THE STATE OF WESTERN AUSTRALIA -v- MOUSSA [2026] WASC 33 (16 February 2026)

(1) A person is not criminally responsible for an act or omission on account of mental impairment if at the time of doing the act or making the omission he is in such a state of mental impairment as to deprive him of capacity to understand what he is doing, or of capacity to control his actions, or of capacity to know that he ought not to do the act or make the omission.

(2) A person whose mind, at the time of his doing or omitting to do an act, is affected by delusions on some specific matter or matters, but who is not otherwise entitled to the benefit of subsection (1), is criminally responsible for the act or omission to the same extent as if the real state of things had been such as he was induced by the delusions to believe to exist.

1. The applicant anticipates that aside from certain limited evidence,[2] the only other evidence to be called will be expert evidence from a consultant psychiatrist, Dr Adam Brett.[3] A summary of Dr Brett's evidence and reports appears in the ASMF at [75] and the applicant adopts those opinions.[4] As I understand it, the State does not propose to call any further expert evidence.
2. Section 118 of the Criminal Procedure Act relevantly provides as follows:
   1. Trial by judge alone without jury may be ordered

(1) If an accused is committed on a charge to a superior court or indicted in a superior court on a charge, the prosecutor or the accused may apply to the court for an order that the trial of the charge be by a judge alone without a jury.

(2) Any such application must be made before the identity of the trial judge is known to the parties.

(3) On such an application, the court may inform itself in any way it thinks fit.

(4) On such an application the court may make the order if it considers it is in the interests of justice to do so but, on an application by the prosecutor, must not do so unless the accused consents.

(5) Without limiting subsection (4), the court may make the order if it considers -

(a) that the trial, due to its complexity or length or both, is likely to be unreasonably burdensome to a jury; or

(b) that it is likely that acts that may constitute an offence under The Criminal Code section 123 would be committed in respect of a member of a jury.

(6) Without limiting subsection (4), the court may refuse to make the order if it considers the trial will involve a factual issue that requires the application of objective community standards such as an issue of reasonableness, negligence, indecency, obscenity or dangerousness.

(7) If an accused is charged with 2 or more charges that are to be tried together, the court must not make such an order in respect of one of the charges unless the court also makes such an order in respect of each other charge.

(8) If 2 or more accused are to be tried together, the court must not make such an order in respect of one of the accused unless the court also makes such an order in respect of each other accused.

(9) If such an order is made, the court cannot cancel the order after the identity of the trial judge is known to the parties.

1. The applicant's solicitor deposes that neither she nor the applicant are aware of the identity of the trial judge.[5]
2. Both the applicant and the State submit that because there is likely to be no dispute as to the material facts, it is most unlikely that there will be a factual issue at trial that, within the language of s 118(6) of the Criminal Procedure Act:

... requires the application of objective community standards.

1. I accept that common submission.
2. The general principles to be applied were common between the parties. The applicant set out in his submissions principles derived from Steele v The State of Western Australia [2018] WASCA 133 which adopted principles identified in LFG v The State of Western Australia [2015] WASCA 88; (2015) 48 WAR 178. From the applicant's submissions[6] I have extracted the following:

...

(2) The court's power to make an order for trial by a judge alone will not be enlivened unless the court is affirmatively satisfied that, in the particular case, it is in the interests of justice to do so.

(3) The phrase 'in the interests of justice' has a broad connotation, which includes not only the interests of the accused but also the public interest. The public interest in this context includes the proper functioning, and the protection of the integrity, of the criminal justice system is administered by the courts.

(4) It is in the interests of the accused, and also in the public interest, that the accused receive a fair trial according to law. This is a fundamental (but not the only) issue with which section 118 is concerned. It will be 'in the interests of justice' to order a trial by judge alone if that is necessary to ensure the accused receives a fair trial according to law. That will be necessary if there is a real or substantial (as distinct from a remote) doubt as to whether, in the particular case, the accused will receive a fair trial according to law by or before a jury.

(5) It is not possible, generally or in the abstract, to state exhaustively the factors which will be relevant in determining, in a particular case or in a particular kind of case, whether it is 'in the interests of justice' to order that there be a trial by a judge alone.

(6) The phrase 'in the interests of justice', in section 118, contemplates the analysis and weighing of a group of factors. The specific factors which are relevant, and the weight to be given to each of those factors, will depend on the matters in issue in a specific application under section 118(1). They will vary from case to case and must be determined on a case-by-case basis. The relevant factors in each case wil be those which bear upon why it is or is not in the interests of justice, in the particular case, to order trial by judge alone. No one factor will necessarily be paramount or superior to any other factor. Each must be given its appropriate weight in light of the particular facts and circumstances.

...

(8) It may be in the interests of justice to order a trial by a judge alone instead of a trial by or before a jury if, for example, there is a real and substantial (as distinct from remote) risk that:

(c) The jury may have difficulty in properly understanding intricate and disputed expert evidence to be adduced at the trial or in properly applying difficult legal principles in the context of complicated questions of fact.

1. It is common ground that it is unlikely that there will be any factual dispute at the trial.
2. Consistently with the principles set out in [17] above, it is common ground that it will be in the interests of justice to order a trial by judge alone if that is necessary to ensure that the accused receives a fair trial according to law.
3. Further, the applicant submitted that:
   1. In the circumstances of this case, the application of section 27 of the Code requires an understanding of matters of some factual complexity, including:
      1. schizophrenia;
      2. delusional beliefs;
      3. the nature of psychosis;
      4. the development, context and factors contributing to a psychotic episode;
      5. the duration of a psychotic episode; and
      6. how a person can appear to be functioning normally during a psychotic episode.
   2. A jury may struggle with the matters noted at 15. above, particularly 15.e. and 15.f.
   3. Accordingly, it is respectfully submitted there is a real and substantial doubt the Accused will be afforded a fair trial according to law if a trial by jury proceeds and therefore it is in the interests of justice the Accused be tried before a judge alone.
4. Counsel for the applicant expanded particularly on [15(e) and (f)] in the hearing before me. The submission, which I accept, was that a jury may have difficulty in understanding and or accepting the expert evidence going to these aspects.
5. In those circumstances I also accept the submission that those difficulties raise a real and substantial doubt that the application would receive a fair trial before a jury.
6. Additionally, counsel for the applicant submitted that a judge alone trial would shorten the length of trial and result in written reasons where the sole issue was to be determined by reference to expert evidence. In the circumstances of this case, I have not needed to consider or determine those submissions further.
7. On the authorities it is plain that trial by judge alone has not uncommonly been ordered where the issue for determination of the trial is the mental capacity of the accused under s 27 of the Criminal Code, especially where there is little dispute as to the facts: see, for example, TVM v The State of Western Australia [2007] WASC 299 [6] (McKechnie J) and The State of Western Australia v Dent [2023] WASC 69 [28] ‑ [30] (McGrath J).
8. I accept, however, the observations of McGrath J that it is not 'axiomatic that a trial in which the insanity defence is to be determined will be conducted by a judge alone'.[7]
9. The State helpfully identified, by way of example, at least 10 cases since 2017 where such an application has been granted on the basis that the only issue at trial is whether the accused was suffering from a mental impairment at the time of the alleged offending.[8]
10. The State submitted, by reference to Hone v The State of Western Australia [2007] WASCA 283 [7] (Steytler P) and [18] (Miller JA), that the interests of justice dictate that, in this case, the issue of the application of s 27 of the Criminal Code be decided by judge alone.[9] These observations were directed to the potential difficulties for a jury to determine the relevant matter or matters under s 27 of the Criminal Code by reference to the psychiatric evidence.

1. I accept that in this case there is likely to be one issue to be determined, being the applicability of s 27 of the Criminal Code. As seen, I also broadly accept the submissions of the applicant as to the concerns that the applicant may not be afforded a fair trial if the matters were to proceed to a trial by jury.
2. Further, it does not appear that there will be any factual issue that requires the application of objective community standards such as may engage s 118(6) of the Criminal Procedure Act.
3. I also consider it of significance that the State, also, submits that it is in the interests of justice that the trial be by judge alone.
4. I have concluded that it is in the interests of justice that I make the order sought by the applicant.

I certify that the preceding paragraph(s) comprise the reasons for decision of the Supreme Court of Western Australia.

1. At the time of the offending, the accused was a 31‑year‑old male, 172cm in height, and of medium build.
2. The victims are his father, a 72-year-old male, 168cm in height, medium build (deceased, Nadi Moussa), and the deceased's wife Theresa Awad Soliman Salama (the accused's stepmother), then a 52-year-old female of medium build (sustained grievous bodily harm).
3. The victims were married in 2014 (Salama was the deceased's second wife). They had a child, Angela, together who was 6 years old at the time of the assaults.

[Paragraphs [4] - [19] recount the applicant's mental health history which includes that through January 2025 the applicant communicated homicidal thoughts and his belief that he had been abused in his childhood by his father].

1. On or about 27 January 2025, the accused formed the intention to kill his father due to believing he was responsible for sexually offending against him as a child.
2. The accused drove his vehicle, a 2010 Mercedes E63 with a WA registration of 1HLJ367, from his home address of unit 4, 49 Strathpine Road, Bald Hills, Queensland, to his father's home address of 62 Elsbury Approach, Clarkson, Western Australia. He was armed with a large Japanese kitchen knife.

1. About 2:40am on Friday 31 January 2025, the accused arrived in Clarkson. He drove to a location within walking distance of 62 Elsbury Approach (the home address of his father). The accused parked his vehicle nearby his father's house as he did not want to alert his family or their neighbours to his presence.
2. The accused walked to 62 Elsbury Approach holding the knife, intending to wake his father and kill him. The accused walking past holding a knife is captured on the doorbell footage from next door.
3. When the accused arrived, he says in his electronic record of interview (EROI) that he found the screen door shut but not locked and the front door to the house ajar. The accused entered the house and found that no one was present at the address. He decided to wait at the house until his father returned home.
4. He called his brother Andrew Moussa but he did not answer.
5. At 3: 18am the accused messaged his friend Lawrence Samardali on Whatsapp saying that his family have gone into hiding because he came home, the door is unlocked and the house is pristine. There is further talk by him about the family drugging him and the government being in on it. Later on, and throughout the day, there is further talk from the accused about him again accusing his dad, family and the government of drugging him whilst a child. The accused also says he is, 'Ready to kill all who enter ... especially small children.' He talks about thinking that the cops took his family into protection so that he does not kill them. He talks about 7 months ago the memories started coming back, like 'leaks' and then there was a 'flood around December'.

1. On Saturday 1 February 2025 the accused parked his car in the garage and contacted his brother, Andrew Moussa, to find out where his father was. His brother informed him that his father, his step-mother, and their six-year-old daughter (the accused's half‑sister) would all be returning from a family holiday in Thailand on Wednesday 5 February 2025. Andrew Moussa was unaware that the accused was at his fathers' address.
2. The accused remained at the house, waiting for their return. He did not go out as he did not want to alert anyone to his presence at the house.
3. There is a Whatsapp message where Lawrence Samardali asks why the accused did not stop and sleep on his drive over to which the accused replies, at 12:27 'Adrenaline' followed by 'On my way to ki ... I mean see my father.' that he was there. The accused further talks about the researchers saying that they would get into trouble if 'they' killed his father but he wouldn't. The accused says, 'you see. They made me deal with my dad.' The accused later says that his brother Andrew contacted him and informed him that his dad and family were in Thailand and return Wednesday. He says, 'Feb 5th ... which is also my deadline.'

1. February 2025 the accused again had a telephone consult with his treating psychologist, Dr Bennett. The clinical notes state 'is in Perth at present. Has some things to do with the police there in person. Staying in his father's house as his younger brother had told him that his father is in Thailand. Has spoken with a lawyer in WA. Recalling more memories of past abuse. Denies homicidal or suicidal intent - says he will do this through the police. He had hit 2 kangaroos on the way over to Perth. Isn't taking dexamphetamine or cannabinoids - says he stopped this since Dr Batts has asked him to stop'.
2. At 10:12 pm the accused sent a text message to Dr Bennett saying, 'God help me Dr Bennett'.

1. On 4 February 2024 at 5:15am the deceased's youngest son Andrew Moussa picked up the deceased, Salama and their daughter Angela from the airport. Andrew Moussa drove them to his house in Clarkson (around 5:45am to 6am) and the then picked up their car. The deceased drove back to his own address (62 Elsbury Approach, Clarkson), approximately 6:00am on Tuesday 4 February 2025.
2. The accused woke to hear Theresa Salama and her six‑year‑old daughter Angela talking in the kitchen area of the house and got up to see them. They were not expecting the accused to be there. They opened the garage door and saw the accused's car parked in the garage. Everything was initially cordial and normal.
3. The accused stated that he had come to stay with them for about a week, not mentioning his intentions to kill his father. The accused said something like he wanted Angela to come with him. He took the six-year-old daughter through the garage outside to the front of the house, and told her that he wished to speak with his father and her mother on their own.
4. Angela did not want to wait outside but he closed the garage door to prevent her from getting into the house.
5. The accused returned to the kitchen area, holding a knife. Salama didn't think much of it as she thought it might be to open the gifts that he had brought with him. The accused put the knife on the kitchen bench and Salama moved the knife a little. Salama noticed that Angela was not there and that the accused's face was angry when he came back.
6. The accused picked up the knife and pointed it to the deceased. The accused said 'I remember when I was young. I remember things from when I was young. I never forget anything. I want to kill'. The accused made a motion with the knife as if to cut his own neck. The accused pointed the knife at the deceased and said 'You two sit down here. I want to kill you both. Sit down together. I remember when I was young. I am going to kill you both'.
7. Salama went to the accused and said, 'I was not there when you were young. What happened?'. The accused did not answer but said, 'sit here and I will call the police.' The deceased was also asking the accused to relax.
8. They both tried to convince the accused to drop the knife. The accused refused, so the deceased and Theresa Salama both tried to physically remove the knife from him by holding the hand that the knife was held in. During this struggle, the accused pushed his father and Salama, resulting in his father hitting the edge of the pantry. Salama and Nadi Moussa held onto the accused's hand with the knife in it. At this point 6-year-old Angela was ringing the doorbell, and so the deceased walked from the living area down the corridor to the front door. Nadi Moussa opened the front door and Angela was standing outside. The accused told Nadi Moussa to 'go back'. Nadi Moussa went outside with Angela towards the mailbox.
9. Theresa Salama was still holding the accused's hand with the knife - and the knife cut her as she and the accused moved outside.
10. Salama told Angela to run. At that stage the deceased was near the letterbox. Salama could see the accused waving the knife around. Salama saw Angela run to the end of the road. The accused broke Salama's grip from the knife.
11. At some point Angela came back and said, 'mum did you get wounded, 1130 but Salama told her to she was ok and to go away.
12. Salama went toward the deceased who was near their car and the deceased told her to call an ambulance. The accused moved around toward the deceased from the other direction and stabbed the accused twice in the back very fast. The deceased fell to the floor.
13. Salama put out her hands to try to protect the deceased and felt the knife cut her hand. She also felt the knife in her arm. She did not feel getting stabbed in the stomach.
14. The accused stabbed the deceased several more times (Salama cannot recall how many). The accused then stepped back and said 'I'm sorry dad.' The accused then stepped forward and stabbed the deceased to the heart. The accused then walked away.

1. Salama sustained a laceration to her right hand, a laceration to her left forearm and a penetration wound to her abdomen (upper left quadrant). In relation to the laceration to her right hand, without medical treatment the injury was of such a nature to cause or likely to cause permanent injury to health. Without medical treatment, a complete transection of one of the neurovascular bundles of the little finger would be expected to result in permanent sensory loss, impaired circulation, and consequent functional limitation of the finger and overall hand function.

1. When the next-door neighbour Jasvinder Kaur Kundi was outside, Angela came up to her and said, 'My brother hurt my dad.' Another neighbour, Filloli Pereda-Mieses, heard Angela say, 'my brother stabbed my dad.'
2. Police were first on the scene and started doing first aid - they conduced CPR for about 9 minutes until paramedics arrived.
3. The accused walked toward Senior Constable (SC) Rixson. The accused held out a mobile phone in front of him and told SC Rixson that the lady on the phone would like to talk to him. SC Rixson saw blood on the accused's hands and asked him if he had a knife on him. The accused said no. SC Rixson handcuffed the accused and brought him to the police van. After being given a caution, the accused told SC Rixson that the knife was inside.
4. They arrested the accused (at 6:30 am) who remained at the scene. The accused was observed to be calm and quiet when put into the back of the police van.
5. SJA paramedics arrived at 6.42 am. SJA officer David Kenny observed multiple stab wounds on the deceased. A decision was made soon after to cease resuscitation due to the deceased's injuries and distance from a major trauma centre. The deceased was certified life extinct at 6:49 am. The report to the coroner from the Forensic Pathologist details a number of sharp force injuries to the victim's wrist, neck, arms and torso (mostly) as well as bruises and abrasions. Of note was an injury to his left lung, heart and liver. The cause of death was multiple penetrating sharp force injuries (stab wounds) to the torso.
6. After assisting with the deceased, SC Rixson went inside the house. He observed no sign of a disturbance. SC Rixson saw a black handled kitchen knife on the kitchen bench with what appeared to be blood on it. A fingerprint was subsequently identified to the accused and a number of blood stains were identified to the deceased.
7. The accused was taken to the Joondalup police station arriving at 8:20 am. He was there for an hour before he was taken to Joondalup Hospital.
8. The accused was assessed in ED by Dr Emma Keegan, the ED Registrar, and a Psychiatry Consultant. She asked the accused, 'do you know why you are here?' to which he replied 'Because I killed my father.' The report from Dr Keegan details the investigations that were made such as CT scans (normal) and blood tests (essentially normal).
9. The accused was deemed fit for custody by the psychiatry team. A full forensic psychiatric assessment was recommended. A blood sample was taken and his bloods were assessed for forensic purposes. He had no alcohol in his system and tested negative for illicit substances.
10. The accused was also reviewed by Consultant Psychiatrist Dr Chacko Varughese as part of his ED presentation. He was deemed fit for custody on the basis that he would be referred to a specialised for this Crohn's disease, get a repeat liver test, was given medication (such as Risperidone) and a full forensic psychiatrist assessment done via the court.
11. At 12:44 the accused returned to the Joondalup Police station. He participated in an EROI later that day.
12. He was then admitted to the Frankland Centre. He was diagnosed with psychosis and treated with antipsychotics.

1. At 6:47pm (same day 4 February 2025) the accused participated in an electronically recorded interview making full admissions to all offences.
2. The accused is very calm and answers all questions. He says that he has a master's degree in science. He stopped working (as a Scientific Salesman) in December. He's not affected by drugs or alcohol. Earlier that day the hospital gave him Risperidone (used in the treatment of Schizophrenia), which made him drowsy, but he's had about 4 hours sleep. He understands the caution.

73.1. I did it. I went there with intent to kill my father. I got there on Friday but the door was open/ajar. I called my brother the next day who said my dad was coming on the 5th.

73.2 I was surprised because they were home early.

73.3 I talked to them and they were surprised I was there. I hugged the little one.

73.4 Everything was fine until they saw a knife on the bench. They were telling the little one not to be scared.

73.5 I locked the little one outside.

73.6 I told my dad I remembered everything. I pulled out the knife.

73.7 My father ran outside. I stabbed my father several times to make sure he was dead. I wanted him to die quickly as I didn't want him to suffer. I told him I was sorry as he lay on the ground, before he died.

73.8 The wife tried to grab the knife but it cut her - it was an accident. The GBH was an accident.

73.9 I then called the police.

73.10 I left Queensland on 27th January. I drove.

73.11 The knife was a Japanese knife that he's had a while.

73.12 Someone told me to kill my father. My eyes were closed at the time. I speak to those researchers (an actual person when he was 15 years old) once or twice a year. They told me it was his home if I did it. In my mind it was the only way to end the study. The drugs make him see the researchers. He had a colonoscopy in August and another on the 27th at 31st at Princess Alexander Hospital.

73.13 He talks about the abuse of his father - locking him in a room for hours and days at a time. His dad was involved in a molestation syndicate where older men would come, drug him, and molest him. The sexual abuse stopped at around 8 or 9, but the neglect continued until he moved out of home when he was 18 or 19.

73.14 He has been seeing a psychiatrist since 2023 for ADHD.

73.15 Police ask why he didn't seek medical help/steps to stop himself killing his dad. He said that the entirety of it was what he was thinking, did know for a fact that his dad had abused him, plus other weird experiences.

73.16 He is shown CCTV from the neighbours' doorbell and agrees that's it's him. 'Who else walks around with a massive knife?'

1. 6-year-old Angela Moussa participated in a CWI the same day of the offending (04/02/2025) at 12:03pm, only a few hours after the death of her father. She said the following:

- We were back from my holiday. My other big brother Andrew drove us home. We saw someone break in (we saw shoes, cans and a straw) and saw my brother. I hugged him. He said he had lollies for me outside in his car (in the garage). There were no lollies, he was lying. He locked me outside. He said, 'stay outside' but I said that it's cold.

- I saw mum get stabbed (twice) inside, I heard my mum shouting 'ow, ow, ow.'

- But clarified she didn't see her mum get stabbed, but just heard. She was still outside at this point. I was scared and sat down.

- They came outside. I saw mum and dad running and David come outside. Mum was standing on this tall thing, like a rock that was big and square - mail box. I saw dad get stabbed outside first, then mum. Mum and dad were saying 'stop David, stop.'

- David had a knife and was stabbing my mum and dad with the knife [showed how big the knife was with her hands]. I was on the street. They were at the front yard. He stabbed my dad one time, and my mum one time.

- I seen my brother stab the knife in my dads.

- I shouted for help, everyone came out and called 000. Then the police and ambulance came. She went to the next door neighbours and they drove me here [to interview].

Consultant Psychiatrist Dr Adam Brett

1. Consultant Psychiatrist Dr Adam Brett has provided two reports. In summary, Dr Brett states:

75.1 The accused has been diagnosed with Schizophrenia and ADHD. He was suffering Schizophrenia at the time of the offending.

75.2 The accused developed a psychosis some time before the offences. The accused was acutely unwell at the time of the offences.

75.3 The accused developed a psychotic episode within the context of prescribed dexamphetamine and medicinal marijuana (although the accused had stopped taking these prior to the offending). The accused had been under a treating psychiatrist in Queensland who had warned him of the potential for psychosis from this combination. His psychiatrist had diagnosed him with psychosis before he travelled to Western Australia. The psychiatrist had told the accused to stop those medications and commenced him on the antipsychotic, risperidone. The psychiatrist had referred the accused to a local mental health service in Western Australia.

75.4 The combination of the medication the accused had been taking and the significant stress he was under appear to be significant factors in his development of psychosis.

75.5 The accused's psychosis involved delusional beliefs about his father, whom he believed had abused him throughout his life. He believed that he had no choice but to kill his father, which he believed would end the research and his suffering. The planning was based on his delusional beliefs.

75.6 The accused's mental impairment did not deprive him of the capacity to know what he was doing. He was aware that he was killing his father, who he believed was instrumental in his suffering.

75.7 The accused's mental impairment did not deprive him of the capacity to control his actions. He had planned the offence, which he did for psychotic reasons.

75.8 The accused's mental impairment deprived him of the capacity to know that he ought not do the act. He believed that his life was in danger. He believed that if he did not kill his father, his father would kill him. He believed that what he was doing was morally right. He believed that the government would give him a new identity and he would not go to prison.

[2] Fedele affidavit [10]: The applicant anticipates the State case will be limited to body-worn camera and CCTV footage, the electronically recorded interview given by the applicant and certain medical reports.

[4] Applicant's submissions filed 27 November 2025 (Applicant's submissions) [12].

[7] The State of Western Australia v Dent [2023] WASC 69 [31].

[8] State's submissions filed 10 December 2025 (State's submissions) [18] and footnote 6.

[9] State's submissions [22] - [23].