The State of Western Australia v Brearley - [2025] WASC 308

JURISDICTION : SUPREME COURT OF WESTERN AUSTRALIA
IN CRIMINAL

CITATION:   THE STATE OF WESTERN AUSTRALIA -v- BREARLEY [2025] WASC 308
CORAM:   QUINLAN CJ
HEARD:   12 & 13 FEBRUARY 2025
DELIVERED          :   17 FEBRUARY 2025
PUBLISHED           :   5 AUGUST 2025
FILE NO:   INS 14 of 2023
BETWEEN:   THE STATE OF WESTERN AUSTRALIA
Prosecution
AND
JACK STEVEN JAMES BREARLEY
First Accused
BRODIE LEE PALMER
Second Accused
MITCHELL COLIN FORTH
Third Accused
ALEESHA LOUISE GILMORE
Fourth Accused
ETHAN ROBERT MACKENZIE
Fifth Accused

Catchwords:

Criminal law – Admissibility of police interview with accused – Whether accused was a suspect – Whether evidence should be excluded in the exercise of the unfairness discretion – Whether evidence should be excluded in the exercise of the public policy discretion

Legislation:

Nil

Result:

Application to exclude interview refused

Category: B

Representation:

Counsel:

Prosecution	:	B F Stanwix SC with T L S Tan
First Accused	:	S Watters with B M Morrow
Second Accused	:	C P Porter with K J Pearson
Third Accused	:	A G Elliott with A F Kraus
Fourth Accused	:	S D Freitag SC with C J Hampson
Fifth Accused	:	D C Jones with J C Solliss

Solicitors:

Prosecution	:	Director of Public Prosecutions (WA)
First Accused	:	Legal Aid WA
Second Accused	:	Legal Aid WA
Third Accused	:	Legal Aid WA
Fourth Accused	:	Legal Aid WA
Fifth Accused	:	Legal Aid WA

Cases referred to in decision:

Bunning v Cross [1978] HCA 22; (1978) 141 CLR 54
Holmes v The Queen, Unreported, Court of Criminal Appeal, WA Library No 970457, 12 September 1997
Holmes v The State of Western Australia [2023] WASCA 26
The State of Western Australia v Gibson [2014] WASC 240; (2014) 243 A Crim R 68
Undalghumen v The State of Western Australia [2024] WASC 468
Webb v The Queen (1994) 13 WAR 257

QUINLAN CJ:

Introduction and overview

The accused, Jack Steven James Brearley (Mr Brearley), Brodie Lee Palmer (Mr Palmer), Mitchell Colin Forth (Mr Forth) and Aleesha Louise Gilmore (Ms Gilmore), were charged on indictment, inter alia, that on 23 October 2022, at Middle Swan, they murdered Cassius Charles Turvey.
The State case was that, on 13 October 2022, Mr Brearley struck the blow that caused the death of Cassius Turvey. The State case against Mr Forth was that he did an act to aid, or aided, Mr Brearley (with the required intention to do so), pursuant to s 7(b) or (c) of the Criminal Code (WA), or alternatively that each of Mr Brearley, Mr Palmer, Mr Forth, and Ms Gilmore formed a common intention with the other accused to prosecute an unlawful purpose – namely, as a group of adults, to find and threaten and/or attack with weapons school‑aged children – a probable consequence of which was the commission of the offence of murder, pursuant to s 8 of the Criminal Code.
As part of its case, the State proposed to lead, inter alia, evidence of an interview with the accused Mitchell Colin Forth conducted at his home on 22 October 2022 (22 October interview). The 22 October interview was one of three substantive interviews proposed to be adduced by the State in relation to its case against Mr Forth; the other two having occurred on 29 October 2022 and 19 January 2023.
Mr Forth objected to the admission of the 22 October interview. Initially the objection was made on two broad bases: first, that it was made involuntarily and, in the alternative, that it should be excluded on the basis of the unfairness discretion or on the basis of the public policy discretion (i.e. the Bunning v Cross discretion)[1] recognising the overlapping nature of those two discretions. There was no suggestion of any breach of the Criminal Investigation Act 2006 (WA).[2]
[1] Bunning v Cross [1978] HCA 22; (1978) 141 CLR 54 (Bunning v Cross).
[2] In that regard, while Mr Forth contended that he was a 'suspect' for the purposes of the Criminal Investigation Act 2006 (WA), there was no suggestion that he was an 'arrested suspect'. Section 138 of the Criminal Investigation Act 2006 therefore had no application. In addition, to the extent that Mr Forth was a 'suspect', the admissions in the 22 October interview were contained in an audiovisual recording, such that s 118 of the Criminal Investigation Act 2006 was complied with.
On 12 and 13 February 2025 I conducted a voir dire in relation to the objection to the 22 October interview. In the course of the voir dire, the State called evidence from Detective Senior Constable Darryl Mears, Detective Senior Constable Jonathan Symons and Detective Senior Constable Taylor Evans. Mr Forth also gave evidence in the voir dire.
After the conclusion of the evidence, counsel for Mr Forth did not press the objection based on voluntariness.[3] Counsel did, however, press for the 22 October interview to be excluded on discretionary grounds (both on fairness and public policy grounds).
[3] Ts 915.
I reserved my decision and, on 17 February 2025, I refused the application to exclude the 22 October interview on discretionary grounds and determined that the 22 October interview was admissible (subject to it being edited in accordance with edits ruled upon by me at a directions hearing on 31 January 2025).
While I gave brief reasons as to my essential conclusions at the time, I did not set out all of my reasons for those conclusions (including any findings in relation to the credibility of any of the witnesses who gave evidence in the voir dire). In that regard, I followed the practice recommended in decisions such as Webb v The Queen[4] and Holmes v The Queen[5] of providing full reasons after the conclusion of the trial.
[4] Webb v The Queen (1994) 13 WAR 257, 260 (Malcom CJ), 267 ‑ 271 (Ipp J).
[5] Holmes v The Queen, Unreported, Court of Criminal Appeal, WA Library No 970457, 12 September 1997 (Holmes v The Queen).
Those cases are to the effect that, while it is clear that a judge is required to give reasons for decision in a voir dire, a degree of circumspection may be required while the trial is still ongoing, particularly in relation to credibility findings. As Wallwork J (with whom Pidgeon J agreed) said in Holmes v The Queen:[6]
[F]or a trial Judge, at the commencement of a trial and after the hearing of a voir dire, to give details as to why he has accepted the evidence of police officers and rejected the evidence of an accused person (which in many cases would be in effect to state that the Judge believes that the accused person is telling lies) could immediately raise doubts in the mind of an accused person as to whether that person was getting a fair trial. In my view such a course would be most undesirable. Detailed reasons could always be given after the trial.
[6] Holmes v The Queen, 2 (Wallwork J).
Adopting this approach, I now provide more detailed reasons.
Before turning to the evidence, the relevant legal principles can be briefly summarised.

Legal principles

The general principles in relation to the admission or exclusion of confessional statements were recently summarised by Whitby J in Undalghumen v The State of Western Australia. I gratefully adopt that summary:[7]
[7] Undalghumen v The State of Western Australia [2024] WASC 468 [107] ‑ [111] (Whitby J).
[107]In summary:
(1)it is a fundamental common law requirement that a confessional statement must be voluntary;
(2)it is presumed that a confessional statement is voluntary if there is nothing to suggest that it is involuntary;
(3)if the issue of voluntariness is raised, the State bears the onus of establishing, on the balance of probabilities, that the statement is voluntary;
(4)the requirement that a statement be voluntary means that it must have been made by the confessionalist in the exercise of his or her free choice to speak or remain silent. An accused who speaks while overborne is not speaking voluntarily. A statement made as a result of duress, intimidation, or sustained or undue insistence or pressure is not voluntary. A confessional statement will be excluded from evidence as involuntary if it has been obtained from an accused either by fear of prejudice or hope of advantage, exercised or held out by a person in authority;
(5)if a confessional statement is voluntary, it is prima facie admissible, but it may nevertheless be excluded by the court in the exercise of discretion;
(6)the residual discretion to exclude a voluntary confessional statement is exercisable on one or more of the following bases:
(a)it would be unfair to the accused to admit the statement. The purpose of this discretion is to protect the rights and privileges of an accused;
(b)considerations of public policy make it unacceptable to admit the statement into evidence. The purpose of this discretion is to protect the public interest; and
(c)the statement's prejudicial impact outweighs its probative value. The purpose of this discretion is to guard against a miscarriage of justice;
(7)it is not always possible to treat voluntariness, unfairness, public policy and prejudicial weight of the statement as discrete considerations in deciding whether the discretion to exclude it should be exercised – these are often overlapping considerations; and
(8)an accused who asserts that the court should exercise its discretion to exclude a voluntary confession on one of these bases bears the onus of proving facts that would justify an exercise of the residual discretion in his or her favour.
[108]In assessing whether an accused's will is 'overborne', the test is subjective. In applying the test, regard must be had to the age, background and psychological condition of the accused and the circumstances in which the confession is made. The conduct of police before and during an interview is a relevant factor in determining whether a confession is voluntary. The fact that the police did not consciously seek to overbear the will of the accused does not matter.
[109]When considering the issue of unfairness to the accused, the question is not whether the police acted unfairly or improperly, but whether it would be unfair to the accused to use her confessional statement against her; the primary concern of the unfairness discretion is whether the confession may be unreliable. However, that is not the only concern. There may be unfairness to the accused because the statement might not have been made at all if the interrogation had been properly conducted.
[110]In determining whether considerations of public policy make it unacceptable to admit the statement into evidence, the court must weigh against each other two competing requirements of public policy – those being on the one hand, the public interest in convicting persons who have committed criminal offences and on the other hand, the public interest in protecting persons from unfair and unlawful treatment.
[111]A confessional statement may be excluded where a police officer continues to question the accused after she has stated that she does not wish to answer questions. Once the accused has indicated she wishes to exercise her right to silence, the police should not pressure or cajol the accused into answering questions as this dilutes the effect of the caution given to the accused. Where a person clearly exercises their right to refuse to answer questions, the police should not continue questioning the accused and any confessional statement would generally be ruled inadmissible in the exercise of discretion. (citations omitted)
As noted above, while Mr Forth's objection to the admission of the 22 October interview initially relied upon voluntariness, that objection was not pressed. The issues before me therefore concerned whether the 22 October interview should be excluded on the basis of the unfairness discretion or on the basis of the public policy discretion.
Underpinning the application to exclude the 22 October interview on discretionary grounds was Mr Forth's contention that at the commencement of the interview, the police ought to have cautioned Mr Forth on the basis that he was a suspect. The State contended that Mr Forth was interviewed on that occasion as witness, rather than as a suspect.
In The State of Western Australia v Gibson, Hall J (as his Honour then was), said, in the context of the Criminal Investigation Act 2006 that:[8]
For the purpose of pt 11 of the CIA, in which s 118 is contained, a suspect means a person suspected of having committed an offence, whether or not he or she has been charged with the offence. Suspicion is a state of conjecture or surmise where proof is lacking. Facts which can be the basis of a reasonable suspicion may be insufficient to ground a belief. A suspicion must have some factual basis but it may be merely a positive feeling of actual apprehension or mistrust or a slight opinion without sufficient evidence to establish it: George v Rockett [1990] HCA 26; (1990) 170 CLR 104, 115. In South Australia it has been held that fairness will require a caution if the person's possible involvement in the crime remains under consideration, even though they may not be regarded as a suspect: R v Buetti (1997) 70 SASR 370, 378.
[8] The State of Western Australia v Gibson [2014] WASC 240; (2014) 243 A Crim R 68 (The State of Western Australia v Gibson) [38] (Hall J).
The parties accepted before me that this definition of 'suspect' was relevantly applicable in the present case.
As Hall J made clear in The State of Western Australia v Gibson, the question as to whether a person is a suspect is a question of fact, not some formal act of decision making. In that respect, for the purposes of whether a person should be cautioned, the question is not whether the relevant police officers' subjectively suspected the person of committing an offence but whether, on the available information, they ought reasonably have done so.[9]
[9] The State of Western Australia v Gibson [41], [43] (Hall J).
I turn then to the evidence.

Evidence

As the voluntariness of the 22 October interview was initially in issue, the State called evidence first. In addition to documentary evidence, the State called Detective Mears, Detective Symons and Detective Evans.

Detective Darryl Mears

Detective Mears gave evidence that in October 2022 he was stationed at Midland Detectives and was the investigating officer in relation to the alleged assault against Cassius Turvey (before it became a homicide investigation).
Detective Mears said that he attended Mr Forth's address at around 10.20 pm on 22 October 2022 with Detective Matthew Bethune. He said that Mr Forth's status was as 'a witness', because 'on the basis of the information that I had at the time, I had no reason to think that [Mr Forth] was personally involved in the assault'.[10]
[10] Ts 695.
Detective Mears said that after Mr Forth confirmed that he was prepared to talk to the detectives, he turned on his body worn camera. The recording of the 22 October interview was tendered on the voir dire, as were subsequent interviews conducted with Mr Forth by the Homicide Squad on 29 October 2022 (29 October interview) and 19 January 2023 (19 January interview).
It is clear that at the commencement of the 22 October interview, Mr Forth was advised that he was not under arrest, that he did not have to talk to police, he did not have to say anything and that he could ask the police officers to leave. Mr Forth was not advised that anything that he did say could be given in evidence.
Detective Mears was cross‑examined as to his training in relation to interviews, including his understanding of the circumstances in which a person will be considered a 'suspect'. He confirmed, correctly, that in order to consider a person a suspect 'you don't have to be able to prove that they committed the offence', but needed 'reasonable suspicion'.[11]
[11] Ts 701.
Detective Mears was taken to various information concerning the investigation that was available to him at the time of the 22 October interview, including by reference to the running sheet for the investigation, which was tendered in evidence. That information included statements from witnesses to the effect that they observed a person in 'FIFO wear' at the scene[12] (evidently a reference to Mr Forth) and that Mr Brearley had implicated Mr Forth as having been with him on the day.[13]
[12] Ts 706.
[13] Ts 708.
Detective Mears was shown an email from Detective Senior Constable William McAdoo from the Homicide Squad dated 19 October 2022, which included a number of suggested actions. That email contained the entry:[14]
Suspect
Identify the other passenger and driver of the VOI [Vehicle of Interest]
[14] Exhibit VD7.
Detective Mears said that he had not seen the email before and confirmed that he 'didn't consider [Mr Forth] a suspect'.[15]
[15] Ts 710.
In addition, Detective Mears was taken to a number of witness statements obtained in the course of the investigation, including a statement from one of Cassius Turvey's friends (ND) who described an incident in which ND was assaulted.[16] ND's witness statement included the following:[17]
[16] Ts 711.
[17] Exhibit VD14.
15.Another male got out back passenger side was wearing a fluro green tradie t‑shirt with a collar, work shorts and brown work boots. He looked about mid 20's, medium build, blonde short hair and was white.
16.I saw a tall skinny guy wearing a white shirt and cream coloured shorts get out of the back drivers side. He looked to be in his early 20's, had white skin and spoke with an Australian accent. He was holding a black pole about 30 centimetres long.
17.The pole looked like it had sharp objects on the end, maybe barbed wire.
18.He chased after all my friends who had run off into the bushland to the right.
19.The guy in the fluro shirt ran up to me and I heard him say 'who smashed my car'?
20.By this point, I was left with just [M] and [L] because everyone else ran off and I was left behind with my crutches.
21.I said 'I don't know, I don't know'.
22.The guy in the fluro asked me 'Do you know those boys?'
23.I said 'I don't know'
24.The male in the white shirt came running back towards us from the bushland.
25.I heard one of the other people from the car call the male by the name of 'Jack'.
26.The male (Jack) approached me and hit me across the face with the pole once.
27.He was holding the pole in his right hand.
28.I am unsure if Jack said anything to me before hitting me with the pole.
29.I stumbled back dropping my crutches on the floor. It hurt a lot.
The alleged assault described by ND was the subject of count 4 on the indictment. The reference in the statement to the person in the 'fluro' is evidently a reference to Mr Forth.
Finally, Detective Mears was cross‑examined as to his conduct of the interview and the nature and purpose of the questions that he asked of Mr Forth. While those questions in cross‑examination suggested that some of the questions asked of Mr Forth were designed to elicit evidence against him (which Detective Mears denied), it was not put to Detective Mears that he subjectively had a reasonable suspicion that Mr Forth may have committed an offence.[18] Consistent with that approach, counsel later accepted in the course of submissions that the officers honestly regarded Mr Forth as a witness.[19]

Detective Jonathan Symons

[18] Ts 718 ‑ 719.

[19] Ts 904.

Detective Symons was a member of the Homicide Squad, which assumed carriage of the investigation from Midland Detectives on 23 October 2022 (the day Cassius Turvey died). Detective Symons was the witness manager.
Detective Symons gave evidence that, on 24 October 2022 he was asked to contact Mr Forth as a witness to obtain or clarify his account.[20] He gave evidence as to his contact with Mr Forth, in which he said he was seeking a witness statement. Detective Symons also spoke to a lawyer assisting Mr Forth, after which arrangements were made for Mr Forth to provide a witness statement at the Midland Detectives Office at 4.00 pm on 25 October 2022.
[20] Ts 724.

Detective Symons gave evidence that, prior to meeting with Mr Forth on 25 October 2022, he received a draft witness statement from another child witness (TN), which caused him to discuss with the investigating officers whether Mr Forth should still be regarded as a witness or as a suspect. The outcome of that inquiry was that Mr Forth was still to be treated as a witness, as the information from TN was deemed unreliable by the senior investigating officer.[21]
[21] Ts 726 ‑ 727.
Detective Symons met with Mr Forth on 25 October 2022. He took an account of the events of 13 October 2002 from Mr Forth, from which Detective Symons made handwritten notes. While Detective Symons intended to finalise a witness statement for Mr Forth, on 28 October 2022 a decision was made by the senior investigating officer to reclassify Mr Forth as a suspect. For that reason a witness statement was not finalised, as it would have been 'inappropriate' to do so.[22]
[22] Ts 729.
In cross‑examination Detective Symons confirmed that he was not provided with a transcript of the 22 October interview and did not take it into account in assessing whether Mr Forth should be treated as a witness or as a suspect.[23] Detective Symons was also asked a number of questions in relation to his understanding and practice concerning the conduct of interviews with witnesses and suspects.[24]

Detective Taylor Evans

[23] Ts 731.

[24] Ts 732.

Detective Evans was called by the State and made available for cross‑examination. She gave evidence that on 22 October 2022, during the day, she attended Mr Forth's address to speak to him. She said that she also went to the address to look for Mr Brearley.[25]
[25] Ts 737.
According to her notes, Detective Evans said that when she spoke to Mr Forth, he asked to call his lawyer for advice, which he then did. After that, again according to her notes, Detective Evans said that Mr Forth said 'no comment' and no further questions were asked of him. Detective Evans said that she did not caution Mr Forth at the time because he was not a suspect.[26]

Mitchell Forth

[26] Ts 738.

Mr Forth gave evidence on the voir dire and was cross‑examined.
Mr Forth gave an account of the interaction with Detective Evans on 22 October 2022, which was consistent with the evidence given by Detective Evans.
He then gave an account of the attendance by Detective Mears and Detective Bethune:[27]
Well, later on in the day, yeah, I – I had a – just continued with my normal day. I think me and dad had a few drinks and then we went to bed. Probably about 20 minutes, half an hour from going to bed, we heard a knocking on the door so we – I got up and seen who it was. Dad was – got up at – too, and I opened the door and it was the detectives – one of the detective from last night that give evidence as well. He come to the door and he asked if we knew – if I knew where Jack was. I said I didn't know. He's like, 'Are you willing to give a statement cos we're just going to keep on coming,' well, you know. I said – I looked at Dad and Dad said to me, like, 'Mitch, if you're going to say anything, just tell them the truth. You know. Just – it's – they're not going to give up, you know. Just keep on – just get it over with,' so I was like, 'All right.' So I said, 'Yep, all right. I'll give a statement,' and – and they just said, 'Yeah. Cool. You're just as a witness,' rah, rah, rah, and they said, 'Yep.' Then they turned the body‑worn on. They – I think I started talking about it. They said, 'No. Just wait for us to turn the body‑worn on.'
When you say you think you started talking about it?---Yeah.
Are you talking about the events of 13 October?---Yes. Yes.
Okay. Do you remember what you said about the events on 13 October?---No. It – I would have got a couple of words in and then he said, 'No. Stop. I'll turn the body‑worn on first.'
All right. Yes. And after he turned the body‑worn camera on, did you say some things to them?---Yep. Yep. He cautioned me first, said, 'Look, you're – you're not a suspect. You're just a witness. You don't have to say – you – you don't have to talk to me. You don't have to – you can walk off. You can go inside whenever you want. You can tell me to get off your property if you don't want me here,' and I say, 'Yep. Yep. No problems,' and then I continued with my statement.
[27] Ts 875 ‑ 876.
Mr Forth also gave evidence as to his understanding as to whether he was a witness:[28]
Bearing in mind that earlier that day, you had told the police 'no comment' when they came to talk to you, what was the impact on your thinking that they were telling you on this occasion that you were going to be a witness?---I didn't really believe that I thought I was a witness cos they come to my house so late at night. I was looking at Dad. I was, like, 'What – I think – you know, I don't think I'm really a witness. What's really going on here?' so I was, like, I – I didn't think I was a witness but they said I was a witness so I – I believed them.
And what did you think the impact was of being spoken to as a – a witness rather than as a suspect?---Just to give my – just to give my side of what happened, what I seen. I didn't think it would eventuate to anything.
…
Now, when they were talking to you, the police officers on that evening, did they tell you at any point in time that whatever you said could be used in court?---On the 22nd of - - -
On the 22nd?---Yeah. No. No, they never told me that.
Did the fact that they didn't tell you that it could be used in court operate on your mind in any way?---Yeah. Well, if they had have given me a proper caution, I would have contacted my lawyer and asked my lawyer to be present for the interview but I just thought I was a witness so I didn't see the harm in it.
[28] Ts 876 ‑ 877.
Mr Forth was cross‑examined in relation to his account.
He confirmed, both in relation to the interaction with Detective Evans and the 22 October interview, that he understood that he was not under arrest, that he did not have to talk to the officers and, in relation to Detective Mears, that he was 'free to go inside whenever [he wanted]'. In relation to this last matter Mr Forth qualified his answer, saying that 'he didn't really want to be rude and walk off'.[29]
[29] Ts 881.
Mr Forth was cross‑examined in relation to his evidence that the police said to him 'we're just going to keep on coming':[30]
[30] Ts 883 ‑ 884.
The whole time?---Cos when he first rocked up, I said, 'It's just going to be, "No comment", again', and they said, 'Well, we're just going to keep on coming back'. And that's when my father said, 'If you – you may as well talk to them, Mitch, because they're just going to keep on coming back otherwise'.
Right. Well, Mr Forth, that – that didn't happen, did it?---Well, it did.
That's the first we're hearing of it?---You can call my father to stand if you want - - -Well - - -?--- - - - and he'll testify to it as well.
Well, it was never put to the officer yesterday?---I didn't question the officer myself.
Right. So you're saying that that's what happened: that the police told you they were just going to keep coming back - - -?---Yeah.
- - - until you gave a statement?---No. My father said that to me.
What did the police say?---I said, 'No – it's just going to be, "No comment", again', and they said, 'Well, we're just going to come back again'. And then dad said, 'They're just going to keep on coming back, Mitch, if you – you may as well talk to them. If you're going to talk to them, just tell them the truth'.
So the police said to you, when you said, 'It's just, "No comment"' - - -?---Yeah.
- - - that, 'We're going to come back again'?---Yeah.
And 'we're going to keep coming back'?---They didn't say, 'We're going to keep on coming back'.
Right?---They said, 'Well, we're going to come back again.'
All right. Mr Forth, that's just not true, is it?---It is true.
Mr Forth accepted in cross‑examination that he had lied to police in his interviews with them, particularly in relation to whether he had stolen a pair of crutches during the incident and whether he knew about the presence of poles (a trolley pole being the weapon alleged by the State to have been used on Cassius Turvey and the other boy, ND).[31]
[31] Ts 884.
Some context to this part of the cross‑examination is necessary. It is clear from the three interviews tendered on the voir dire that Mr Forth had lied to police as to his knowledge of trolley poles being used on 13 October 2022. In the 22 October interview, he described Mr Brearley and Mr Palmer as having been armed with knuckledusters, but when asked what else they were carrying he said 'I didn't see'. Mr Forth made no mention of the presence of any trolley pole in that interview.
More significantly, in the 29 October interview (following his arrest on suspicion of murder and under caution), Mr Forth was asked directly about trolley poles and denied seeing any:[32]
[32] Exhibit VD2.
DET SGT SHANAHAN: They're saying – and also up here where this young fellow with the crutches gets pushed over. They're saying that, um, we believe it's Jack has some sort of pole.
FORTH: Yeah, right. I didn't – I didn't see any pole in Jack's hands.
DET SGT SHANAHAN: No?
FORTH: I would've mentioned it.
DET SGT SHANAHAN: Yeah.
FORTH: I would've mentioned it.
DET SGT SHANAHAN: You seem to be - - -
FORTH: You know, like, straight – straight up - - -
DET SGT SHANAHAN: - - - quite open, mate, which is great.
FORTH: - - - straight up mention it. I didn't see a pole.
DET SGT SHANAHAN: It's just there's a lot of kids mentioning this pole.
FORTH: Yeah. I didn't see a pole.
DET SGT SHANAHAN: And also independent people saying pole.
FORTH: Yeah, I didn't see a pole. If I had of seen a pole, I would've mentioned a pole.
DET SGT SHANAHAN: Okay.
FORTH: I've mentioned knuckle busters. I wouldn't – mentioned knives. I would've mentioned a pole.
DET SGT SHANAHAN: Yep. No problems.
FORTH: You know.
DET SGT SHANAHAN: Um, and in particular, a couple of the – the witnesses, not just the – the ones off the bus, but others.
FORTH: Yeah.
DET SGT SHANAHAN: Mention it looks like a shopping trolley handle.
FORTH: All right.
DET SGT SHANAHAN: You know, like a shopping - - -
FORTH: Yeah, I know the shopping trolley poles.
DET SGT SHANAHAN: Yeah?
FORTH: No.
DET SGT SHANAHAN: No?
FORTH: No.
DET SGT SHANAHAN: Have you ever seen Jack, or Brody, or anybody with that sort of set up?
FORTH: No. No.
DET SGT SHANAHAN: No?
FORTH: No. Brody with the knuckle busters, no poles.
In the 19 January interview, when describing Mr Brearley's interaction with some of the other persons on 13 October 2022, Mr Forth initially said that Mr Brearley was 'swinging' and when asked what he was swinging, answered 'his arm'. Later in that interview Mr Forth said that Mr Brearley was 'swinging a pole'. He then went on to describe trolley pole handles being broken off trolleys prior to the incident (which he said was done by Mr Brearley and Mr Palmer). He also said that Mr Brearley and Mr Palmer were armed with a pole each when they exited the car at the time of the incident.[33]
[33] Exhibit VD3.
The other lie referred to by Mr Forth in cross‑examination on the voir dire was that when initially interviewed by police he had denied knowing who had taken crutches from ND, when he ultimately admitted, in the 19 January interview, that it was he (Mr Forth) who stole the crutches.
In cross‑examination on the voir dire, Mr Forth proffered various explanations for these lies. The most often repeated explanation was that he had not realised the 'severity of the situation' (an explanation I will return to). He also said that he 'didn't want them [i.e. Mr Brearley and Mr Palmer] to get in trouble because I didn't want implications to then come back on me and me be known as a snitch'. In that context, Mr Forth also said that Mr Brearley told him to stay clear of Mr Palmer.[34]
[34] Ts 887.
Returning to his reason for participating in the 22 October interview, Mr Forth was asked:[35]
So when you were interviewed by them on your doorstep then, why did you answer questions?---Because my dad told me to.
Okay. All right?---He said, 'If you're going to talk to them, Mitch, you may as well talk to them' - - -
Mm hmm?--- '- - - otherwise they're just going to keep on coming back. If you're going to talk to them, make sure you tell them the truth'.
And did you tell them the truth?---No. I left things out.
Mm hmm?---I didn't lie to them, but I left things out. I suppose that's a lie, yes.
And why did you do that?---Because I didn't want to become a snitch. I didn't want to get my mates in trouble and – I didn't realise the severity of the situation.
[35] Ts 889.
The cross‑examination concluded:[36]
Okay. And the reason that you ultimately decided to answer questions was, you just thought it would look too suspicious if you – if you said, 'No', so - - -?---No, cos I'd already done it once.
Okay. What – what do you mean by that?---I'd already said, 'No comment', like earlier on in the day.
And there was no problem with that?---No. No.
So you could have just done it again?---I could have.
Yes?---But my dad told me to just talk to them.
All right. And so it was just because – because your dad said, 'Talk to them'?---Yeah. I rely on heavily – I live with me old man. It's – it's me and him.
All right?---He's the only one in my life at that point in time, so I relied heavily on what he said to me.
Okay. So the – the only reason you continued talking was because your dad said so?---Yes.
[36] Ts 893 - 894.
In re‑examination Mr Forth was taken to the apparent inconsistency in his explanations for why he had participated in the 22 October interview:[37]
By your answer to a question that had the word 'only' in it, 'The only reason', are you accepting that what the policeman said about you being a witness, and your thought about that consequence had no bearing on your decision?---No, I didn't – I didn't think it'd eventuate to nothing.
And – and why did you think that?---Because they just said I was a witness. I thought that cos I didn't think that I'd done anything wrong. I knew I'd done things wrong, but not to the extent of when they said that, 'A boy's in critical condition on life support'.
So when Mr Stanwix asked you a question that asked whether– whether what your father said was the only reason - - -?---It wasn't the only reason but it impacted heavily on my decision.
[37] Ts 896.

Disposition

As noted above, Mr Forth did not ultimately contend that the 22 October interview was involuntary. That concession was clearly correct. The evidence clearly established that Mr Forth participated in the 22 October interview in the exercise of his free choice to speak or remain silent, and that his will to do so was not overborne. In that context, as I will come to shortly, I reject Mr Forth's evidence insofar as it suggested that he spoke to the officers because of any suggestion on their part (express or implied) that they would 'keep coming back'.
As I have also said, underpinning the application to exclude the interview on discretionary grounds was Mr Forth's contention that at the commencement of the interview, the police ought to have cautioned Mr Forth on the basis that he was a suspect.
I found, in that regard, that Mr Forth was advised that he was not under arrest, that he did not have to talk to police, he did not have to say anything and that he could ask police to leave. It was not in dispute, however, that Mr Forth was not advised that anything that he did say could be given in evidence. He was, therefore, not advised as to the second part of the caution that ought to be given to a suspect.

Was Mr Forth a 'suspect'?

The first issue to address in relation to the application is whether Mr Forth was, or ought to have been treated as, a suspect.
In relation to Detective Mears' own state of mind, I accept his evidence that he did not consider that Mr Forth was a suspect; that is, that Detective Mears did not subjectively form a suspicion that Mr Forth had committed an offence. Counsel for Mr Forth did not suggest otherwise, and, indeed, accepted that this was a case in which 'the officers themselves honestly regarded [Mr Forth] as a witness'.[38] Counsel, rather, described the failure to regard Mr Forth as a suspect as being a 'systemic failure' in the sense that the available material was not adequately brought together and analysed.[39]
[38] Ts 904.
[39] Ts 938 ‑ 939.
In any event, as Hall J made clear in The State of Western Australia v Gibson, the question whether a person is a suspect is an objective question of fact to be determined based on the information available to the officers.
In relation to this issue, I concluded, by the merest of margins, that on balance Mr Forth ought to have been regarded as a suspect on 22 October 2022 and therefore ought to have been the subject of a full caution. That is, in light of the information available to the police, objectively, there was a reasonable suspicion that Mr Forth had committed an offence.
In that regard, the witness statements available to the police as at 22 October 2022 included evidence to the effect that Mr Forth was present with Mr Brearley at the time of the events and was actively involved in the confrontation with the group of children. The statement from ND, for example, described the person fitting Mr Forth's description getting out of the car at the same time as Mr Brearley (who was wielding a pole) and that the person meeting Mr Forth's description actively confronted the group, saying 'who smashed my car'.
While none of that evidence suggested that Mr Forth was the principal offender in relation to any offence, it was nevertheless capable of supporting a reasonable suspicion that Mr Forth was assisting, or was otherwise a party to, any offence committed by the person wielding the pole. Importantly, in that context, such a suspicion need not have arisen in relation to an offence against Cassius Turvey; it could also have included suspected offences against ND, who described being assaulted by 'Jack' in the presence of the other people from the car and following the confrontation with the person in the 'fluro'.
I should observe, in that context, that the approach taken by the officers must be viewed in light of the circumstances then existing at the time of the 22 October interview. At that time, Cassius Turvey was still alive, albeit in a deteriorating state. It is therefore not surprising that, at that point, the focus of the investigating police would have been on obtaining evidence (including witness statements) in relation to the actual alleged assailant, who in this case was Mr Brearley. Naturally, once the investigation became a homicide investigation, that focus broadened to other persons who may have secondary criminal responsibility for the victim's death. This provides some explanation for the approach taken by the officers on 22 October 2022.
Nevertheless, from a purely objective standpoint, in my view, the evidence was sufficient that, at the time of the 22 October interview, the investigating officers ought reasonably have suspected that Mr Forth was a party at least to an offence against ND. He therefore ought to have been provided with a full caution on that day.
Consistent with Mr Forth's submissions, the failure to treat Mr Forth as a suspect (and so give a full caution) was not the result of any deliberate misconduct or impropriety on the part of the officers; their assessment that Mr Forth was a witness was a conclusion honestly held. Indeed, notwithstanding my own assessment, it was, in my view, a conclusion that could reasonably have been reached by the police at the time, particularly given that the natural focus and priority of the investigation was on the assault on Cassius Turvey.

Discretionary considerations

Notwithstanding the omission to provide Mr Forth with a full caution, I was not satisfied that the interview should be excluded on discretionary grounds; either in relation to the fairness discretion or the public policy (or Bunning v Cross) discretion.

Factual findings

In that context, the following factual conclusions are relevant to the exercise of the discretions, bearing in mind that the onus was on Mr Forth to prove facts that would justify an exercise of the residual discretion in his favour.
First, I found that Mr Forth freely chose to speak to the officers on 22 October 2022. He was aware of his right not to speak to the police, and indeed had legal advice to that effect earlier in the day. Mr Forth was accompanied by his father at the time, who encouraged him to speak to the police and to tell them the truth.
I rejected Mr Forth's evidence, in evidence-in-chief, that the officers said words to the that they were 'just going to keep coming' until he gave a statement. I find that the officers said no such thing. In this, and other respects referred to below, Mr Forth was not in my assessment a credible or reliable witness.
As to this first matter, it was not put to Detective Mears in cross‑examination that he said that the officers would 'keep coming' and, in Mr Forth's own cross‑examination, he retreated from his evidence‑in‑chief, stating, rather, that they said 'we're going to come back again'. That second version of the conversation was, in my assessment, also unreliable. As with the initial version it was, in my assessment, evidence tailored by Mr Forth to support of his challenge to the interview. In my assessment it was clear that Mr Forth's evidence as to why he spoke to the police on 22 October 2022 changed on a number of occasions during his evidence, including in re‑examination, in response to what he perceived to be in his interests.
Secondly, I was not satisfied that Mr Forth would have declined to speak to the officers if he had been given a full caution. On the contrary, I find that he would have spoken to the police in any event. While the aspect of the caution that was not given (i.e. that anything he said could be given in evidence) is of course important, in my view, it would not have made a significant difference to Mr Forth's decision to speak to the officers on 22 October 2022. In my assessment, Mr Forth's decision to speak to the officers on 22 October 2022 was deliberate and strategic. That is, Mr Forth chose to give an account to the police which inculpated others (including Mr Brearley and Mr Palmer) while endeavouring to exculpate himself. In that regard, Mr Forth's account was consistent with the account that he gave to police following a full caution given following his arrest on suspicion of murder on 29 October 2022. His account was strategically intended to deflect attention from himself.
In that context, I was not satisfied that Mr Forth thought that because he was giving an account as a witness that what he said could not be used against him. I was positively satisfied to the contrary. Mr Forth knew that he did not have to speak and he knew that the conversation with the police was being audio‑visually recorded. The fact that the account given by Mr Forth omitted details that he considered would be bad for him, in my view supports the conclusion that he was, in so far as he was concerned, careful not say anything that would inculpate him. This supports my conclusion that Mr Forth was conscious that what he did say could be used against him; hence his desire to avoid saying anything that would inculpate him.
I also rejected Mr Forth's various explanations for why he initially lied in both the 22 October interview and 29 October interview. His explanation that he did not realise the 'severity of the situation', (which he repeated approximately 10 times in his evidence) was, in large part, a non sequitur. It was not clear exactly what Mr Forth meant by that expression and, in any event, it did not provide a logical explanation for why he would lie to the police. Indeed, the most serious lie that he told (expressly denying any knowledge of trolley poles) was told at a time when he had been arrested on suspicion of murder and had been given a full caution. The 'severity of the situation', either for Cassius Turvey or for him, could not have been clearer.
Relatedly, I also rejected Mr Forth's explanation that he lied to the police to protect Mr Brearley and Mr Palmer (either out of loyalty or fear). In my assessment, in both the 22 October interview and 29 October interview, considered in their totality, Mr Forth gave an account that expressly inculpated Mr Brearley and Mr Palmer. Far from giving an account that wouldn't 'get my mates in trouble', Mr Forth, from the very outset, gave an account which described Mr Brearley and Mr Palmer having 'knucklebusters and stuff', disappearing into the bush and then reporting that 'it was bad' when they returned from the bush. The account involved Mr Forth clearly inculpating Mr Brearley and Mr Palmer, while seeking to deny his own knowledge of what had occurred (including the presence of the trolley poles, which he ultimately admitted in the 19 January interview).
Thirdly, I was satisfied that, while the substance of his account on the 22 October interview, including the admissions contained within it, was very similar to the account that he gave under caution in the 29 October interview, the 22 October interview, nevertheless, contained additional admissions that were probative of facts in issue.
In particular, Mr Forth's admission as to his observations of Mr Brearley's state of aggression when he and Mr Brearley left the vehicle immediately prior to Cassius Turvey being injured was highly probative of Mr Forth's own state of knowledge at the time. That knowledge was relevant to Mr Forth's state of mind for the purposes of both s 7(b) and s 8 of the Criminal Code in relation to the charge of murder.
In the 22 October interview for example, Mr Forth was asked:[40]
What do you think Jack was thinking?---I don't know. I know he was fucking angry. … I knew he was fucking angry.
…
When you say he was angry, what was he doing to make you think that?---Like, 'Fuck, these cunts think they can [run through my house]. Fucking dogs. Rah, rah, rah.' You know? [indistinct] he was fucking mad.
[40] Exhibit VD1; the transcript of the 22 October interview (exhibit VD8 page 4 ‑ 544) contained a transcription error. I am satisfied the above transcription is accurate.
Moreover, those admissions were, in all of the circumstances, reliable admissions. Indeed, as counsel for Mr Forth accepted in submissions, the admissions that were sought to be relied upon as inculpatory admissions in the 22 October 2022 interview appeared to be 'very reliable'.[41] That is, while there were things that Mr Forth accepted that he left out in the 22 October 2022 interview, the admissions in that interview were very reliable and unaffected by the fact that Mr Forth did not receive a full caution.
[41] Ts 907.
Fourthly, I found that any failure on the part of the police to caution Mr Forth was not the result of any deliberate misconduct or impropriety on the part of the officers, nor did it involve them cutting corners; their assessment that Mr Forth was a witness was a conclusion honestly held. It was a conclusion that continued to be held even by officers of the Homicide Squad when they took over the investigation after Cassius Turvey's death. The fact that the Homicide Squad continued to hold that view, even for a short period of time, in my view reflects the reasonable, albeit mistaken, view taken by the detectives on 22 October 2022, as to Mr Forth's status as a witness.
I turn then to the two discretions.

Fairness discretion

As to the fairness discretion, in light of the facts and circumstances as I found them, I was not satisfied that it would be unfair to admit the 22 October interview against Mr Forth.
As the Court of Appeal said in Holmes v The State of Western Australia:[42]
The focus of the unfairness discretion is on the rights of the accused, whereas the public policy discretion is concerned with matters of public interest. The unfairness discretion does not focus on whether the police acted unfairly, but on whether it would be unfair to the accused to use their confession against them. The prime, but not only, concern of the unfairness discretion is the potential unreliability of the confession. In some cases, there may be unfairness to the accused because the confession might not have been made at all or might have been made in a different form if the interrogation had been conducted properly.
Where the confessional statement is both voluntary and reliable, an accused person bears a high onus to establish that the unfairness discretion should be invoked. (citations omitted)
[42] Holmes v The State of Western Australia [2023] WASCA 26 [203] - [204] (Buss P, Beech & Vaughan JJA).
This final proposition was apposite in the present case. As I found, the 22 October interview was both voluntary and reliable and was probative of facts in issue. In addition, I was not satisfied that Mr Forth might not have been made the admissions at all, or might have made them in a different form, if the 22 October interview had been conducted following a full caution. There was otherwise no other basis for concluding that the admission of the interview would be unfair to Mr Forth.
For these reasons, I refused the application to exercise the fairness discretion.

Public policy discretion

The focus of the public policy or Bunning v Cross discretion is the public interest in the protection of the individual against unfair, improper or unlawful treatment. It involves weighing against each other two competing requirements of public policy: on the one hand, the public interest in convicting persons who have committed criminal offences and on the other hand, the public interest in protecting persons from unfair and unlawful treatment.
I am not satisfied that in the present case there was any serious unfair, improper, or unlawful conduct on the part of the police. In my assessment, rather, there was an honest, but mistaken, assessment by the officers that Mr Forth was a witness. That was a conclusion honestly held by them and, indeed, notwithstanding my own assessment, it was a view that could reasonably have been reached by the police officers at the time.
In my view, this case falls within the category described by Stephen and Aickin JJ in Bunning v Cross to the effect that:[43]
[I]t may be quite inappropriate to treat isolated and merely accidental non‑compliance with statutory safeguards as leading to inadmissibility of the resultant evidence when of their very nature they involve no overt defiance of the will of the legislature or calculated disregard of the common law and when the reception of the evidence thus provided does not demean the court as a tribunal whose concern is in upholding the law.
[43] Bunning v Cross, 78 (Stephen & Aickin JJ).
In the present case, as I have said, the failure of the investigating officers to give a full caution to Mr Forth was isolated and unintentional. In my view, the admission of the 22 October interview would not give the appearance of curial approval of any impropriety and was not in conflict, or at variance with, the protection of societal norms. In light of the honest, but mistaken, assessment by the officers that Mr Forth be treated as a witness, rather than as a suspect, the public interest in protecting persons from unfair and unlawful treatment was more than outweighed by the public interest in the admission of reliable and probative evidence relevant to a charge of murder.
For these reasons, I refused the application to exercise the public policy (or Bunning v Cross) discretion.

Conclusion

Subject to the edits that have already been made, I concluded that the 22 October interview could be admitted as part of the State case.

I certify that the preceding paragraphs comprise the reasons for decision of the Supreme Court of Western Australia.
MJM
Principal Associate to the Hon Chief Justice Quinlan
5 AUGUST 2025