The State of Western Australia v Ng [No 2] - [2025] WADC 62

JURISDICTION : DISTRICT COURT OF WESTERN AUSTRALIA
IN CRIMINAL

LOCATION:   PERTH
CITATION:   THE STATE OF WESTERN AUSTRALIA -v- NG [No 2] [2025] WADC 62
CORAM:   ASTILL DCJ
HEARD:   1 & 16 SEPTEMBER 2025
DELIVERED          :   19 SEPTEMBER 2025
FILE NO/S:   IND 109 of 2023
BETWEEN:   THE STATE OF WESTERN AUSTRALIA

AND
KENNY MENG WAI NG

Catchwords:

Criminal law - Fitness to stand trial - Whether accused has a mental impairment for the purpose of s 9 of the Criminal Law (Mental Impairment) Act 2023 (WA) - Meaning of mental impairment - Whether significant cognitive impairment amounts to mental impairment

Legislation:

Criminal Code (WA)
Criminal Law (Mental Impairment) Act 2023 (WA)
Criminal Law (Mentally Impaired Accused) Act 1996 (WA)
Criminal Procedure Act 2004 (WA)

Result:

Accused not fit to stand trial
Order for special proceeding to take place

Representation:

Counsel:

The State of Western Australia	:	Ms C Aynsley
Accused	:	Ms P S Chong

Solicitors:

The State of Western Australia	:	State Director of Public Prosecutions
Accused	:	Patti Chong Lawyer

Case(s) referred to in decision(s):

GAE v The State of Western Australia [2015] WADC 5
R v Radford (1985) 20 A Crim R 388
The State of Western Australia v Altieri [2024] WADC 31
The State of Western Australia v IMK [2018] WADC 171
The State of Western Australia v KC (a pseudonym) [2019] WADC 179
The State of Western Australia v Ng [2025] WADC 42
The State of Western Australia v Siddique [No 2] [2016] WASC 358

ASTILL DCJ:

History of proceedings

The relevant history of these proceedings has been summarised in my previous decision of The State of Western Australia v Ng[1] (previous reasons) and need not be repeated.
[1] The State of Western Australia v Ng [2025] WADC 42 [1] - [12].
Having determined in my previous reasons that s 99 of the Criminal Procedure Act 2004 (WA) (CPA) did not preclude the operation of pt 3 div 2 of the Criminal Law (Mental Impairment) Act 2023 (WA) (the Act), I listed a fitness inquiry under s 29 to take place before me on 1 September 2025.
At the time of conducting the inquiry, the accused person Mr Ng was legally represented by Ms Chong. At her request, the proceedings were conducted in the absence of Mr Ng due to a concern that the nature of the proceedings and his ongoing participation in them were having an adverse effect upon his mental condition.
Whilst conscious of the need to provide Mr Ng with a fair hearing in accordance with ordinary procedures,[2] as well as not interfering with his right to be involved in proceedings,[3] those needs must be balanced against the need to ensure Mr Ng is provided with the best possible treatment, care and support.[4] Given Mr Ng was legally represented, I was prepared to proceed in Mr Ng's absence so as to achieve that balance.[5]
[2] Section 7(1)(b)(iii) of the Act.
[3] Section 7(1)(b)(v) of the Act.
[4] Section 7(2)(c) of the Act.
[5] Pursuant to s 14 of the Act, the provisions of the CPA, including s 88, will apply 'with the necessary modifications'. Section 88(1) defines 'proceedings' as including 'at trial'. To the extent any modification of 'proceedings' is required to incorporate an inquiry under pt 3 div 2 of the Act, I make such modification.
As part of that inquiry, Mr Ng called Dr Cindy Cabeleira (neuropsychologist) and Dr Gosia Wojnarowska (psychiatrist) for the purposes of supplementing reports both had previously provided to this court pursuant to s 29(3).

Applicable legal principles

In carrying out the exercise of any function under the Act I must have regard to the principles set out in s 7(2). Section 8 provides my paramount consideration is the protection of the community. I also have had regard to the objects of the Act which are provided for in s 7(1).
Division 2 provides for the process that a court must undertake when determining the question of an accused's fitness to stand trial when the question arises. Section 29 of the Act provides for how the court is to conduct the inquiry.
An accused person will be presumed mentally fit to stand trial until the contrary is found.[6] The question of whether an accused person is unfit to stand trial can be raised at any time before or during a trial.[7] The question is to be decided on the balance of probabilities.[8] In determining the question, the court may inform itself as it considers appropriate.[9]
[6] Section 27 of the Act.
[7] Section 28 of the Act.
[8] Section 29(1) of the Act.
[9] Section 29(2) of the Act.
An accused person will be unfit to stand trial if a court is satisfied:
(a)the accused has a mental impairment;
(b)the mental impairment renders the accused unable to do one or more of the matters set out in s 26 of the Act; and
(c)the accused will not become fit within six months.
If found to be unfit to stand trial, an order must be made under s 37.[10] Once an unfitness finding is made by this court, the only order that can be made is for a special proceeding to take place under pt 3 div 2, subdivision 3.[11]
[10] Section 35(1) of the Act.
[11] Section 37(3) of the Act.
At the commencement of these proceedings the State advised the court it 'accepts that Mr Ng has difficulties and certainly doesn't dispute that he has significant cognitive difficulties'.[12] What was identified as being the 'sole issue' for resolution was whether those 'significant cognitive difficulties' amounted to a mental impairment for the purposes of the Act.
[12] ts 132.
As can be seen, in addition to the three issues for resolution outlined above at [9], the State's position raises a preliminary issue that must be resolved regarding what constitutes a mental impairment for the purposes of the Act.

What constitutes a mental impairment?

Section 9 of the Act defines a 'mental impairment' as any, or a combination of, the following:
(a)an intellectual disability;
(b)a mental illness as defined in The Criminal Code (the Code) section 1(1). Section 1(1) of the Code defines a 'mental illness' as 'an underlying pathological infirmity of the mind, whether of short or long duration and whether permanent or temporary, but does not include a condition that results from the reaction of a healthy mind to extraordinary stimuli';
(c)an acquired brain injury;
(d)dementia.
The definition of 'mental illness' is reflective of what was said by King CJ in Radford[13] when considering the meaning of 'disease of the mind'. There he considered a 'disease of the mind' to include 'a major mental illness or psychoses such as schizophrenia are clearly diseases of the mind as are physical diseases, such as psychomotor epilepsy and arteriosclerosis, when they affect the soundness of the mental faculties'.
[13] R v Radford (1985) 20 A Crim R 388, 396.
The reference to a 'pathological infirmity of the mind' within s 1(1) of the Code has been interpreted as referring to 'an underlying infirmity of the mind caused by disease or abnormal bodily affection or condition'.[14]
[14] The State of Western Australia v Siddique [No 2] [2016] WASC 358 [46] (Jenkins J).
However, the remaining terms 'intellectual disability', 'acquired brain injury', and 'dementia' are not defined within the Act.
Each of these terms can hold a technical meaning for diagnostic purposes. The State, in its submissions, proceeds on an assumption that the diagnostic meanings, and associated criteria within them, equate to the same meaning as to how those terms are used in s 9.[15] The correctness of that assumption, and whether it holds textual support from the Act, must be examined.
[15] See State's supplementary outline of submissions dated 9 September 2025 (State's supplementary submissions) pars 19, 20, 22.
As noted above, s 7(1) of the Act provides what the objects of the Act are. When one has regard to s 7(1)(a) and s 7(1)(b)(i) ‑ (v) it is clear the Act is not for diagnostic purposes.
Section 7(1)(b)(i) provides it is the object of the Act 'to ensure persons with mental impairment who are charged with an offence are identified early in their contact with the justice system'. Such an object does not support a meaning to be afforded to the Act that places restrictive or prescriptive diagnostic criteria on what might amount to a 'mental impairment'.
Similarly, although s 7(2)(c) provides that 'persons with mental impairment in the justice system should be provided with the best possible treatment, care and support', it is evident that the Act does not operate solely as a therapeutic scheme. Individuals are not identified under the Act simply to facilitate treatment. Rather, consideration of appropriate treatment arises once it is established that a person's mental impairment affects their capacity to participate in ordinary criminal processes.
Diagnostic criteria provided for by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM‑5) and the International Classification of Diseases (ICD) provide useful tools for the identification and treatment of disorders. But these are for medical, not legal, purposes. Mr Ng's matter provides a useful illustration of why the distinction is material.
There is a consensus in the opinions held by the experts who reviewed Mr Ng that he has widespread cognitive impairment. That cognitive impairment is of a level consistent with what one would expect from someone with an intellectual disability or an acquired brain injury or dementia. There is also a consensus that Mr Ng's cognitive impairment deprives him of the ability to understand some, or most, of the criteria provided for in s 26 of the Act.
The origin and cause of Mr Ng's cognitive impairment are both plainly important for diagnostic and treatment purposes. To the extent the court may be required to make an order under pt 5 of the Act, then this could have some significance. This seems to be what s 7(2)(c) specifically contemplates.
But it would be a peculiar outcome, and one seemingly at odds with the objects of the Act as outlined in s 7(1), if Mr Ng were found fit to stand trial merely because his acknowledged cognitive impairment could not be diagnostically classified as an intellectual disability, or an acquired brain injury, or dementia.
Notwithstanding, the State maintains that because none of the examining specialists, particularly Dr Cabeleira and Dr Wojnarowska, were able to make a clinical diagnosis of Mr Ng's condition beyond describing it as a 'cognitive impairment', that this cannot be regarded as an intellectual disability for the purposes of the Act. In support of this submission the State has referred[16] to Wager DCJ's decision (as her Honour then was) in GAE v The State of Western Australia.[17]
[16] ts 177.
[17] GAE v The State of Western Australia [2015] WADC 5 (Wager DCJ) (GAE).
In that decision, her Honour observed that 'the definition of mental impairment in s 8 of the [1996] Act[18] does not include cognitive impairment'.[19] This is the part of her Honour's reasons that the State relies upon in support of its submission that the meaning of 'intellectual disability' does not include a cognitive impairment. With respect, that interpretation of her Honour's reasoning overstates what her Honour was saying.
[18] Criminal Law (Mentally Impaired Accused) Act 1996 (WA) (the 1996 Act).
[19] GAE [16].
In that matter her Honour was resolving a divergence in the opinions offered by Ms Vidovich (as she then was) and Dr Brett. Ms Vidovich had opined the accused[20]
does not have an intellectual disability … [h]owever, his limited access to consistent and specialised academic input and intervention during his early developmental years and schooling has likely meant that he was not afforded the opportunity to cultivate his verbal language skills/knowledge, and literacy and numeracy.
[20] GAE [13].
Dr Brett's opinion was the accused had a mental impairment, but could not say where that impairment came from, nor was he able to say it was related to his cognition, but he did say it was consistent with an intellectual disability. He was of the view the neuropsychological testing pointed towards a functional impairment or organic impairment, such as from a head injury, but did not think it was consistent with brain damage.
In attempting to explain the difference in opinion between Ms Vidovich's opinion that the accused did not hold an intellectual disability, and Dr Brett's opinion that he did, Dr Brett said there was no clinical definition of intellectual disability so far as mental impairment is concerned in respect of s 8 of the 1996 Act and 'that's one of the problems with it'. Dr Brett's opinion was the accused had a 'cognitive impairment' but that it was 'more semantics rather than anything else'.
The State treats her Honour's words as interpretive when in truth they were descriptive of her factual conclusion and her reason for rejecting Dr Brett's opinion. This much is evident from the following passages:[21]
16… There is no evidence that,[22] given Ms Vidovich's findings that Mr E did not have an intellectual disability, from which the court can infer that some cognitive impairment fits within the definition of an intellectual disability. Although I am satisfied Mr E has some cognitive impairment I am not satisfied that Mr E has a mental impairment as defined in s 8 of the Act and therefore the questions posed by s 9 of the Act do not apply.
17However, if I am wrong and a cognitive impairment is a form of intellectual impairment divorced from intellectual impairment as neuropsychologically defined, I would then be required to consider whether, on a balance of probabilities after inquiring into the question and informing myself, I am able to answer the questions posed in s 9 of the Act in the negative.
[21] GAE [16] - [17].
[22] With respect to her Honour, the word 'that' appears to have been included by error.
Her Honour's reference to 'if I am wrong' shows her Honour then moved to contemplate an alternative scenario to her original one. The alternative scenario was one where the kind of cognitive impairment Dr Brett was considering is separate ('divorced') from the kind of intellectual impairment Ms Vidovich had considered, and excluded, when offering her opinion. The fact her Honour expressed this as the alternative to the original scenario where she expressed the view outlined above at [26] suggests the original scenario contemplated a meaning of 'intellectual impairment' that was not divorced from cognitive impairment.
When her Honour observed that 'cognitive impairment' was not included within the definition of 'mental impairment', she was not narrowing the operation of s 8. Rather, she was explaining that the elements of the accused's condition described by Dr Brett as a 'cognitive impairment', to the extent they could amount to 'intellectual disability', had already been considered and excluded by Ms Vidovich. Any remaining features that fell outside of what Ms Vidovich was referring to as an 'intellectual disability' could not constitute a mental impairment in their own right given the absence of a distinct category of 'cognitive impairment' within 'mental impairment'.
Put simply, Ms Vidovich's testing led her to conclude there was no intellectual disability. Having accepted that opinion, her Honour found there was no intellectual disability within the meaning of the Act. That factual finding left no scope for Dr Brett's description of the accused's condition as a 'cognitive impairment' to satisfy the meaning of 'intellectual disability' provided for in s 8 in that case. It was not a finding by her Honour that 'cognitive impairment' is excluded, as a matter of interpretation, from the concept of 'intellectual disability' or could not constitute a 'mental impairment'.
It is clear her Honour's reasons were not intended to be a substantive interpretation of the definition of 'intellectual impairment' for the purposes of the 1996 Act. At no point does her Honour make any attempt to engage with the concept or meaning of 'intellectual disability' or why it would not, as a matter of construction, include 'cognitive impairment', nor do her reasons provide any textual analysis supporting such a construction.
Further, if her Honour's reasons were intended to have been authority for the construction in the way the State submits, then it is regrettable this was not drawn to the court's attention in The State of Western Australia v IMK.[23]
[23] The State of Western Australia v IMK [2018] WADC 171 (Sleight CJDC) (IMK).
In that matter the accused had suffered cerebral ischaemia which caused a cognitive impairment affecting executive function. Not only did Sleight CJDC conclude the accused suffered from a cognitive impairment which constituted an intellectual disability 'and therefore falls within the definition of a mental impairment within the meaning of the Act' he did so after the State had made concessions to that effect.[24] His Honour described those concessions as being 'appropriate'.
[24] IMK [18].
Similarly, in The State of Western Australia v KC[25] the fact the accused had 'significant risk factors for cognitive impairment' was one of the factors which satisfied his Honour the accused had a 'mental impairment'. Notably, his Honour did not make a finding any more specific than that regarding the nature of the impairment.
[25] The State of Western Australia v KC (a pseudonym) [2019] WADC 179 [34(a)] (Sleight CJDC).
More recently, in The State of Western Australia v Altieri[26] Gillan DCJ, when considering the meaning of 'intellectual disability' for the purposes of the 1996 Act noted '[t]he term 'intellectual disability' is not further defined and so has its ordinary meaning'.[27] In considering the meaning of 'intellectual disability' under the current Act her Honour observed:[28]
Under the 2023 Act the term 'intellectual disability' is not further defined. Accordingly, the term 'intellectual disability' under the 2023 Act would appear to have the same meaning as under the 1996 Act.
[26] The State of Western Australia v Altieri [2024] WADC 31 (Gillan DCJ) (Altieri).
[27] Altieri [12].
[28] Altieri [24].
Again, to the extent that there was an apparent inconsistency between Wager DCJ's decision in GAE and Gillan DCJ's decision in Altieri, it appears that inconsistency was not drawn to Gillan DCJ's attention when considering the meaning of 'intellectual disability'.
In my view, any apparent inconsistency between the way in which Wager DCJ dealt with the interaction between 'intellectual disability' and 'cognitive disability', and the way the court has subsequently dealt with the meaning of 'intellectual disability' is readily reconciled in the way I have addressed above at [34]. I see no reason why I should depart from the approach adopted by Gillan DCJ in Altieri.
In determining what the 'ordinary meaning' of 'intellectual disability' might be, the following definitions give some insight:[29]
(a)intellectual: of or relating to the intellect;
(b)intellect: the power or faculty of the mind by which one knows, understands, or reasons, as distinct from that by which one feels and that by which one wills; the understanding or mental capacity, especially of a high order;
(d)disability: lack of competent power, strength, or physical or mental ability, incapacity; a condition which restricts a person's mental or sensory processes, or their mobility;
(e)cognitive: (adj) cognition; the act or process of knowing, perception; the product of such a process, thing thus known, perceived.
[29] Macquarie Dictionary (9^th ed, 2023).
Similarly, 'dementia'[30] is defined as 'a state of mental disorder characterised by impairment or loss of the mental powers; commonly an end result of several mental or other diseases'.
[30] Macquarie Dictionary (9^th ed, 2023).
Mosby's Dictionary[31] defines:
(a)intellectual disability: a disorder characterised by subaverage general intellectual function with deficits or impairments in the ability to learn and to adapt socially. The cause may be genetic, biological, psychosocial or sociocultural;
(b)intellect: the power and capacity of the mind for knowing and understanding, as contrasted with feeling or with willing;
(c)cognitive: pertaining to the mental processes of comprehension, judgment, memory and reasoning, as contrasted with emotional and volitional processes;
(d)cognition: the mental process characterised by knowing, thinking, learning, understanding and judging;
(e)dementia: acquired impairment of cognition sufficient to affect activities of daily living but without altered consciousness or psychiatric illness.
[31] Mosby's Dictionary of Medicine, Nursing & Health Professions (3^rd ed, 2019).

As can be seen, the meanings of 'intellect' and 'intellectual' embrace the concepts of the mind, understanding and reasoning. It follows that an 'intellectual disability' must refer to a condition that has reduced or impaired the ability of a person's mind to understand or reason.
When one compares this to the meaning of 'cognition' it is clear there is a significant overlap between 'cognition' and 'intellect' with the two concepts being closely related.
However, whereas cognition appears to encompass the broader mental processes of acquiring knowledge through perception, processing and then storing that knowledge through memory, and then drawing from that knowledge to reason and problem solve, the intellect focuses on the latter part within cognition which relates to the higher order processes of reasoning, analysis and engaging in complex and abstract thinking.
One can see that, in some cases, the distinction between 'intellect' and 'cognition' may be material. But it is difficult to immediately see how that would be the case in this matter. The fact that a cognitive impairment will not always amount to an intellectual disability does not mean that a cognitive impairment cannot fall within the meaning of an intellectual disability.
Similarly, when one looks at the different meanings of 'dementia' it is apparent what they incorporate are concepts of an impairment to the operation of a person's mind resulting in a diminishment of functional ability, brought about by some disease or condition affecting the brain.
What is particularly clear, however, is that none of these definitions require the collateral or corroborative evidence required by the diagnostic criteria in the DSM‑5 or ICD. I see no basis for this court to import such a requirement when interpreting the terms 'intellectual disability' or 'dementia' under s 9 of the Act.
In relation to 'acquired brain injury' this, in my view, is even easier to define. Here 'acquired' is simply a reference to an injury to the brain that has been sustained from after birth onwards. However, to have any relevance to the discharge of the court's function under pt 3 of the Act, obviously that brain injury must cause some level of impairment to the accused's understanding of one or more of the criteria contained within s 26. So, again, here the reference to an 'acquired brain injury' refers to something more than simply an injury to the brain following birth but, to be relevant, an injury to the brain that affects the person's ability to understand or reason.
When one examines the collective meanings of 'intellectual disability', 'acquired brain injury', 'dementia', and the meaning of 'mental illness' as provided for by s 1(1) of the Code and the manner in which it has subsequently interpreted, there is a conceptual commonality between all four terms in that:
(a)the impairment originates from an underlying non‑self-induced condition, whether that is a disease, injury, abnormality or pathological change, as opposed to an impairment that has been brought about by virtue of the mind's temporary reaction to an external circumstance;
(b)the underlying condition causes a reduction in the person's mental capacity, specifically in relation to the person's ability to reason, understand or exercise proper judgment; and
(c)that reduction has a functional consequence upon the person.
Put simply, each refers to an underlying condition or injury of the brain or mind that materially impairs a person's cognitive functioning, including their ability to understand, reason, or exercise judgment, and can be distinguished from temporary or non‑pathological responses to external stimuli. The resultant consequence is the diminution in the person's functional mental capacities.
In construing the meanings to be attributed in the way that I have, one can see that the essential question is to what extent the person's mental functioning has been impaired. None of this is surprising when one remembers that the four terms used in s 9(a) ‑ s 9(d) are collectively endeavouring to define the meaning of 'mental impairment'. To the extent that a person's mental functioning may be impaired due to cognitive impairment, there does not appear to be any textual justification for why that would not amount to a 'mental impairment'.

The evidence

Ancillary materials

As noted at [6] ‑ [9] of my previous reasons, this matter initially came before me for the purposes of sentencing Mr Ng. Reports had been ordered for that purpose. Those reports were prepared by Dr Nicholas Ho, psychiatrist, dated 7 March 2023[32] and Ms Claire Lynn, psychologist, dated 2 March 2023.[33]
[32] Exhibit 4 (Dr Ho's report).
[33] Exhibit 5 (Ms Lynn's report).
These reports had not been prepared pursuant to s 29(3) of the Act. Notwithstanding, it was agreed by the parties I could have regard to the contents of these reports pursuant to s 29(2) and they were received into evidence on that basis. Neither author was called as part of the inquiry.
Ms Lynn reports that:[34]
A continual theme during [the] interview was Mr Ng's difficulty with language, regardless of whether he was listening to the writer and responding in English or to the interpreter. The interpreter struggled throughout while he reiterated that Mr Ng was not answering [the] questions … [o]verall, Mr Ng presented as confused, disorientated, potentially anxious and unable to understand or respond through language and comprehension limitations.
[34] Ms Lynn's report, page 2, par 1.
Most of the background history was obtained from Mr Ng's brother as '[a]cquiring clear and consistent information from [Mr Ng] was not possible at any time'.[35]
[35] Ms Lynn's report, page 2, par 1.
Mr Ng's brother reported that Mr Ng did not speak until somewhere between 5 to 7 years old. He has always been highly reliant on his family as he has never demonstrated a capacity to live independently. Mr Ng was never formally assessed for any condition despite having learning difficulties. He ceased schooling at approximately grade 6 or 7.[36]
[36] Ms Lynn's report, page 3, par 3.
Mr Ng's brother suggested there had always been developmental delays and limitations in Mr Ng's capacity that have impeded communication, learning, understanding and managing the demands of independent living.[37] Ms Lynn concluded that[38]
[t]he assessment revealed that [Mr Ng] presented with severe developmental delay in relation to speech and language … demonstrated limited adaptive behaviour and associated skills … and his presentation raised further questions around his cognitive functioning and capacity …
[37] Ms Lynn's report, page 4, par 6.
[38] Ms Lynn's report, page 5, par 10.
She suggested a disability specific assessment may be necessary to clarify Mr Ng's cognitive function and capacity.
Dr Ho reported that when examining Mr Ng '[i]t was extremely difficult to elicit a history from Mr Ng, who appeared to misunderstand questions posed of him, or respond in a longwinded or at times irrelevant manner'.[39] Similar difficulty was experienced when questioning regarding the index offending with Dr Ho noting he was unable to elicit the 'underlying emotions, motivations, cognitions, and circumstances surrounding his offending' despite multiple efforts to rephrase questions and spending over 45 minutes separated into three discrete blocks endeavouring to do so.[40]
[39] Dr Ho's report, page 3, par 5.1.
[40] Dr Ho's report, page 3, par 4.13.
Dr Ho conducted 'brief cognitive screening' but Mr Ng experienced significant difficulty.[41] He provided the diagnosis of '[a]pparent cognitive impairment for further investigation'.[42] There was no evidence of a serious mood, anxiety or psychotic disorder nor a diagnosis of 'major mental illness'.[43] However, given the difficulties Dr Ho sustained in obtaining reliable information from Mr Ng and the apparent incongruity between the poor cognitive testing coupled with matters Mr Ng was saying, it was impossible for Dr Ho to provide any degree of diagnostic certainty in the absence of collateral information.[44] This presented a significant limitation to the extent that Dr Ho could provide any reliable assessment.
[41] Dr Ho's report, pages 8 - 9, pars 10.8 ‑ 10.14.
[42] Dr Ho's report, page 9, pars 11.3 ‑ 11.5.
[43] Dr Ho's report, page 9, par 11.6.
[44] Dr Ho's report, page 10, par 11.0.
For this reason, Dr Ho recommended further medical evaluation for possible neuropsychological causes of his apparent cognitive impairment.

Dr Cindy Cabeleira

Dr Cabeleira provided two reports dated 16 January 2024[45] (first report) and 23 October 2024[46] (second report). The first report was prepared following Dr Ho's recommendation and in anticipation of the sentencing proceedings that were to take place. Similarly, this report was also received into evidence pursuant to s 29(2). The second report was obtained pursuant to s 29(3) of the Act.
[45] Exhibit 1 (Dr Cabeleira's first report).
[46] Exhibit 2 (Dr Cabeleira's second report).
Dr Cabeleira initially saw Mr Ng across three sessions on 24, 29 November and 1 December 2023 with the assistance of a Cantonese interpreter. She observed he presented with a significant cognitive impairment over and above what might be expected from his hearing impairment and language barrier.[47]
[47] Dr Cabeleira's first report, page 3.
She reviewed a CT scan of Mr Ng's head which was performed on 1 January 2023.[48] The scan showed 'volume loss and signs of ischaemia'.[49] A further scan on 16 July 2023 identified 'patchy white matter hypoattenuation consistent with chronic small vessel disease. Punctate low attenuation foci in the right thalamus'[50] however there was no sign of cerebral injury.
[48] Dr Cabeleira's first report, page 5, par h.
[49] A medical condition caused by the restriction of blood supply causing lack of oxygen.
[50] Dr Cabeleira's first report, page 5, par i.
At the conclusion of her first report she opined:[51]
(a)Mr Ng demonstrated areas of 'mild to marked' cognitive impairment with 'significant' deficits in visuomotor speed, attentional capacity, auditory working memory and aspects of higher executive functioning. Features of the executive functioning impairment included divided attention, indicators of concrete and rigid thinking and issues with self‑monitoring and mental tracking.
(b)His cognitive profile was characterised by significant slowing, verbal language deficits and attentional executive weaknesses which were likely to negatively impact on, and cause, variability in his daily memory functioning.
(c)The cognitive profile testing was not indicative of an intellectual developmental disorder however the 'significant' cognitive deficits are considered to be longstanding and neurodevelopmental in nature.
(d)His cognitive and adaptive functioning deficits appear to have worsened over time, partly due to his poorly managed medical conditions and vascular risk factors. He is at significant risk of further decline.
(e)He is at risk of the possible emergence of a neurodegenerative condition such as dementia.
(f)Further assessment of Mr Ng's decision‑making capacity was 'strongly recommended' in order to ascertain whether a guardian and administrator needed to be formally appointed.
[51] Dr Cabeleira's first report, pages 17 - 18.
In preparing her second report, Dr Cabeleira again interviewed Mr Ng, this time in a single session that lasted four hours. Mr Ng once again had the assistance of a Cantonese interpreter but, once again, Dr Cabeleira experienced a level of difficulty in carrying out the interview that exceeded the difficulty she would have expected to be caused by the language difficulty and Mr Ng's hearing impairment.[52] She observed he continued to present with significant cognitive impairment as well as noting generalised slowing.
[52] Dr Cabeleira's second report, page 3.
Further neuropsychological testing carried out on this occasion showed that Mr Ng continued to demonstrate difficulty with working memory. Notwithstanding the difficulties Mr Ng experienced in carrying out the testing, Dr Cabeleira was satisfied the testing still appeared to be a valid reflection of Mr Ng's cognitive capacity.
The testing on this occasion suggested Mr Ng experienced the following limitations:[53]
(a)His immediate auditory attention span and auditory working memory were assessed as being extremely low and borderline respectively.
(b)His processing speed was extremely low.
(c)Verbal and language abilities could not be quantitatively assessed due to the language difficulties Mr Ng exhibited. These difficulties continued notwithstanding efforts made to simplify testing.
(d)His higher level visuoconstructional skills were well‑intact, being assessed as high average.
(e)Verbal learning and memory functions could not be assessed due to his significant language impairment. A modified test was administered utilising a picture memory test. Mr Ng experienced significant difficulty over repeated trials. His learning and memory function was considered to be negatively impacted by attentional and executive deficits.
(f)Weakness was seen across a number of Mr Ng's executive skills. His simple visual strategy formation/problem‑solving was impaired with very concrete and rigid thinking observed. Divided attention and cognitive flexibility were also qualitatively poor. Difficulties were also observed with Mr Ng's self-monitoring and his mental tracking.
[53] Dr Cabeleira's second report, pages 8 - 10.
In conclusion, Dr Cabeleira remained of the view Mr Ng continued to demonstrate areas of 'largely marked cognitive impairment' with 'significant' deficits in his visuomotor speed, attentional capacity, auditory working memory and aspects of his higher executive functioning. Whilst unable to be quantitatively assessed, significant language impairment was observed with frequent difficulties being seen in his inability to understand the Cantonese interpreter.
When qualitatively comparing his results to those obtained during the assessment conducted for the purposes of preparing the first report, Mr Ng's level of cognitive functioning and areas of impairment appeared to have remained stable.[54]
[54] Dr Cabeleira's second report, page 15.
She concluded that Mr Ng has a 'cognitive disability that appears longstanding and neurodevelopmental in nature and partially associated with his significant hearing impairment from birth'. That language impairment appears to have contributed to significant attentional and executive impairments. She was of the view this cognitive impairment was neurodevelopmental in nature and was likely to have largely been present since birth.[55]
[55] Dr Cabeleira's second report, page 15.
Dr Cabeleira opined that Mr Ng 'impressed as a severely (cognitively) impaired and vulnerable man with very limited informal (daily and social) supports'.[56] That neurodevelopmental cognitive condition has 'likely worsened to some degree with poorly managed medical conditions and vascular risk factors'.

Oral evidence

[56] Dr Cabeleira's second report, page 16.

Dr Cabeleira gave evidence to supplement her two reports.
She was asked to clarify the distinction drawn between an intellectual developmental disorder, such as intellectual disability, versus the widespread cognitive impairment that the testing showed Mr Ng to have. She explained the principal distinction was a diagnostic one.
An 'intellectual disability' is where a person has 'widespread cognitive deficits that are present from birth and lead to widespread deficits in daily or adaptive functioning ‑ also from birth or from childhood'[57] whereas 'cognitive disability' is 'usually for something that happens later.'[58] As can be seen, there is a degree of overlap between an intellectual disability and cognitive disability. An intellectual disability largely appears to be a subset within a 'cognitive disability' with the principal point of distinction being the onset. Where a cognitive disability is incurred after birth, this would then be assessed as an 'acquired brain injury'.[59]
[57] ts 142; ts 143.
[58] ts 142.
[59] ts 160.
In Mr Ng's case, Dr Cabeleira agreed that his widespread cognitive impairments were consistent with having been present from an early age, including from birth, but her principal difficulty in providing a diagnosis of 'intellectual disability' was the absence of corroborative evidence demonstrating an impaired ability to adapt to that cognitive impairment.[60]
[60] ts 141.
If such corroborative evidence was present, then Dr Cabeleira confirmed it would be possible Mr Ng would meet the criteria, but she would require that corroborative information as Mr Ng held some 'pockets of [relative] strength' in visual processing skills and mathematical ability, which were not findings one would commonly see in someone with an intellectual disability.[61]
[61] ts 154.
Similarly, she explained that:[62]
to identify dementia, you'd need at least one area of cognition to be significantly below or to have significantly declined from where the person was at in terms of that ability before, perhaps, but you also need corroborative history about their adaptive functioning and evidence of functional decline.
[62] ts 144.
Ordinarily, such a source of corroborative evidence would be a parent rather than a sibling, as a sibling will ordinarily be similar in age which make any assessment of intellectual functioning unreliable as it is formed through the perspective of a child.[63]
[63] ts 145.
Mr Ng lives with his mother who provides him with day‑to‑day support. She is his only remaining parent. She is unable to provide a reliable corroborative history as she has dementia. Mr Ng's only other source of collateral corroboration was his younger brother who provides sporadic support but, due to the limited involvement he has with Mr Ng, he was not considered to be a reliable source from which to make comparative assessments.
Nevertheless, Dr Cabeleira confirmed Mr Ng's current level of cognitive impairment coupled with the presence of volume loss seen in the CT scan on 1 January 2023 would otherwise be consistent with dementia or, at the very least, has exacerbated a pre‑existing injury sustained from childhood.[64] She clarified that the apparent stability she identified in her second report did not suggest there had not been further deterioration but, rather, once testing fell beneath a certain minimum baseline it was impossible to reliably determine if there had been any further decrease.[65]
[64] ts 150 - ts 151.
[65] ts 151.
Even in the absence of being able to provide a diagnosis of dementia, Dr Cabeleira confirmed the small vessel disease evidenced from the CT scan on 16 July 2023 was likely to have contributed to Mr Ng's cognitive impairment and was consistent with the ischaemic injury and volume loss seen in the CT scan on 1 January 2023.[66]
[66] ts 149.
Further, she noted Mr Ng's significant hearing impairment may be a complicating factor to any diagnosis as the hearing impairment itself could be partially responsible for his widespread cognitive deficits.[67] She explained early onset hearing impairment where there was an absence of supports to manage it can affect a child's language development, problem solving, executive functional development, reasoning and memory.[68] On this basis alone, Dr Cabeleira suggested the hearing impairment had the capacity to have a 'profound impact' upon Mr Ng's cognitive impairment.[69]
[67] ts 141.
[68] ts 155; ts 158; ts 159.
[69] ts 160.
In summary, Dr Cabeleira was satisfied based upon the testing and the information she had received from Mr Ng, that he held a widespread cognitive impairment.[70] Her difficulty was in providing a diagnostic classification for that cognitive impairment due to an inability to pinpoint its onset because of the absence of reliable corroborative history. She opined the possible diagnoses were:[71]
(a)If the cognitive impairments had been present from birth, this would meet the criteria for intellectual disability.
(b)Mr Ng's significant hearing impairment, from an early age, could have impacted upon his cognitive development.
(c)An in utero event that could have resulted in brain injury.
(d)Dementia, if corroborative evidence could be obtained to show a deterioration in functioning.
(e)An emerging neurodegenerative condition that could not be identified due to Mr Ng's poor performance in the testing.

Dr Gosia Wojnarowska

[70] ts 147.

[71] ts 146 - ts 147.

Pursuant to s 29(3) of the Act, Dr Wojnarowska provided a report dated 22 March 2025[72] addressing the question of Mr Ng's fitness to stand trial. As part of that assessment, she conducted a meeting on 13 March 2025 with Mr Ng with the assistance of a Cantonese interpreter. That meeting was of 'relative short duration' due to Mr Ng prematurely terminating it. Notwithstanding, Dr Wojnarowska was still able to provide an opinion based on the information she was able to obtain from Mr Ng during the interview, coupled with the materials she received to assist in the preparation of the report.[73]
[72] Exhibit 3 (Dr Wojnarowska's report).
[73] Dr Wojnarowska's report, page 2, par 7.
Mr Ng claimed to have remembered being assessed by Dr Wojnarowska three years previously and was familiar with the interview location, having been there a 'long time ago'. This was, in fact, Dr Wojnarowska's first time meeting Mr Ng.[74] Upon specific questioning by Dr Wojnarowska as to the purpose for why Mr Ng was being assessed, he maintained a denial of his alleged offending and was observed to become increasingly agitated. It was shortly thereafter that he terminated the interview prematurely.
[74] Dr Wojnarowska's report, page 5, pars 26 - 27.
Despite the assistance of the Cantonese interpreter, Dr Wojnarowska experienced similar difficulties to Dr Cabeleira in the answers he provided. She notes the content of his answers were 'difficult to assess due to illogicality of his answers'. The interpreter confirmed a number of Mr Ng's answers were not grammatically correct. His presentation suggested his cognition, insight and judgement were all significantly impaired.[75]
[75] Dr Wojnarowska's report, page 6, par 34.
In addressing the question of whether Mr Ng has a 'mental illness or mental impairment' she confirmed he did not present with a 'major psychiatric disorder such as psychosis or mood disorder'.[76]
[76] Dr Wojnarowska's report, page 6, par 35.
However, Dr Wojnarowska opined Mr Ng 'has a confirmed cognitive deficit, most likely related to complications related to premature birth and progressive neurodegenerative disorder related to vascular dementia'.[77] She was of the view the likely cause of the 'enduring cognitive deficit' was due to prematurity. Dr Cabeleira notes in her first report that Mr Ng's brother advised Mr Ng was born 'very premature' and was 'reportedly the size of an adult's palm/hand at birth'.[78]
[77] Dr Wojnarowska's report, page 6, par 37.
[78] Dr Cabeleira's first report, page 10 par 7a.
Despite refusing to answer any of Dr Wojnarowska's questions in relation to the charge or court matters, Dr Wojnarowska still offered the opinion that he 'would have no understanding of the Australian legal process'[79] and he was unfit to plead and unfit to stand trial.[80]

Oral evidence

[79] Dr Wojnarowska's report, page 7, par 41.

[80] Dr Wojnarowska's report, page 7, par 42.

Dr Wojnarowska was called to give oral evidence to supplement her report. She confirmed she was able to exclude the operation of any of the 'major mental illnesses' like schizophrenia, schizoaffective disorder and bipolar disorder.[81]
[81] ts 167.
As to the possibility of an acquired brain injury, her answer was 'well we don't know really'. The inability to say with any degree of certainty was due to an absence of any brain imaging to compare against.[82] However, in offering this opinion it was clear Dr Wojnarowska was referring to a traumatic brain injury where the cognitive impairment was caused by external insult, and was not intending to exclude an impairment which had been acquired subsequent to birth.[83]
[82] ts 167.
[83] ts 168.
In relation to dementia, she could not 'commit [her]self' to such a diagnosis,[84] seemingly for similar reasons to Dr Cabeleira. However, Dr Wojnarowska did appear to be prepared to go slightly further by noting that if the claims Mr Ng made to her that he worked upon arrival in Australia in 1987 were in fact correct, then this would give some indication of his level of functional decline[85] suggestive of dementia.[86] Collateral information received from Mr Ng's brother suggested a history of work as a kitchen hand, but Mr Ng was often terminated from these jobs as he was unable to properly follow instructions or demonstrated difficulty in carrying out the tasks he was responsible for.[87]
[84] ts 167.
[85] ts 163 - ts 164.
[86] ts 167.
[87] Ms Lynn's report, page 3, par 3; Dr Cabeleira's first report, page 10, par 7b.
Additionally, she shared the view expressed by Dr Cabeleira that the neuroimaging was suggestive of vascular dementia.[88] However, she would not be able to provide a diagnosis or a concluded view regarding vascular dementia due to the absence of the corroborative history.[89]
[88] ts 167.
[89] ts 172.
Dr Wojnarowska offered the additional explanation that vascular dementia is a condition that creates a 'stepwise' decline rather than a progressive one as cognitive deterioration will be associated with the occurrence of an 'infarct'.[90] An infarct is the necrotic damage resulting from a loss of oxygen, which can be caused by an ischemic event.
[90] ts 164.
Because further cognitive deterioration would not be expected to be seen until a new infarct occurs, Dr Wojnarowska suggested this was a likely explanation for the fact there had been no further cognitive deterioration observed in the testing carried out by Dr Cabeleira in the intervening period between her two reports.[91]
[91] ts 164.
Ultimately though, Dr Wojnarowska considered the cognitive impairment was likely to be connected to the additional risk factors caused by 'extreme prematurity'.[92] As she explained, extreme prematurity increases the risk of hypoxia after birth which can cause damage to the brain. The area of cognitive functioning likely to be impaired will be dependent on where the damage is localised, but usually the impairments are associated with loss of memory, loss of cognitive ability to perform tasks, executive dysfunction and attention.[93]
[92] ts 164.
[93] ts 165.
Her hypothesis was that Mr Ng was someone who had been born prematurely and with a severe hearing impairment which has caused cognitive vulnerability and compromise at birth. The further risks caused by vascular dementia were then superimposed over that vulnerability.[94]
[94] ts 166.
Dr Wojnarowska agreed with the reasons why Dr Cabeleira was unable to provide a diagnosis of intellectual disability and stated that it was also 'not [her] remit' to do so.[95] Nevertheless, she was of the view that Mr Ng's widespread cognitive impairments would be capable of satisfying the diagnostic definition of 'intellectual impairment' and the only thing impeding a diagnosis was the absence of the corroborative history.[96]
[95] ts 166.
[96] ts 175.
She went on to explain that the absence of an ability to do so did not mean that Mr Ng did not have a mental impairment. Her opinion was 'he is cognitively impaired … [a]nd certainly not able to process the information that [sic 'is'] required to meaningfully participate in ‑ in a trial'.[97]
[97] ts 166.

Does Mr Ng have a mental impairment?

All four experts who reviewed Mr Ng reported his apparent significant cognitive difficulty. There is nothing in the materials before me that would cause me to question Dr Cabeleira's assessment that these cognitive difficulties are widespread.
As is apparent from Dr Cabeleira's evidence, Mr Ng's cognitive 'difficulties' are more than mere difficulties ‑ they are, in truth, profound. As Dr Cabeleira said, 'the widespread nature and severity of his cognitive deficits fit or are similar to those various conditions listed in the Act'.[98] The significance as to the level of those impairments was reflected in what Dr Cabeleira described as the 'floor effect' in that Mr Ng did 'so poorly already on the test that there's no room to get worse'.[99] The only impediment to Dr Cabeleira providing a diagnosis to that effect was the absence of the corroborative history from Mr Ng's mother.
[98] ts 146.
[99] ts 151.
Relevantly, whilst Mr Ng's cognitive impairment was described as 'widespread', where he demonstrated 'significant' impairments were to the higher‑level executive functions, including limitations to his problem‑solving, strong indications of rigid, concrete and perseverative thinking and issues with self‑monitoring and mental tracking.[100] All of these limitations would fall within the realm of 'intellectual' functioning that I have discussed above at [46]. All of them were described as appearing to be 'neurodevelopmental in nature (i.e., likely and largely present since birth)'[101] and all of them were identified as having caused him 'a long history of learning difficulties and cognitive and adaptive functioning deficits'.[102]
[100] Dr Cabeleira's second report, page 15.
[101] Dr Cabeleira's second report, page 15.
[102] Dr Cabeleira's second report, page 16.
Consistent with the opinion held by Dr Cabeleira that the impairment is 'neurodevelopmental in nature', I am satisfied Mr Ng's condition was contributed to, or caused by, one or more of the following combination of matters:
(a)An ischaemic injury or insult sustained by Mr Ng whilst in utero which caused, or created vulnerability for, damage to Mr Ng's brain, producing widespread cognitive impairment in the manner hypothesised by Dr Wojnarowska above at [99] ‑ [100].
(b)Mr Ng's profound hearing impairment from an early age, which significantly impacted his expressive and receptive development of language. In turn, that expressive and receptive limitation had a widespread adverse impact by restricting the development of Mr Ng's executive functioning, specifically his ability to reason, engage in abstract thinking and his ability to form and recall memory.[103]
(c)At some point, after having been born, Mr Ng has sustained one or more infarcts caused by the onset of vascular dementia and resulting in ischaemic injury. That ischaemic injury has caused volume loss to Mr Ng's brain, significantly in the thalamus, corona radiata and the lacunar areas.[104] These are deep internal structures of the brain that have some responsibility for executive functioning.
[103] ts 159.
[104] Dr Cabeleira's first report, page 5, par 2i.
As indicated by my findings at [106], I am satisfied that Mr Ng's cognitive impairment arises from an underlying condition or injury to his brain. This impairment has materially affected the functioning of his mind, particularly in the domains of executive and attentional processes, and has consequently diminished his capacity to reason and to understand. Even in the absence of corroborative evidence from Mr Ng's mother, I am satisfied the impairment to Mr Ng's cognitive functioning is such that it would amount to an intellectual disability in the way that I have discussed the meaning of that term above at [44].
Further, as noted at [106(b)], I am satisfied there is a link between Mr Ng's hearing disability during early childhood and the significant impairment to the development of his executive functioning. For the reasons I have already outlined, Mr Ng's executive impairment has resulted in limitations to Mr Ng's ability to reason and understand. This would constitute an 'infirmity of the mind'. Similarly, Mr Ng's hearing disability would constitute an 'abnormal bodily affection or condition'. As referred to above at [15], where an 'infirmity of the mind' is caused by an 'abnormal bodily affection or condition' this will constitute a 'mental illness' for the purposes of s 1(1) of the Code. On this basis, Mr Ng's cognitive impairment is also capable of amounting to a 'mental illness'.
Finally, when one applies the meaning of 'dementia' as I have outlined above at [48], then the finding I have made at [106(b)] is capable of meeting that criteria. Regardless, the ischaemic injury, or injuries, caused to Mr Ng's brain because of one or more infarcts would constitute an acquired brain injury in the manner that I have discussed above at [50].
For the reasons I have outlined above, each of the findings I have made relating to Mr Ng's cognitive impairment are, by themselves, capable of satisfying each of the meanings provided for in s 9(a) ‑ s 9(d). Those meanings can be satisfied even in the absence of corroborative evidence and even in the absence of a diagnostic finding to that effect.
However, the definition of 'mental impairment' as provided for by s 9 does not require Mr Ng's cognitive impairment to be clearly classified or referrable to a specific condition within s 9. That is, s 9 does not require Mr Ng's cognitive impairment to be identifiable as either an intellectual disability or a mental illness or an acquired brain injury or dementia. Mr Ng will have a mental impairment if Mr Ng has 'any of, or a combination of' those conditions.
When one considers the totality of both Dr Cabeleira and Dr Wojnarowska's evidence, both independently and together, it is clear the uncertainty each expressed in providing a diagnosis for Mr Ng's widespread cognitive impairment was not because it was unclear to either doctor as to whether it had been caused by intellectual disability, mental illness, an acquired brain injury or dementia, it was because they could simply not say which one it was. There was never any question that Mr Ng's 'significant cognitive difficulties' amounted to a mental impairment for the purposes of the Act.
For the reasons I have set out, I am satisfied that Mr Ng's significant cognitive impairment constitutes a mental impairment, as defined.

Does Mr Ng's mental impairment render him unfit to stand trial?

Section 26 of the Act sets out nine criteria. An accused person who, because of a mental impairment, satisfies one or more of those nine criteria will be unfit to stand trial.
In making the assessment, the court may have regard to what extent appropriate support measures may be able to assist a person's capacity to overcome any of the criteria they would otherwise satisfy.[105]
[105] Section 32 of the Act.
In the present matter, Dr Cabeleira considered Mr Ng to satisfy eight of the nine criteria. The only criteria Dr Cabeleira was not satisfied Mr Ng met was s 26(a).[106]
[106] Dr Cabeleira's second report, page 10.
As noted above at [92], Dr Wojnarowska was unable to specifically test the criteria due to the premature termination of her interview with Mr Ng. Notwithstanding she still was able to confirm he was 'unfit to stand trial'.
During the course of her evidence she elaborated upon this by drawing reference to her collective 'experience in assessing people who are fit to stand trial' that 'the major issue in people who have limited cognitive abilities is about understanding the consequences of entering non‑guilty plea and then participating in trial and hearing the evidence and how that evidence is weighed by the justice system.'[107]
[107] ts 169.
The effect of Dr Wojnarowska's evidence was that Mr Ng may have some capacity to understand the distinction between guilty and not guilty and if 'coached' would be able to adequately explain what the role of a judge, prosecutor, defence counsel and jury was. However, where the limiting effect of his cognitive impairment would arise would be:[108]
He would not be able to understand that by saying 'I'm not guilty' that the matter would not proceed further. So he would ‑ he would, I think, think, this is just my hypothesis, by maintaining innocence, the matter would go away.
[108] ts 170.
Notwithstanding the fact that in providing the answers outlined above Dr Wojnarowska did not specifically refer to the criteria identified in s 26 of the Act, I infer from her evidence that Mr Ng would satisfy s 26(b), s 26(d), and s 26(f) ‑ (i).
The State accepts that in the event I conclude Mr Ng has a mental impairment, that he is unfit for trial and will not become fit within the next six months.[109] This is a concession that is appropriately made.
[109] State's supplementary submissions, par 27.
In relation to the assessment of the criteria under s 26, to the extent there are any inconsistencies between the opinions offered by Dr Cabeleira and Dr Wojnarowska, I prefer the opinions of Dr Cabeleira given her ability to carry out a more detailed and comprehensive assessment of Mr Ng. However, I do not see any meaningful inconsistency between Dr Cabeleira and Dr Wojnarowska's opinions. Dr Wojnarowska's opinions usefully inform when considering the more detailed assessment made by Dr Cabeleira.
For the reasons outlined by Dr Cabeleira,[110] I am satisfied Mr Ng meets the criteria contained in s 26(b)(i) of the Act.
[110] Dr Cabeleira's second report, pages 10 - 14.
In relation to s 26(a) (unable to understand the nature of the charge) Dr Cabeleira suggested Mr Ng 'was generally aware of, and able to understand, the nature of this remaining charge including the details regarding such contained the Statement of Material Facts'.[111] Nevertheless, this does seem to sit inconsistently with subsequent material contained within her report.
[111] Dr Cabeleira's second report, page 10.
For example, when explaining why Mr Ng satisfied s 26(b) (unable to give instructions to a legal practitioner representing the accused) she noted:[112]
[H]e had instructed or suggested to his lawyer that the victim … be medically examined … as he seemingly felt this would clear him of the current charges and prove that she was not sexually penetrated. When it was put to him that this would likely not 'clear' him of his charges (as indecent dealings did not require penetration and included inappropriate touching for example which is what has been alleged for the current remaining charge), he had trouble understanding this. He then continued to perseverate on his former idea of instructing his lawyer to get [the victim] medically examined throughout the 3 to 4 hours spent in his company.
[112] Dr Cabeleira's second report, page 11.
It is not necessary for me to make a finding in relation to Mr Ng's capacity to 'understand the nature of the charge' for the purposes of s 26(a). However, the above does demonstrate the difficulty encountered when endeavouring to 'compartmentalise' a widespread cognitive impairment into specific criteria, though to be clear, that is not what I am suggesting Dr Cabeleira has sought to do. Inevitably, there will be a level of overlap given many of the criteria provided for in s 26 are facets of the same concept.
For example, a person's ability to understand the difference between 'guilty' and 'not guilty' at a conceptual or definitional level may be capable of meeting the words of s 26(c). But where a person then demonstrates a fundamental inability to understand how those pleas interact within the Western Australian criminal justice system, the significance that those pleas hold and the consequences that come from them, then it is questionable whether the person actually does, for the purposes of s 26(c), understand the effect of a plea.
This is perhaps best demonstrated by Dr Wojnarowska's evidence that Mr Ng could have the capacity to know the difference between 'guilty' and 'not guilty' and therefore, arguably, fails to meet s 26(c). But if Mr Ng truly does think that by pleading not guilty and 'maintaining innocence, the matter would go away' it does suggest that the criteria in s 26(c) has been met.
During the inquiry, the State suggested that Mr Ng's prior experience of giving evidence as a witness in unrelated proceedings[113] demonstrated a sufficient level of his understanding of the process, thereby casting doubt on the genuineness of his alleged inability to do so. This was emphatically rejected by Dr Cabeleira as making 'no difference at all'.[114] Indeed, a submission was ultimately made by the prosecutor in the matter where Mr Ng did give evidence that apparent difficulties in the Mr Ng's evidence may have been self‑evidently[115] explicable because of an 'underlying cognitive issue'.[116]
[113] The State of Western Australia v Ruse (IND 149 of 2024) (Ruse).
[114] ts 158.
[115] Transcript, Ruse, District Court, 30 April 2025, 310.
[116] Transcript, Ruse, District Court, 30 April 2025, 304.

Notwithstanding the fact Mr Ng gave evidence as a special witness with measures taken to assist in that process, it is apparent those measures did not remedy the underlying difficulty. That is not surprising given the underlying difficulty is Mr Ng's impaired ability to understand. This was consistent with Dr Cabeleira's opinion, which I accept, as to why no measures would be able to adequately assist in remedying Mr Ng's unfitness to stand trial.[117]
[117] ts 157.
The fact a person, with sufficient 'coaching', can explain the role of a prosecutor, judge or defence counsel may still fall short of what is required by s 26. Similarly, the ability for a person to sit and give evidence from a remote room as a special witness simply suggests an ability to parrot or mimic what might be expected of them. It does little to suggest an ability to understand what is occurring and why.
One of the primary focuses of s 26 is on the accused person's ability to understand. The word 'understand' is specifically referred to in five of the nine criteria. For the remaining four, it is at least arguable that an incapacity to understand either underlies the criteria or is, at the very least, implicitly relevant to satisfying them.
Ultimately, what has always been evident from the material is that Mr Ng is someone who is significantly cognitively impaired. That impairment has had a marked impact upon his ability to understand, as evidenced by his considerable confusion and his perseveration on unrelated and irrational matters. Anyone who has spoken to Mr Ng, including the State,[118] has readily come to that conclusion. I am no different.
[118] Transcript, Ruse, District Court, 28 April 2025, 167.

Conclusion

I am satisfied that Mr Ng holds a 'mental impairment' as defined within s 9 of the Act.
I am satisfied that because of the mental impairment, Mr Ng is unable to do any of the things outlined in s 26(b) through to s 26(i) of the Act.
Because of the nature of the mental impairment, I am satisfied Mr Ng will not become fit to stand trial within the next six months. Accordingly, I order that a special proceeding under subdivision 3 take place, as required by s 37(3) of the Act.

I certify that the preceding paragraph(s) comprise the reasons for decision of the District Court of Western Australia.
EO
Associate to Judge Astill
19 SEPTEMBER 2025