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[2026] NSWSC 1003
Supreme Court of NSW
2026-08-21
Dhanji J
Original judgment source is linked above.
Source: NSW Caselaw (www.caselaw.nsw.gov.au). Converted to plain text by ZoeLaw. Not the official version.
Medium Neutral Citation: R v Delaney [2026] NSWSC 1003
Hearing dates: 21 August 2026
Date of orders: 21 August 2026
Decision date: 21 August 2026
Jurisdiction: Common Law - Criminal
Before: Dhanji J
Decision: (1) On the charge that the accused, between 2 June 2020 and 9 June 2020, at Cambridge Park in the State of New South Wales, did murder Gabriella Delaney, I return a special verdict of act proven but not criminally responsible.
(2) Pursuant to s 33(1)(b) of the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW) (the Act), the accused is to be detained in a correctional facility, or at such other place as may be determined from time to time by the Mental Health Review Tribunal until released by due process of law.
(3) Pursuant to s 34 of the Act, the accused is referred to the Mental Health Review Tribunal.
(4) Pursuant to s 30N(4) of the Crimes (Sentencing Procedure) Act 1999 (NSW), the victim impact statements of Rebekah Delaney, Jayleb Delaney, Kayla Tompkins and Daniel Delaney are to be provided to the Mental Health Review Tribunal.
(5) The Registrar is to notify the Mental Health Review Tribunal, as soon as it is practicable, of the making of these orders and is to provide to the Tribunal the following documentation:
(a) A copy of my reasons for verdict and the making of these orders;
(b) A copy of the exhibits tendered in these proceedings, including the agreed facts and the reports of Dr Anthony Samuels and Dr Olav Nielssen.
(6) The Registrar is to notify the Justice Health and Forensic Mental Health Network, as soon as is practicable, of the making of these orders and is to provide to the Justice Health and Forensic Mental Health Network the following documentation:
(a) A copy of my reasons for verdict and the making of these orders;
(b) A copy of the exhibits tendered in these proceedings, including the agreed facts and the reports of Dr Anthony Samuels and Dr Olav Nielssen.
Catchwords: CRIME – murder – defence of mental health impairment – where parties agree defence is available – hearing pursuant to of the s 31 Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW) – Court satisfied defence is available – special verdict entered – act proven but accused not criminally responsible – victim impact statements
Legislation Cited: Crimes (Sentencing Procedure) Act 1999 (NSW), ss 30L, 30N
Crimes Act 1900 (NSW), s 18
Criminal Procedure Act 1986 (NSW), s 132
Evidence Act 1995 (NSW), s 191
Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW), ss 4, 28, 31, 33, 34
Cases Cited: Delaney v R [2025] NSWCCA 76
R v Delaney [2022] NSWSC 1327
R v Lim [2026] NSWSC 378
R v Siemek (No. 1) [2021] NSWSC 1292
R v Tonga [2021] NSWSC 1064
Category: Principal judgment
Parties: Rex (Crown)
Lucas Christian Delaney (Accused)
Representation: Counsel:
V Garrity (Crown)
T Quilter SC (Accused)
Solicitors:
Solicitor for Public Prosecutions (Crown)
Legal Aid NSW (Accused)
File Number(s): 2020/00171177
Publication restriction: Nil
Lucas Christian Delaney has been arraigned and has pleaded not guilty to a charge that he, between 2 June 2020 and 9 June 2020, at Cambridge Park in the State of New South Wales, did murder his sister, Gabriella Delaney, contrary to s 18(1)(a) of the Crimes Act 1900 (NSW).
This matter is before me today as a hearing pursuant to s 31 of the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW) (the Act). I pause to note that while the offence with which Mr Delaney has been charged occurred before the commencement of the Act on 27 March 2021, for the reasons set out by Wilson J in R v Tonga [2021] NSWSC 1064 (“Tonga”) at [6]-[10], the legislative scheme applies to offences alleged to have been committed prior to that date where the proceedings before this Court were commenced following the commencement of the Act. Based on the reasoning in Tonga, the Act applies to this matter.
Section 31 of the Act allows me to return a special verdict of act proven but not criminally responsible where the prosecution and the defence agree that the proposed evidence in the proceedings establishes a defence of mental health impairment, the accused is legally represented and the Court, after considering the evidence, is satisfied the defence is established. The first two matters are satisfied. It therefore remains a matter for the Court to consider the evidence and decide whether the defence is established. The “proposed evidence” at trial was tendered before me for this purpose.
The matter has a somewhat protracted history. On 9 June 2020 the accused was arrested in relation the murder of Ms Delaney. On 22 April 2022 he pleaded guilty in the Penrith Local Court and on 3 June 2022 adhered to that plea in this Court.
On 19 October 2022 the accused was sentenced by Garling J to imprisonment for 21 years commencing on 9 June 2020 and expiring 8 June 2041, with a non-parole period of 15 years and 9 months due to expire on 8 March 2036: R v Delaney [2022] NSWSC 1327.
On 1 February 2023 the accused filed a notice of intention to appeal and on 28 November 2024 filed a notice of appeal. The accused sought leave to appeal his conviction on the sole ground that a miscarriage of justice was occasioned because the accused pleaded guilty on the basis of expert opinion evidence and legal advice that misunderstood the definition of “mental health impairment” under the Act. On 13 June 2025 the Court of Criminal Appeal (Davies J, Harrison CJ at CL and Weinstein J agreeing) granted leave to appeal and upheld the conviction appeal, quashed the conviction, granted the accused leave to withdraw his plea of guilty and remitted the matter to this Court for retrial: Delaney v R [2025] NSWCCA 76 (“Delaney v R”).
The accused was arraigned before Yehia J in this Court on 12 December 2025 where he entered a plea of not guilty to murder. An order for the accused to be tried by a judge alone was made on that date by consent: Criminal Procedure Act 1986 (NSW), s 132.
The trial was set to commence before me on 17 August 2026. On 14 August 2026 the Court was informed that the Crown and counsel for the accused had agreed that the proposed evidence in the proceedings established a defence of mental health impairment and a short adjournment was sought to finalise the relevant materials. As such, the matter proceeded before me today by way of hearing pursuant to s 31 of the Act.
An agreed tender bundle was provided, comprising the following:
Statement of agreed facts pursuant to s 191 of the Evidence Act 1995 (NSW);
a psychiatric report prepared by Dr Anthony Samuels dated 24 February 2022;
a psychiatric report prepared by Dr Olav Nielssen dated 22 February 2024;
a psychiatric report prepared by Dr Samuels dated 10 March 2025;
a psychiatric report prepared by Dr Nielssen dated 15 April 2025;
redacted conference notes with Dr Samuels dated 22 July 2026;
an email from Dr Samuels dated 17 August 2026; and
a further statement of agreed facts dated 20 August 2026.
The Court must first be satisfied that the physical elements of the charged offence have been proved by the Crown beyond reasonable doubt before considering the availability of the defence of mental health impairment: see Tonga at [15]; R v Siemek (No. 1) [2021] NSWSC 1292 at [16]; R v Lim [2026] NSWSC 378 at [19].
On the basis of the agreed facts tendered for the purposes of this hearing, which are summarised below, I am satisfied the physical elements of the offence of murder have been proved beyond reasonable doubt.
Mr Delaney and Ms Delaney were biological siblings. They had a close relationship, sharing a granny flat on a property in Cambridge Park. Their brother, Daniel Delaney, and his wife, Kayla Tompkins, lived in the main dwelling on the property. Their cousin, Jayleb Delaney, lived in a separate dwelling on the property.
On 3 June 2020 Mr Delaney and Ms Delaney were at home in the granny flat. Jayleb visited the granny flat in the afternoon after returning home from work. Jayleb observed Mr Delaney and Ms Delaney to be interacting normally and had a short conversation with them both before leaving between five and ten minutes later. He then returned to his own unit, which was around 8 metres away from the granny flat.
Sometime after Jayleb left, Mr Delaney struck Ms Delaney repeatedly to the head with a hammer, causing her death.
At some point after killing his sister, the accused went to Jayleb’s flat and sat on a chair across from him. Jayleb thought the accused looked as though something was wrong and the following exchange occurred:
“[Jayleb]: Are you right, do you need a cry, do you need a hug?
[Mr Delaney]: No. I am gonna go out for a couple hours, days.
[Jayleb]: Are you going to go on one of your benders?”
The accused laughed this off. Jayleb said he would go and hang out with Ms Delaney, to which Mr Delaney replied that she had gone to a friend’s house. Jayleb then offered to feed the dogs which the accused declined.
Between 3:50pm and 4:00pm on 3 June 2020, a total of $5,300 was transferred from the accounts of Ms Delaney to an account controlled by Mr Delaney.
That evening Mr Delaney stayed at a friend’s house where they smoked ice and stayed up throughout the night.
Over the following days, the accused was captured on CCTV withdrawing $2000 from the account to which the money from Ms Delaney’s accounts had been transferred. These withdrawals were made via automatic teller machines on three separate occasions. He also used money from this account to pay for accommodation on two separate nights.
On 4 June 2020 Mr Delaney checked into a hotel where he stayed the night.
On 5 June 2020 the accused return to his granny flat where he showered and got changed. He subsequently walked towards the Cambridge Park shops where he encountered Ms Tompkins, who enquired about Mr Delaney’s absence. Mr Delaney said he was “just going to the shops and probably won’t be home after that. I’ll probably be home over the weekend”.
That evening Mr Delaney checked into another hotel. Two of his friends joined him at the hotel and they smoked cannabis and ice.
On the afternoon of 6 June 2020 Mr Delaney checked in and spent the night at a different motel.
On 7 June 2020 Mr Delaney presented at Cumberland Hospital where he was voluntarily admitted. Mr Delaney told police, who had been called as he was in possession of cannabis on his arrival at the hospital, that he admitted himself due to drug use.
Jayleb visited Mr Delaney in hospital twice. On the second visit, on 8 June 2020, Jayleb asked Mr Delaney if he knew where Ms Delaney was, to which Mr Delaney said “no”.
Ms Delaney was reported missing to Penrith Police Station by her father, Ross Delaney, at 9pm on 8 June 2020. Her body was discovered in the granny flat shortly after and a report was made to police at 9:25pm.
At 10:50am on 9 June 2020 the accused was arrested at Cumberland Hospital and charged with the murder of Ms Delaney. On the way to the police vehicle, the accused asked Detective Sergeant Murphy, “she isn’t dead, is she?”.
28 Defence of mental health impairment or cognitive impairment
(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).
4 Mental health impairment
(1) For the purposes of this Act, a person has a mental health impairment if—
(a) the person has a temporary or ongoing disturbance of thought, mood, volition, perception or memory, and
(b) the disturbance would be regarded as significant for clinical diagnostic purposes, and
(c) the disturbance impairs the emotional wellbeing, judgment or behaviour of the person.
(2) A mental health impairment may arise from any of the following disorders but may also arise for other reasons—
(a) an anxiety disorder,
(b) an affective disorder, including clinical depression and bipolar disorder,
(c) a psychotic disorder,
(d) a substance induced mental disorder that is not temporary.
(3) A person does not have a mental health impairment for the purposes of this Act if the person’s impairment is caused solely by—
(a) the temporary effect of ingesting a substance, or
(b) a substance use disorder.
If the defence has been established on the balance of probabilities, there must be a special verdict of act proven but not criminally responsible pursuant to s 31 of the Act.
The return of the special verdict has the consequence that the accused is not liable to be found guilty and sentenced for the crime charged. He could either be released conditionally or unconditionally, or detained. That decision involves a consideration of whether the accused poses a risk to himself or to others. Detention can be in a prison or a secure hospital or similar facility. There would be regular reviews by the Mental Health Review Tribunal ("the Tribunal"). The detention would be until such time as the Tribunal determines that the safety of the accused or that any member of the public would not be seriously endangered by the release of the accused.
The agreed facts establish the accused caused the death of his sister, Ms Delaney, by striking her with a hammer. The primary issue relates to Mr Delaney’s mental state at the time.
Dr Samuels, a consultant forensic psychiatrist, was retained by the Crown to prepare an expert report for the purposes of, among other things, assisting in determining the availability of the defence of mental health impairment. Dr Nielssen was engaged by the defence to prepare a psychiatric report for use in relation to Mr Delaney’s appeal proceedings with respect to that same issue. As a result, I have ultimately had the benefit of two reports prepared by Dr Samuels, supplemented by redacted notes of a conference between Dr Samuels and representatives for the Crown which was followed by an email from Dr Samuels, together with two reports prepared Dr Nielssen.
Each of the psychiatrists obtained a history from Mr Delaney which was supplemented by the documentary material provided to each. That history involved a number of hospitalisations for psychiatric treatment and the prescription of various antidepressant and antipsychotic medications commencing from Mr Delaney’s early twenties, though Mr Delaney reported various symptoms preceding that time. A diagnosis of bipolar disorder was suspected at the time of an admission to Cumberland Hospital in 2013 and a diagnosis of schizophrenia recorded in relation to Mr Delaney’s admission at Armadale Hospital in Western Australia in 2018. Mr Delaney reported to both psychiatrists that he had been taking reduced or no medication in the period leading up to the offence, following his relocation from Western Australia, where he had been residing, to New South Wales in 2019.
Dr Samuels interviewed Mr Delaney on 24 February 2022 via AVL and provided his first report the same day. He had been provided with other materials including the Crown Case Statement, Justice Health Records and records from Cumberland Hospital.
Mr Delaney reported a history of drug use. Since his return to New South Wales, this included regular marijuana use and the use of ice around once every two months. He thought he may have used ice a week or two before the offence.
When asked about what occurred on the day of the offence, Mr Delaney said he was only able to recall some of what occurred. He said he had been at home smoking marijuana and believed there was another person in his home. When Mr Delaney tried to get the person to leave, the person got angry and “changed from a normal person to ‘a tall person like a demon’”. Mr Delaney proceeded to grab some tools that had been behind the couch and struck the “demon” with them. He then reported that he “came to” at a hotel, where he was experiencing paranoia, including a belief he was being followed by Freemasons, at which time he took himself to Cumberland Hospital.
Dr Samuels opined that Mr Delaney’s most likely diagnosis was a schizoaffective disorder. He expressed that Mr Delaney appeared to meet the diagnostic criteria for schizophrenia and for substance misuse disorder, predominately involving marijuana, though noted Mr Delaney’s intermittent use of crystal methamphetamine.
With respect to the requirements of the defence of mental health impairment under s 28(1) of the Act, Dr Samuels expressed the opinion that Mr Delaney may not have known the nature and quality of his act and did not know his act was wrong in the relevant sense.
As to the cause of this condition, while Dr Samuels acknowledged it was possible that Mr Delaney had experienced a relapse of his underlying mental illness brought on by his drug use in the period preceding the killing, he ultimately favoured the view that the accused’s impairment at the time of the killing was the result of the temporary effect of ingesting a substance, being marijuana, and, likely, crystal methamphetamine. Satisfaction that the impairment was “caused solely by … the temporary effect of ingesting a substance” would have the result that Mr Delaney was not suffering from a “mental health impairment” and the special verdict would not be available to him. In support of his conclusion Dr Samuels noted Mr Delaney had not appeared to be “unwell” prior to the offence, nor had those with whom he had contact noted “significantly unusual behaviour or abnormal thinking patterns” in the short period following the offence.
Dr Samuels was engaged by the Crown to prepare a subsequent report for the purposes of the appeal proceedings. He conducted a further interview with Mr Delaney via AVL on 10 March 2025 and again provided his report the same day. Among other material, Dr Samuels was provided with the report of Dr Nielssen dated 22 February 2024. In his further report, Dr Samuels noted that Mr Delaney had provided inconsistent accounts with respect to both his historic substance abuse, his substance use around the time of the offence and his recollection and account of the offence itself. These inconsistencies had been summarised by the Crown in its letter of instruction.
Dr Samuels largely reiterated the opinions expressed in his first report. He maintained the view that at the time of the offence, Mr Delaney may not have known the nature or quality of his act and did not know that the act was wrong. As a result, the only issue with respect to the availability of the special verdict remained whether the “impairment [was] caused solely by … the temporary effect of ingesting a substance”. Dr Samuels acknowledged the lack of clarity as to Mr Delaney’s drug use leading up to the offence. In line with his initial opinion, Dr Samuels acknowledged the possibility that Mr Delaney’s “underlying vulnerability to psychosis precipitated brief psychotic symptoms after ingesting substances” but again preferred the view that the offence occurred as a result of the temporary effect of ingesting substances. However, Dr Samuels also clarified that as he could not exclude Mr Delaney’s underlying psychotic illness as a possible causal factor, he was unable to say the offence was “solely” caused by the temporary effects of substance use.
In conference, and in his subsequent email, Dr Samuels further clarified his opinion with respect to the relationship between Mr Delaney’s drug use and his mental state at the time of the killing. Dr Samuels’ stressed that, in his opinion, absent the ingestion of drugs, Mr Delaney would not have entered the psychosis that led to the killing. The Court of Criminal Appeal, however, has made clear that establishing that the impairment would not have occurred but for the ingestion of a substance is not the same thing as establishing the impairment was caused solely by the ingestion of a substance: Delaney v R at [66]. In this regard Dr Samuels’ opinion, reflected in the conference notes and the subsequent email, is that Mr Delaney has an underlying vulnerability which had the result that the ingestion of a substance triggered his psychosis. In other words, the psychosis resulted from a combination of Mr Delaney’s pre-existing vulnerability and the ingestion of a drug. Dr Samuels’ opinion, ultimately, is that the impairment was not solely caused by the ingestion of a substance.
Dr Nielssen interviewed Mr Delaney on 14 February 2024 via AVL and provided his report on 22 February 2024. Dr Nielssen was also provided with substantial additional material, including the Crown Sentence Summary, hospital admission and mental health care records, Justice Health Records and the initial report of Dr Samuels.
With respect to his drug use leading up to the offence, Mr Delaney told Dr Nielssen that he had been using marijuana since the age of 14 or 15 and had been using methamphetamine “on and off” in the year and half leading up to the offence. Mr Delaney reported that it was “more than likely” he smoked cannabis on the day of the offence as he was a daily user at that time but denied smoking ice that day as he did not have or use it at home.
Mr Delaney’s account to Dr Nielssen, largely similar to that provided to Dr Samuels, described a hallucination in which he believed he was being attacked by a demon.
Dr Nielssen diagnosed Mr Delaney with schizophrenia on the basis of his reports of hallucinations, delusional beliefs, the information provided in various medical records and aspects of his presentation. Dr Nielssen also diagnosed Mr Delaney with substance use disorder.
Dr Nielssen opined that, at the time of the offence, Mr Delaney “was affected by an acute exacerbation of his underlying schizophrenic illness”. Dr Nielssen further opined that Mr Delaney’s condition was neither temporary nor solely due to the effects of intoxication, given he was a chronic cannabis user and reported that he had only ingested his “usual amount of cannabis that day”.
Dr Nielssen is of the view that Mr Delaney’s impairment meant that at the time of the offence Mr Delaney did not know the nature and quality of his act and did not know that his act was wrong.
Dr Nielssen was engaged by the defence to provide a subsequent report. He did not interview Mr Delaney again but was provided with additional materials including the report of Dr Samuels dated 10 March 2025. In his further report, dated 15 April 2025, Dr Nielssen simply stated that he “did not find anything in the further information to change the opinion expressed in [his] previous report”.
I have had regard to all material placed before the Court.
There is no issue that the accused is responsible for the physical acts which caused his sister’s death.
The evidence of both of the psychiatric experts has been consistently to the effect that, whether or not Mr Delaney knew the nature or quality of his act, he did not, at the time, know that the act was wrong in the sense that he could reason with a moderate degree of composure about whether the act as perceived by reasonable people was wrong. The only matter that has been in issue with respect to the availability of the special verdict is whether Mr Delaney was suffering from a mental health impairment that had the effect that he did not know his act was wrong, such that the defence of mental health impairment as set out in s 28(1) of the Act is available.
The opinions of Drs Samuels and Nielssen are materially consistent in that they establish that Mr Delaney, at the time the killing was carried out, was suffering from schizophrenia, or at least a schizoaffective disorder, each of which is capable of being classified as a mental health impairment within s 4 of the Act. The issue until recently has been the negativing provision in s 4(3), which excludes from the definition of mental health impairment an impairment caused by the temporary effect of ingesting a substance, or substance use disorder. The former operates only, however, when the impairment is caused solely by the temporary effect of the ingestion of a substance. Dr Nielssen was clear in his opinion that, at the time of the offence, Mr Delaney was “affected by an acute exacerbation of his underlying schizophrenic illness” with the result that “his condition was not solely due to the effect of intoxication”. Dr Samuels’ opinion with respect to this matter has been less fixed. Ultimately, however, Dr Samuels has also concluded that Mr Delaney’s condition was not solely due to the effect of intoxication. I would not reject the opinions of these appropriately qualified experts unless there was some proper foundation for me to do so. There is no such foundation.
[The victim impact statements were read in Court. His Honour addressed each of the authors and acknowledged the deep distress and grief suffered by Ms Delaney’s family members.]
I formally acknowledge the receipt of the victim impact statements and repeat what I have said in that regard, that they are received and acknowledged pursuant to s 30L(2) of the Crimes (Sentencing Procedure) Act 1999 (NSW). Those statements will be provided to the Mental Health Tribunal pursuant to the orders that I make.
(1) On the charge that the accused, between 2 June 2020 and 9 June 2020, at Cambridge Park in the State of New South Wales, did murder Gabriella Delaney, I return a special verdict of act proven but not criminally responsible.
(2) Pursuant to s 33(1)(b) of the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW) (the Act), the accused is to be detained in a correctional facility, or at such other place as may be determined from time to time by the Mental Health Review Tribunal until released by due process of law.
(3) Pursuant to s 34 of the Act, the accused is referred to the Mental Health Review Tribunal.
(4) Pursuant to s 30N(4) of the Crimes (Sentencing Procedure) Act 1999 (NSW), the victim impact statements of Rebekah Delaney, Jayleb Delaney, Kayla Tompkins and Daniel Delaney are to be provided to the Mental Health Review Tribunal.
(5) The Registrar is to notify the Mental Health Review Tribunal, as soon as it is practicable, of the making of these orders and is to provide to the Tribunal the following documentation:
(a) A copy of my reasons for verdict and the making of these orders;
(b) A copy of the exhibits tendered in these proceedings, including the agreed facts and the reports of Dr Anthony Samuels and Dr Olav Nielssen.
(6) The Registrar is to notify the Justice Health and Forensic Mental Health Network, as soon as is practicable, of the making of these orders and is to provide to the Justice Health and Forensic Mental Health Network the following documentation:
(a) A copy of my reasons for verdict and the making of these orders;
(b) A copy of the exhibits tendered in these proceedings, including the agreed facts and the reports of Dr Anthony Samuels and Dr Olav Nielssen.
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R
Delaney