say I don't know. Mum didn't tell me anything".
Of course what his parents and uncle said to the offender does nothing more than provide background. The offender never did provide an interview to police. However, when assessed by the neuropsychologist, Susan Pulman, in December 2021, when she asked him what caused him to fall from the balcony, he said:
"I know that my girlfriend was harmed by some bad people, they kill her".
The offender denied to Ms Pulman that he was in gaol, stating that he was "in rehabilitation" as part of his recovery. When she told him that he had been charged with an offence he replied: "What crime, I haven't committed a crime".
The offender told Dr Martin, psychiatrist, in December 2021 that his girlfriend had "been attacked by others". When asked why he had fallen he said:
"I can't remember - someone sabotaged me, and they sabotaged my girlfriend too. They say I killed my girlfriend but me and my girlfriend are victims, we were harmed by some bad people".
When interviewed by Dr Furst in December 2022 and asked what happened that led to the death of his girlfriend, the offender said:
"I forgot. My mother tell me my girlfriend is gone".
The offender told Dr Furst that "other people" or a group of people "hurt his girlfriend" and "pushed him" from the building, stating that he did not know who would do this. He repeated at different points in his interview with Dr Furst that "someone else stabbed her".
I do not need to make a formal finding that these assertions are untrue. By his guilty plea, and by his signing the statement of agreed facts on 31 January 2024, the offender has acknowledged that he is the person who viciously attacked and murdered Liquin, and that he did that, intending to kill her.
[6]
Victim impact statement - Mr Zewu Pan, Liquin's father
Before moving on to state the principles of sentencing and evaluating the evidence, making my findings and imposing sentence, I need to pause and reflect on the heartbreaking statement provided to the Court by Mr Pan, Liquin's father. He and his wife welcomed Liquin as their first child in 2000. They were ecstatic and poured all their love and care upon her. They were happy to see her progress from their small rural village in the Guangdong Province, China to receive an education and enrich herself and expand her horizons.
Mr Pan described how the news of Liquin's death brought devastation and crushing and immeasurable pain to the family. Liquin's mother cannot accept it is true. Liquin's younger brothers and sisters have not been told because her parents fear the effect it will have on them. Festivities and family reunions that used to be occasions for joy are torture now because of the unspeakable grief that affects those events.
Liquin is remembered by her father as a person who "embraced this world with kindness and affection". As her father says: "She should have been experiencing the best time of her life, but her young life was barbarically cut short by such a heinous crime".
The Court conveys its sincere condolences to the family of Liquin Pan and to the people who love her and miss her.
[7]
Principles of sentencing
The purposes of sentencing as set out in s 3A of the Sentencing Act are:
(a) to ensure that the offender is adequately punished for the offence,
(b) to prevent crime by deterring the offender and other persons from committing similar offences,
(c) to protect the community from the offender,
(d) to promote the rehabilitation of the offender,
(e) to make the offender accountable for his or her actions,
(f) to denounce the conduct of the offender,
(g) to recognise the harm done to the victim of the crime and the community.
The maximum penalty for the offence of murder is life imprisonment: s 19A(1) Crimes Act 1900 (NSW). If the Court does not impose a life sentence, the Court may impose a sentence of imprisonment for a specific term: s 21(1) Sentencing Act. A standard non-parole period of 20 years applies for the crime of murder. I am required to impose a life sentence only if I am satisfied that the level of culpability involved in the commission of the offence is so extreme that the community interest in retribution, punishment, community protection and deterrence, can only be met if a life sentence is imposed: s 61(1) Sentencing Act. I am not so satisfied. However, a significant term of imprisonment should be and will be imposed.
My task is to make findings about the objective and subjective facts relevant to sentencing the offender. Any findings that are adverse to an offender must be arrived at beyond reasonable doubt: Cheung v R (2001) 209 CLR 1; [2001] HCA 67 at [14] per Gleeson CJ, Gummow and Hayne JJ. Any findings that favour the offender must be on the balance of probabilities: The Queen v Olbrich (1999) 199 CLR 270; [1999] HCA 54.
Before proceeding to an assessment of the objective seriousness of the offending, I need to examine the evidence relevant to the question of whether the offender was suffering from a mental condition or illness at the time he killed Liquin and if so, whether that condition contributed to the commission of the offence in a material way.
[8]
Did the state of the offender's mental health contribute to the commission of the offence
Professor Christie, an expert pharmacologist specialising in the actions of drugs and alcohol on brain function, stated that there is evidence that with nitrous oxide use, there can be psychosis beyond the period of acute intoxication in individuals abusing large doses of nitrous oxide, particularly with regular misuse over prolonged periods.
Professor Christie concluded that nitrous oxide use may have contributed to the offender's mental state, because the pattern of use appears to have been very heavy, given the message from Liquin to her friend that he had used five boxes of nitrous oxide in the last two days. If each box contained 50 canisters, Professor Christie reasoned this would be over 250 canisters in two days which is suggestive of a severe, dependent pattern of use. There was also the photo of hundreds of canisters at the crime scene. If they had in fact accumulated over the days before the murder because of use by the offender, then this suggests a very heavy pattern of use.
Professor Christie concluded that it was possible that the offender was suffering from a drug-induced psychosis caused by heavy use of nitrous oxide in the days to weeks or months prior. He cites support for this as Liquin's account of the empty canisters, what Lina and Lei Sun described of the offender's behaviour on the night before he killed Liquin, and the analyses carried out in the relevant literature.
Professor Christie said that the opinions of the psychiatrists that the offender did not display signs of psychosis or have a long-term history of schizophrenia on later assessment does not discount the possibility of a drug-induced psychosis at the time of the murder, as it would be expected to resolve fully in the days to weeks following the incident whilst he was hospitalised.
Professor Christie also placed reliance on the theoretical correlation between nitrous oxide abuse and vitamin B12 deficiency and adverse neurological effects. St George Hospital records for the offender indicated a low vitamin B12 level on blood chemistry performed on 8 July 2020, 11 days after the murder. Professor Christie described this as "close to the lower extreme of the stated normal range". The offender was administered vitamin B12 over the following two weeks. Professor Christie concluded that the very low vitamin B12 levels shown in the hospital records strengthened his previously expressed opinion that the offender's behaviour at the time could have been influenced by the immediate effects of overuse of nitrous oxide and/or immediate effects combined with a drug-induced psychosis produced by longer term metabolic disturbances caused by nitrous oxide overuse over days to weeks or months.
Dr Robertson, pharmacologist, was not convinced that the B12 level had the significance imported to it by Professor Christie. Dr Robertson noted that the B12 level was in the low end of normal range, and as such does not indicate it caused any physical symptoms, or was of any clinical significance. Dr Robertson observed that it was unclear if the treatment provided in hospital may have caused any effect on the B12 levels, nor what the offender's usual B12 level was. If he was in fact experiencing symptoms of low or deficient vitamin B12, it is likely that he would have been showing symptoms for weeks or months prior to the incident such as headaches, fatigue, impaired balance, neuropathy, impaired memory, depression and confusion. Dr Robertson concluded that it was mere speculation that the offender was experiencing the effects of a low vitamin B12 level at the time of the offence.
Dr Furst, psychiatrist, concluded based on the Crown Case Statement, the statements of Lina and Lei Sun, and the interviews he conducted with the offender in October and December 2022, that the offender was "mentally disturbed in relation to his thinking and behaviour in the days preceding the offending". Dr Furst said that the message Liquin sent just prior to being killed was also suggestive of a major change in the mental state or behaviour of the offender. Dr Furst concluded that there was little in the way of realistic, (non-psychotic), motivation for the offender to stab Liquin in the manner set out in the agreed facts. The evidence of hundreds of empty nitrous oxide canisters and the report to Lina Sun that he had been using nitrous oxide since 2015, pointed towards a pattern of heavy use for some years, or at least for some significant period of time.
Dr Furst concluded that it was more likely than not that the offender was suffering from both acute and chronic effects of nitrous oxide at the time of the offending such that he was delusional, highly disturbed and disorganised in his behaviour and was suffering a substance-induced mental disorder, often referred to as a drug-induced psychosis.
Dr Furst also concluded that the offender was not truly amnesic for the offending in question, even given the very serious head injury. In the context of the offender killing his girlfriend while psychotic, and then attempting to kill himself, Dr Furst concluded that the offender was having difficulty coming to terms with his extreme actions.
Dr Martin, psychiatrist, concluded that the offender's behaviour was consistent with a transient psychotic mental state, with thought disorder. The things he said to the Suns are consistent with disinhibition, anger and hyperarousal. Dr Martin concluded that it was likely that the offender was heavily intoxicated and experiencing a transient delirium and an acute confusional state, manifesting with psychotic phenomena, in the time leading up to the offending and directly related to the offending.
Dr Martin also concluded that issues of jealousy, control and anger directed towards Liquin were potentially relevant to underlying motivation for what seemed to be a rageful attack in a delirious and disinhibited mental state while under the influence of nitrous oxide.
Dr Furst and Dr Martin gave evidence at the sentence hearing and were cross-examined. Their opinions taken at face value appear similar, although there is different emphasis. The causal emphasis of Dr Furst is on drug-induced psychosis causing delusions, whereas Dr Martin's focus is on a transient delirium while heavily intoxicated but manifesting with psychotic phenomena.
I have concluded on the balance of probabilities that the offender, at the time he killed Liquin, was suffering from a self-inflicted transient drug-induced psychosis, alternatively described by Dr Martin as a transient delirium manifesting while intoxicated, with psychotic phenomena, and that in that state, he directed his rage to Liquin, killing her in a frenzied and merciless attack. The evidence does not permit me to conclude that the offender had in fact probably used (the very short-acting) nitrous oxide in the immediate period before he killed Liquin.
However, because the mental state of the offender at the time he killed Liquin was inextricably bound up with his deliberate and repeated use and abuse of nitrous oxide, I have concluded that this is a circumstance where the objective seriousness of the offending is only marginally reduced. Although there is no evidence that the offender had a detailed understanding that the abuse of nitrous oxide could lead to a transient psychosis or delirium with psychotic phenomena, he knew of, and repeatedly sought, out its intoxicating and disinhibiting effects.
His moral culpability is also mildly reduced, noting however that it is appallingly self-indulgent to deliberately use and abuse an intoxicating inhalant to remove oneself from reality and responsibility for one's own actions. This is what the offender did. I cannot exclude entirely the indicators that the attack was directed at Liquin as part of the offender's own unjustified dissatisfaction with her, and that he was taking out on her his rage at his own failures and inadequacies, like so many men who murder their domestic partners, but I cannot make a finding beyond reasonable doubt that this was the, or a precipitant or motivating factor for this particular attack during which he murdered his domestic partner.
The need for the sentence to reflect general deterrence remains an important factor given that deliberate substance abuse played a role. There is no diagnosed ongoing mental illness of any kind, but there are extensive physical disabilities which I will address in the subjective case and in my special circumstances finding. These disabilities will clearly make the offender's time in custody more onerous.
[9]
Objective gravity of the offence
The attack was extremely violent, and given the number of stab wounds and injuries, prolonged. There were defensive wounds to Liquin's arms and hands. The attack involved the use of three weapons. It was merciless. The offender stabbed and slashed her at least 75 times. The attack would have taken some time to complete. The tip of one of the knives remained embedded in Liquin's scalp. He clearly intended to kill her.
This is very serious offending, and even taking into account my findings about the offender's mental state, the offending is still above the mid-range of seriousness for offences of this type. The forensic evidence suggests that there was a chase and a struggle in the unit. The defensive wounds to her hands and arms demonstrate that Liquin fought for her life, sadly to no avail.
[10]
Subjective case
The offender is now 24 years old. He was born in China, the only child of wealthy parents who are retired journalists. His mother came to Sydney after these events and remains living here, visiting her son weekly. His father remains in China.
The offender speaks Mandarin. He attended primary and high school in China, with an interest in English and languages. He had a mild depressive disorder in his early to mid-teenage years and was treated with an anti-depressant whilst in high school for a period of about twelve months in total.
He came to Australia in September 2018 to undertake a pre-university course at Taylors College and planned to study economics at Sydney University. He was a young man of at least average intelligence but was failing the pre-university course.
It is relevant and necessary to the sentencing exercise that I take into account the offender's physical injuries and disabilities that resulted from his actions on 27 June 2020. It was not submitted that this situation should be considered "extra-curial punishment", but it is still relevant to the wider question of the hardship occasioned to the offender from being in custody while experiencing these significant disabilities. Where matters of that kind will have the result that imprisonment will be a greater burden on the offender, then they warrant leniency: R v Quinn (No. 3) [2016] NSWSC 1699 at [52] per Beech-Jones J referring to R v Smith (1987) 44 SASR 587 at 589.
The offender sustained spinal fractures, pelvic fractures, limb fractures and significant internal injuries. He required a number of surgeries, and a long period of rehabilitation in hospital. He requires further left foot surgery, scheduled for 2025. He has an extremely severe traumatic brain injury with a 69-day period of post-traumatic amnesia. He has ongoing short-term memory and planning issues, and limits to his executive functioning.
He requires assistance with showering and bladder and bowel function. He has an indwelling catheter for life. He has a need for a (self-propelled) wheelchair for movement although he can walk assisted and is encouraged to do so. He requires long-term care. He is on multiple medications to manage infection risk, and his orthopaedic and spinal cord and brain injuries. These matters will no doubt cause his time in custody to be significantly more onerous than if he was uninjured. These matters warrant leniency and I have adjusted the sentence and in particular, the non-parole period, accordingly.
[11]
Special circumstances
Counsel for the offender contended that given the offender's youth and the serious, albeit self-inflicted, injuries, I should find special circumstances and reduce the non-parole period from the usual statutory ratio of 75%. Countering that submission is the need to ensure that the non-parole period reflects the seriousness of the offending. I have decided, given the offender's young age and the extensive physical difficulties and incapacities he now has, a substantial adjustment to the non-parole period ratio to head sentence is warranted.
[12]
The guilty plea, absence of remorse, prospects of rehabilitation and risk of reoffending
The guilty plea entitles the offender to a 25% reduction in sentence.
The guilty plea does not, in the circumstances of this case, indicate remorse. There is no sign of remorse. In the face of a Crown case that is overwhelming, I give no weight to the guilty plea as an indication of remorse in circumstances where the offender could have, but has not, expressed any remorse at all. He has made no acknowledgement of what he has done. He has shown no sign of being sorry for killing this innocent young woman, and has maintained the fiction to those he spoke to that it was not him who killed Liquin.
Given this maintained attitude, I cannot conclude that the offender has good prospects of rehabilitation.
The offender's extensive physical disabilities will greatly limit his physical ability to reoffend. He is unlikely to reoffend. This is a mitigating factor I have taken into account: s 21A(3)(g).
[13]
Aggravating and mitigating factors
The use of knives and a hammer were submitted by the Crown Prosecutor to amount to an aggravating factor under s 21A(2)(c) of the Sentencing Act. I am mindful that I have already taken into account the use of those weapons in my assessment of objective seriousness, and so make no separate allowance for their use as a separate aggravating factor.
The offending occurred in Liquin's home where she was entitled to feel safe. This is an aggravating factor: s 21A(2)(eb).
I have concluded that the offence was not planned. This is a mitigating factor: s 21A(3)(b).
The offender has an otherwise clean record and to that extent, he can be considered to be a person of good character: s 21A(3)(f). This and the obvious lack of planning, are mitigating factors that I have taken into account.
[14]
Conclusion and sentence
Weijie He, you are convicted of the murder of Liquin Pan.
I sentence you to a total period of imprisonment for a term of 20 years comprising a non-parole period of 13 years commencing on 20 January 2021 and expiring on 19 January 2034, with a balance term of 7 years commencing on 20 January 2034 and expiring on 19 January 2041.
The earliest date upon which you will be eligible for release to parole is 19 January 2034.
I am obliged to tell you of the existence of the Crimes (High Risk Offenders) Act 2006 (NSW), which applies to serious offences, including the offence of murder for which you have just been convicted and sentenced. This means that the State can apply to the Supreme Court for an order that you continue to receive supervision or to be held in detention at the end of your sentence if the Court considers you to be a high-risk offender who poses an unacceptable risk of committing a serious offence.
[15]
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Decision last updated: 31 May 2024