4 Clarifying the law on the defence of mental impairment

Introduction

  1. 4.1 The terms of reference ask the Commission to consider issues with regard to the defence of mental impairment. The Commission is asked to consider whether a definition of mental impairment should be introduced into the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997 (Vic) (‘CMIA’) and, if so, how it should be defined.
  2. 4.2 This chapter contains the Commission’s recommendations on this issue. These include recommendations that seek to clarify the law on the defence of mental impairment by:
  • introducing a statutory definition of mental impairment that comprises a non-exhaustive list of underlying conditions that ought to be included as a mental impairment with a focus on the underlying pathology of the condition rather than the source of the condition
  • changing the meaning of the second limb of the mental impairment test to be consistent with its application by clinicians and interpretation in case law.
  1. 4.3 The Commission also makes a recommendation to ensure that these changes to the defence of mental impairment are included in the Children, Youth and Families Act 2005 (Vic) under the expansion of the CMIA to the Children’s Court (see Chapter 6) to ensure the consistent application of the law to young people.1
  2. 4.4 Other issues in the terms of reference and supplementary terms of reference that relate to the defence of mental impairment examined by the Commission in this report include:
  • whether there should be an expansion of the orders available in the Magistrates’ Court after a finding of not guilty because of mental impairment (Chapter 5)2
  • whether there should be an expansion of the orders available in the Children’s Court after a finding of not guilty because of mental impairment (Chapter 6)
  • whether legislative clarification is required on how the law should provide for the jury to approach the elements of an offence and any defences or exceptions when the defence of mental impairment is in issue (Chapter 7).

 

Background

Criminal responsibility and the defence of mental impairment

  1. 4.5 For a person to be found guilty of an offence, it must be proved that the person committed both the physical elements and the fault elements of the offence:
  • Physical element (also referred to as the actus reus)—This element varies depending on the nature of the crime, but may include the conduct (for example, rape requires the sexual penetration of a person), circumstance (for example, rape requires the absence of consent) or cause (for example, murder causes the death of a person) to establish the crime.
  • Mental or fault element (also referred to as the mens rea)—This element describes the ‘fault’, which applies in relation to a physical element of an offence. The ‘fault’ usually refers to the state of mind of the accused and includes concepts such as intention, knowledge and recklessness.
  1. 4.6 The law has long recognised that a person should not be held criminally responsible if at the time of committing an offence, the person lacked the mental capacity to commit the offence because of a ‘mental impairment’. The defence of mental impairment is grounded in two important principles:
  • a mental impairment may act as an excuse from criminal responsibility
  • the community must be protected from people who, as a result of a mental impairment, are a risk to others.3
  1. 4.7 Under the current law in Victoria, this also includes consideration of the risk people pose to themselves.4

Development of the defence of mental impairment

  1. 4.8 In the Commission’s Review of the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997: consultation paper (‘the consultation paper’), it outlined the background to the current defence of mental impairment under the CMIA—previously called the ‘defence of insanity’.
  2. 4.9 While the principles underlying the insanity defence have been in existence for centuries, it was not developed as a legal doctrine until the early 1800s. The legal defence was formulated as a result of two English cases: R v Hadfield and Daniel M’Naghten’s Case.5
  3. 4.10 The case of R v Hadfield prompted the introduction of the Criminal Lunatics Act 1800, which allowed for people acquitted on the grounds of insanity to be kept in custody at the King’s pleasure.6 This legislation was later adopted in Australia and formed the basis for the ‘Governor’s pleasure’ regime.7

 

  1. 4.11 Daniel M’Naghten’s Case provided the requirements for establishing the common law defence of insanity. The court (House of Lords), provided the following explanation of the operation of the insanity defence:

jurors ought to be told that in all cases every man is to be presumed to be sane, and to possess a sufficient degree of reason to be responsible for his crimes, until the contrary be proved to their satisfaction; and that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of committing the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or, if he did know it, that he did not know he was doing what was wrong.8

  1. 4.12 In Victoria, these requirements known as the ‘M’Naghten rules’ provided the basis for the common law defence of insanity that existed under the Governor’s pleasure regime. These rules provide the ‘template for the defence of insanity in the criminal law of numerous jurisdictions’.9

The defence of mental impairment under the CMIA

  1. 4.13 The CMIA explicitly abrogated the common law defence of insanity and replaced it with the statutory defence of mental impairment.10 However, the concept of mental impairment and the statutory test for the defence of mental impairment under the CMIA remains the same as they were under the common law defence of insanity. In the second reading speech for the Crimes (Mental Impairment and Unfitness to Stand Trial) Bill 1997, the Attorney-General explained:

The term ‘insanity’ has been replaced by the term ‘mental impairment’ because the former term is antiquated and carries [a] historical stigma. However, it is important to note that the bill does not alter the existing criminal law in relation to determining criminal responsibility … The bill makes it clear that the new defence of mental impairment has the same meaning as the defence formerly known as the defence of insanity and is to be interpreted accordingly.11

  1. 4.14 Under current law in Victoria, the term ‘mental impairment’ means a ‘disease of the mind’.12 The M’Naghten elements of the defence were added to the statutory defence without any alteration.13 Thus, the changes made by the CMIA to the defence of mental impairment were largely changes in terminology and were not intended to affect the scope of the defence in practice.14
  2. 4.15 The defence of mental impairment is set out in section 20 of the CMIA. The defence is established if at the time of engaging in conduct constituting the offence, the person was suffering from a mental impairment that had the effect that:
  • the person did not know the nature and quality of the conduct, or
  • the person did not know that the conduct was wrong.
  1. 4.16 The CMIA provides that a person will not know that their conduct is wrong where they are unable to ‘reason with a moderate degree of sense and composure about whether the conduct, as perceived by reasonable people, was wrong’.15

Should mental impairment be defined in the CMIA?

  1. 4.17 The consultation paper asked questions about how the defence of mental impairment currently operates, and whether ‘mental impairment’ should be defined.

Current definition of mental impairment in Victoria

  1. 4.18 The term ‘mental impairment’ is not defined under the CMIA. Currently in Victoria,
    the common law is relied upon in determining what constitutes a mental impairment. In order for the defence of mental impairment to be established, a person must be ‘labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know
    he was doing what was wrong’ [emphasis added].16
  2. 4.19 This position was affirmed by the Victorian Supreme Court in the case of R v Sebalj (‘Sebalj’),17 in which it was held that ‘the term “mental impairment” should not be construed as changing the common law but construed as referring to the concept of
    “a disease of the mind” used in the common law defence of insanity’.18
  3. 4.20 In summary, the current requirements to establish the defence of mental impairment under the CMIA are:
  • that at the time of the commission of the offending conduct, a person has a mental impairment, characterised as a ‘disease of the mind’, and
  • that mental impairment had at least one of two effects:
  • the person did not know the nature and quality of their conduct, or
  • the person did not know that their conduct was wrong.

The meaning of ‘disease of the mind’ at common law

  1. 4.21 There has been much debate about which conditions constitute a disease of the mind for the purposes of the mental impairment defence and it has been argued that ‘[l]egal definitions of what constitutes a mental condition in the insanity defence are generally unclear and variable’.19
  2. 4.22 The Victorian Parliament Law Reform Committee’s report Inquiry into Access to and Interaction with the Justice System by People with an Intellectual Disability and their Families and Carers, acknowledged there is ambiguity in the meaning of the term ‘mental impairment’ and recommended that the term be defined in legislation.20
  3. 4.23 Recommendation 33 of that report proposed that the Victorian Government consider introducing legislation to provide a definition of ‘mental impairment’ that encompasses ‘mental illness, intellectual disability, acquired brain injuries and severe personality disorders’ while maintaining separate criteria for determining unfitness to stand trial.21
 
‘Disease of the mind’ and the defence of mental impairment
  1. 4.24 The definition of what constitutes mental impairment is a matter of law. Whether an accused suffered from a mental impairment at the relevant time is a matter of fact.22
  2. 4.25 The concept of ‘disease of the mind’ was outlined in the case of R v Radford,23 and approved in the case of R v Falconer24 (‘Falconer’), where it was stated:

The essential notion appears to be that in order to constitute insanity in the eyes of the law, the malfunction of the mental faculties called ‘defect of reason’ in the M’Naghten rules, must result from an underlying pathological infirmity of the mind, be it of long or short duration and be it permanent or temporary, which can be properly termed mental illness, as distinct from the reaction of a healthy mind to extraordinary external stimuli.25

  1. 4.26 Prior to Falconer, two different approaches were employed by the courts to determine what constitutes a ‘disease of the mind’, described as the ‘internal/external test’ and the ‘recurrence/continuing danger test’.26 These tests focussed on the characteristics of the condition itself. The external/internal test required a mental condition, to be classified as a ‘disease of the mind’, to have a cause that is internal to the accused, rather than an external cause.27 The recurrence/continuing danger test required a mental condition, to be classified as a ‘disease of the mind’, to have a tendency to recur.28
  2. 4.27 An important distinction made in the ‘sound/unsound mind’ approach in Falconer was that a ‘disease of the mind’ must result from an unhealthy mind reacting to extraordinary external stimuli rather than a healthy mind reacting to extraordinary external stimuli. This means that it is not the ‘extraordinary external stimuli’ itself or whether the condition is permanent, temporary or of long or short duration that determines whether a condition falls within the meaning of ‘disease of the mind’, but whether there is an ‘underlying pathological infirmity of the mind’.29
  3. 4.28 An example of how this approach has been applied is demonstrated by looking at cases involving intoxication. Historically at common law, intoxication leading to temporary insanity was regarded as sufficient to establish the defence.30 However, the common law, in cases such as Falconer, developed to distinguish between temporary states of mental impairment induced by intoxication (which did not constitute ‘insanity’ as there was no underlying pathological condition) and underlying diseases of the mind albeit caused by intoxication (which did constitute ‘insanity’).
  4. 4.29 While mental illness clearly falls within the common law meaning of ‘disease of the mind’ and thus within the scope of the defence of mental impairment, it remains unclear whether other conditions such as an intellectual disability or other cognitive impairment constitute a ‘mental impairment’.

 

  1. 4.30 In the consultation paper, the Commission identified examples where conditions have been stated to be ‘diseases of the mind’. They include:31
  • major mental illnesses such as schizophrenia32
  • brain injuries, tumours or disorders33
  • physical diseases that affect the soundness of mental faculties, such as cerebral arteriosclerosis.34
  1. 4.31 Conditions that have been stated not to be a ‘disease of the mind’ include, for example, concussion from a blow to the head35 or drug-induced psychosis.36 There is a lack of clarity as to whether cases of dissociation and epilepsy constitute a mental impairment.37
  2. 4.32 Underlying the ‘disease of the mind’ test is an attempt to draw a distinction between conditions that are the product of an unhealthy mind, either caused by natural or external events, and those that are the result that an external cause, either within or outside the control of the person, has on an otherwise healthy mind.
  3. 4.33 However, this distinction can have disparate outcomes when applied in practice, as demonstrated by Sebalj.38 Sebalj was charged with murder committed while he was in a psychotic state that occurred after withdrawal from heroin and amphetamines. A preliminary ruling was sought on the meaning of the term ‘mental impairment’. It was held that the term ‘mental impairment’ should be interpreted as referring to the common law term ‘disease of the mind’. In doing so, Justice Smith had regard to the CMIA provisions, the intention of parliament in introducing the term ‘mental impairment’ in the CMIA and the effect that broadening the term mental impairment to include short-term or transient conditions may have—namely to ‘apply wherever the mind of a person charged with an offence had been adversely impaired to a material degree by alcohol or other drugs’.39 As Sebalj’s psychosis was a ‘temporary’ condition connected with the use of substances—withdrawal from drugs—his mental condition was ‘drug-induced’ and not a disease of the mind. Sebalj was subsequently convicted and sentenced to 15 years’ imprisonment.40 After Sebalj’s plea but before being sentenced, he had developed symptoms of schizophrenia.41
‘Disease of the mind’ and the doctrine of automatism
  1. 4.34 The common law term ‘disease of the mind’ is also relevant to the doctrine of automatism. Automatism is a legal term that refers to acts committed without volition and ‘implies the total absence of control and direction by the accused’s will’.42
  2. 4.35 There are two types of automatism:
  • sane automatism
  • insane automatism.
  1. 4.36 The distinction between sane and insane automatism is based on the sound/unsound mind test outlined above at [4.27].43 This distinction has serious implications for the accused because if successful in meeting the requirements of sane automatism, the accused will be wholly acquitted. For an accused who meets the requirements of insane automatism, however, the defence of mental impairment applies. If successful, the accused will be found not guilty because of mental impairment and could be made liable to supervision and placed on a supervision order.
  2. 4.37 Insane automatism includes mental conditions that result from a ‘disease of the mind’ and are the reaction of an unsound mind to its own delusions or to external stimuli.
  3. 4.38 Sane automatism includes conditions solely caused by external stimuli and as such does not result from a ‘disease of the mind’.44 An underlying infirmity triggered by external stimuli, however, will still be considered a ‘disease of the mind’ and could thus give rise to a defence of insane automatism.
  4. 4.39 The sound/unsound mind test under the doctrine of automatism has also resulted in disparate outcomes from a policy point of view. For example, insane automatism has been held to arise where a person is hyperglycaemic due to excessive blood sugar levels because it is considered an underlying infirmity and thus a ‘disease of the mind’.45 However, where a person is hypoglycaemic due to excessive insulin intake, this is considered to be caused by an external factor, not a ‘disease of the mind’, and sane automatism applies.46

Application of the defence in Victoria under the current definition

  1. 4.40 Analysis of the 159 cases dealt with under the CMIA in the higher courts from 1 July 2000 to 30 June 2012 suggests that mental illness is the most prevalent form of mental condition raised as a basis for establishing the defence of mental impairment.
  2. 4.41 Of the 159 cases, judgments were available in 65 cases (40.9 per cent). Of these 65 cases, the defence of mental impairment was raised in 46 cases.47
  3. 4.42 Table 1 shows the mental conditions in the 46 cases where the defence of mental impairment was raised.

 

Table 1: Mental condition where defence of mental impairment raised, CMIA cases in higher courts, 2000–01 to 2011–12 4849

Table 1: mental condition where defence of mental impairment raised

Source: Sentencing Advisory Council, higher courts sentencing database

 

The definition of mental impairment in other jurisdictions

  1. 4.43 In other jurisdictions, the definition of mental impairment includes mental illness, intellectual disability and cognitive impairment while conditions such as personality disorders and those related to the temporary effects of ingesting substances are sometimes specifically excluded from the definition. Appendix E contains a comparison of the legislative definition of mental impairment in Australian jurisdictions, along with New Zealand, Scotland, the United Kingdom and Canada. Apart from New South Wales, all other Australian jurisdictions provide some definition of mental impairment.
  2. 4.44 The Commonwealth and the Australian Capital Territory both adopt the Model Criminal Code, which provides for a definition of mental impairment that includes personality disorders.50 The Northern Territory and South Australia also adopt the Model Criminal Code, but do not include personality disorders in the definition of mental impairment.51
  3. 4.45 In May 2013, the New South Wales Law Reform Commission released its report People with Cognitive and Mental Health Impairments in the Criminal Justice System: Criminal Responsibility and Consequences.52 The report recommends adopting a definition of mental impairment that includes a volitional element. The recommended definition of mental impairment includes but is not limited to the following conditions: mental health disorders (including independent substance-induced mental disorders); cognitive impairments (intellectual disability, borderline intellectual functioning, dementias, acquired brain injury, drug- or alcohol-related brain damage, autism spectrum disorders); but excludes personality disorders.53

 

  1. 4.46 The South Australian Sentencing Advisory Council has also considered this issue and released a discussion paper in July 2013 on the defence of ‘mental incompetence’. The paper asks whether amendments should be made to the definition of mental impairment that is outlined in section 269A of the Criminal Law Consolidation Act 1935 (SA) and has proposed four possible options.54 These include extending the definition of mental impairment beyond impairments resulting from mental illness, intellectual disability or senility, and various options excluding certain conditions in combination with a mental impairment, such as voluntary intoxication and habitual use of intoxicants.55

Views in submissions and consultations

Should the CMIA define mental impairment?

  1. 4.47 The majority view in submissions and consultations was that the term ‘mental impairment’ should be defined in the CMIA. The main reasons provided in support of a definition of mental impairment were the inadequacy or inappropriateness of the current common law phrase ‘disease of the mind’56 and to improve consistency in the application of the defence of mental impairment.57
  2. 4.48 Some submissions suggested that the uncertainty as to what constitutes a mental impairment can lead to inconsistencies in the application of the mental impairment defence.58 The Australian Clinical Psychology Association supported this view:

In practice this [mental impairment being undefined] can lead to an inconsistent understanding and unfair application of this term in legal proceedings. … We would recommend that a statutory definition of mental impairment is included in the legislation to ensure the term is applied appropriately, consistently and fairly. Where terms have been left undefined there is more room for inconsistency, for individual interpretation and application of that term leading to greater inconsistencies and unfairness.59

  1. 4.49 This view was also supported by the Office of Public Prosecutions, which stated that ‘there is considerable uncertainty as to what other conditions, if any, constitute a “disease of the mind” or mental impairment. … There is therefore inconsistency in the application of the test’.60
  2. 4.50 The Victorian Institute of Forensic Mental Health (Forensicare) did not support the introduction of a definition of mental impairment and was of the view that the current common law formulation of ‘disease of the mind’ was appropriate.61 Forensicare suggested that a definition would not provide clarity in this area of law and that ‘[s]uch a consideration is complex, multifaceted and must be examined on a case by case basis’.62

 

An inclusive definition of mental impairment

  1. 4.51 A number of submissions expressed support for the development of a broad and
    inclusive definition of mental impairment.63 For example, Victoria Legal Aid suggested
    the following:

Inserting an inclusive definition in the Act would be consistent with the intention of the Act (which currently contemplates intellectually disabled people and the involvement of disability service providers and the Departments of Health and Human Services) and would reflect clearly how the Act generally operates in practice [citation omitted].64

  1. 4.52 This view was also supported by the Criminal Bar Association, which proposed that any definition of mental impairment should be inclusive and flexible:

Medicine, psychiatry, and psychology, along with numerous other fields of science, are constantly developing. The Act should permit the law to embrace developments in this respect, with appropriate safeguards. To do otherwise risks the law falling behind, unfairness in an individual case and the justice system coming into disrepute.65

  1. 4.53 In considering how mental impairment should be defined, stakeholders recommended that any definition should not be based on diagnostic criteria, arguing that classification systems such as the Diagnostic and Statistical Manual of Mental Disorders (DSM) are subject to change or are not designed for medico-legal purposes.66 Clinical diagnoses may be controversial.67 Further, ‘mental impairment’ involves a consideration of complex issues concerning related impairments.68
  2. 4.54 The Chief Psychiatrist suggested that, if any definition of mental impairment were to be proposed, emphasis should be placed on the functional consequences of a disorder as opposed to the nature of the disorder itself.69 This view was supported in a submission by Jamie Walvisch who argued that ‘it should be made clear that the cause of the impairment (for example, whether it is internally or externally caused) is not important – that the test is solely focussed on whether the accused suffered from an abnormal mental state’.70

Mental conditions that should be included in the definition

  1. 4.55 The Office of Public Prosecutions recommended that a definition include ‘all major known conditions (that are not self-induced)’.71
  2. 4.56 Victoria Legal Aid proposed an inclusive definition of mental impairment that includes but is not limited to ‘psychiatric illness, intellectual disability and cognitive and neurological impairments’.72 This view was supported by the Law Institute of Victoria, which recommended that:

the CMIA provide an extensive definition of mental impairment which includes a wide range of disabilities, including cognitive disabilities such as intellectual disabilities, learning disabilities, acquired brain injuries, and degenerative disabilities as well as psycho-social disabilities. However, we submit that this should not limit the Court’s discretion as to what else might be included in the definition.73

 

  1. 4.57 There was support for the inclusion of intellectual disability in a definition of mental impairment.74 The Law Institute of Victoria suggested that the common law term ‘disease of the mind’ is inadequate in capturing the range of cognitive impairments.75 The Victorian Equal Opportunity and Human Rights Commission shared this view, arguing that a definition that encompasses ‘current understandings of cognitive disabilities (including intellectual, learning, acquired and degenerative disabilities)’ is required.76
  2. 4.58 The Progressive Law Network supported the inclusion of mental illness, intellectual disability, acquired brain injury and severe personality disorder.77
  3. 4.59 Forensicare raised concerns about resources if there was a significant expansion of the conditions currently constituting a ‘disease of the mind’. It argued that ‘[t]he capability of the service system to safely manage large numbers of offenders within current resource levels is an important consideration’.78 In addition to not supporting the introduction of a definition, Forensicare did not support the inclusion of personality disorders, acquired brain injuries and substance-induced psychosis disorders in any definition, as their inclusion would significantly strain existing resources.79
  4. 4.60 Consultant forensic psychiatrists shared Forensicare’s concern with respect to the inclusion of personality disorders, with one psychiatrist stating that if the definition of ‘disease of the mind’ was expanded to include personality disorders, it would be hard to find an offender in the state who did not ‘squeeze into this’.80 In his submission to the Commission, Associate Professor Andrew Carroll also expressed concerns about ‘net-widening’, particularly in relation to personality disorders:

I would be very concerned with any expansion into personality disorder: the limits on this are far from clear; a more useful approach would be to specifically exclude cases where the only diagnosable mental disorder is a personality disorder. … The reality is that any such expansion of the concept of disease of the mind would result in many CMIA patients residing in prisons and/or would result in non-mentally ill patients occupying beds [at] Thomas Embling Hospital, a facility which is ill-equipped to manage severe personality disorder in the absence of mental illness.81

  1. 4.61 Associate Professor Carroll also identified the difficulties that can arise in distinguishing cases of self-induced psychotic disorders from drug-induced psychoses:

There are some boundary issues around drug associated psychoses, particularly for example when people with established psychotic illnesses intentionally abuse substances and therefore become acutely psychotic. It is very difficult to establish clear boundaries in these matters …82

It was therefore suggested that guidelines would need to be developed if these conditions were to be included in the definition of mental impairment.

 

The Commission’s conclusion

The need to clarify the law

  1. 4.62 The Commission agrees that the law is unclear about which conditions constitute a ‘disease of the mind’, and that this may be affecting the consistency of the application of the defence of mental impairment and may result in disparate outcomes.
  2. 4.63 The Commission acknowledges Forensicare’s view that the current approach regarding ‘disease of the mind’ works well in practice and allows the complexities of each matter to be considered on a case-by-case basis. However, due to the overwhelming support in submissions and consultations for a definition of mental impairment and the Commission’s view that a definition will assist to clarify the law, the Commission recommends a definition of mental impairment be introduced into the CMIA.
  3. 4.64 The proposed definition of mental impairment therefore aims to clarify the law by outlining the types of conditions that are included as a mental impairment and those that are excluded, while ensuring there is flexibility in the definition to allow for consideration of complex or difficult cases. In introducing a definition of mental impairment, the Commission emphasises that the mere presence of a particular condition will not entitle the accused to a finding of not guilty because of mental impairment—the condition
    must have been present at the time of the offence and be of such severity as to satisfy the operational aspect of the test in terms of its effect on a person’s mental functioning and capacity.

A broad and inclusive definition of mental impairment

  1. 4.65 The Commission is of the view that the best approach in clarifying the law on the meaning of ‘mental impairment’ is to introduce a broad and inclusive definition that is limited by the operational elements of the defence of mental impairment.
  2. 4.66 The proposed definition will provide flexibility to include any mental condition (subject to specific exclusions) that has the effect of the accused not knowing the nature and quality of their conduct and/or not knowing their conduct is wrong.
  3. 4.67 The Commission is of the view that a broad definition will not open the floodgates for people claiming the defence of mental impairment. This is because the scope of the defence will be limited by the high standard required in meeting the operational elements of the defence,83 and the serious consequences of a successful defence in the imposition of an indefinite supervision order.
  4. 4.68 In its final report on defences to homicide in 2004 the Commission recommended a definition of mental impairment that includes but is not limited to the common law notion of a ‘disease of the mind’.84 The reasoning for this recommendation was that the ‘disease of the mind’ formulation did not provide enough flexibility and had resulted in interpretations of the term that were ‘unnecessarily narrow.’ In doing so, the Commission looked to the purpose of the defence of mental impairment:

If the purpose of the defence is to ensure that people are excused from criminal responsibility when their cognitive functions are so affected that they are unable to understand what they are doing or that it is wrong, then it should not matter what the cause of the particular impairment was.85

 

  1. 4.69 The same view underpins the recommendation made in the present report to introduce a statutory definition of mental impairment. The Commission considers that a definition of mental impairment should include but not be limited to the common law notion of a ‘disease of the mind’. It is therefore not intended that the conditions currently considered a ‘disease of the mind’ be excluded from the proposed statutory definition of mental impairment.

Self-induced conditions that are connected with substance use

  1. 4.70 The Commission is of the view that there are some conditions that should not be included in the definition of mental impairment.
  2. 4.71 For sound public policy reasons, the Commission supports a definition that distinguishes between two types of conditions that are self-induced and connected with the effect of ingesting substances:
  • Self-induced conditions that result from the temporary effects of ingesting substances—These conditions should be excluded from the definition of mental impairment. An example of this is a person who ingests alcohol or drugs where the resulting intoxication is temporary and no longer exists once the alcohol or drugs have left the person’s system.
  • Self-induced independent conditions resulting from ingesting substances—These conditions should be included in the definition of mental impairment. An example of this is a person who several years earlier, chronically abused alcohol, which resulted in an acquired brain injury. This condition should be included in the definition because the acquired brain injury exists independently of the ingestion of substances, and would remain after the person was no longer abusing alcohol. Another example is a person who experiences psychosis after ingesting drugs, where the psychosis is present after the drugs have left the person’s system.
  1. 4.72 To include self-induced conditions that result from the temporary effects of ingesting substances in the definition of mental impairment would dramatically widen the definition in a manner that is inconsistent with its underlying policy. For these conditions, there is no underlying pathology and the impairment is solely referable to the effect of a substance that the accused has self-administered. To include these conditions within the definition would undermine the purpose of the defence by extending it to people who commit offences who are responsible for the temporary impairment of their mental faculties through the ingestion of substances.
  2. 4.73 The inclusion of self-induced independent conditions resulting from ingesting substances in the definition of mental impairment advances the reasoning outlined in the Commission’s 2004 Defences to Homicide final report. The Commission continues to hold the view that if a person is suffering from a mental condition that impairs the person’s functioning to such an extent that they do not know the nature and quality of what they are doing or whether it is wrong, the fact that the source of that underlying condition is external should not exclude the availability of the defence.86 The Sebalj case, discussed at [4.33], was provided in the Commission’s report on defences to homicide as an example of a case that should be included in the definition.
  3. 4.74 The Commission acknowledges that these cases can be very complex and in some circumstances it will be difficult to determine whether a person’s actions were because of a mental condition or due to the effects of ingesting substances, as many people with a history of mental illness also have a history of substance use.87 For example, there may be circumstances where a person started ingesting substances when they were young, subsequently developed psychotic symptoms that remained after the substances had left the person’s system, and then started ingesting substances again at the time of committing the conduct constituting the offence. In these circumstances it would be difficult to determine if, at the time of the offending conduct, the accused was suffering from the temporary effects of substance use or a permanent condition connected with previous substance use.
  4. 4.75 Research has also shown that it is often ‘not possible to distinguish substance-induced psychosis from a first-episode psychosis in the context of a primary mental health disorder due to the very high level of comorbidity’.88 For example, a person may ingest drugs for the first time and under the influence of the drug experience psychotic symptoms that resolve for a short period, prior to the person developing an independent condition that persists in the absence of further drug use.
  5. 4.76 Courts will therefore be heavily reliant on expert evidence in difficult cases in applying the definition to the individual circumstances of the case, and conditions would be included or excluded based on the latest expertise in the relevant field. Cases that involve disentangling the temporary effects of substances and ongoing conditions connected with substance use will also require thorough and detailed clinical assessments by experts to ensure a proper evaluation of the applicability of the definition. It has been argued in relation to the law in England and Wales that:

A clinical evaluation that will be of use to the court will require a thorough history of the events, with a special focus on the defendant’s account of the event and consumption of intoxicants in the period leading up to the offence. … It is also essential to thoroughly tease out the history of alcohol and substance misuse.89

Recommendation

24 The Crimes (Mental Impairment and Unfitness to be Tried) Act 1997 (Vic) should be amended to insert a provision in section 20 of the Act that defines a ‘mental impairment’ for the purposes of the defence as a condition that ‘includes, but is not limited to, mental illness, intellectual disability and cognitive impairment’.

The proposed definition of mental impairment should not include any self-induced temporary conditions resulting from the effects of ingesting substances.

The proposed definition should include self-induced conditions that exist independently of the effect of ingesting substances.

 

  1. 4.77 The recommended definition is consistent with the approach recently recommended by the New South Wales Law Reform Commission (NSWLRC), as follows:

The proposed definition of mental health impairment … includes “substance induced mental disorders” … [defined as] ongoing mental health impairments such as drug-induced psychoses, but excludes substance abuse disorders (addiction to substances) or the temporary effects of ingesting substances.90

 

  1. 4.78 The NSWLRC also noted that such a definition has the same effect as that contained in Commonwealth, Northern Territory and Australian Capital Territory provisions. The definition of mental illness in the Criminal Code Act 1995 (Cth) excludes conditions that are caused by external stimuli but qualifies this by saying that ‘such a condition may be evidence of a mental illness if it involves some abnormality and is prone to recur’.91
  2. 4.79 However, the NSWLRC also noted the concerns that have been recently been expressed in Queensland in distinguishing between temporary and independent states in cases under the Criminal Code Act 1899 (Qld) where the insanity defence has been raised by accused charged with offences committed under psychosis following the use of amphetamines.92
  3. 4.80 The proposed definition of mental impairment will accordingly require careful treatment and consideration by Victorian courts if it is implemented. The Commission also considers that the development of guidelines, as suggested in submissions, could assist experts in making assessments and providing reports to the court in light of the Commission’s proposed changes.

Implications of the Commission’s recommendations

  1. 4.81 While it is beyond the scope of this review, the Commission notes that any changes to the definition of mental impairment may have implications for the doctrine of automatism. As discussed at [4.34]–[4.39], the term ‘disease of the mind’ and the sound/unsound mind test are currently used to distinguish between sane and insane automatism. This distinction will no longer apply if the definition of mental impairment is changed from a disease of the mind to an inclusive definition recommended by the Commission. This may affect the process for distinguishing between cases of sane and insane automatism.
  2. 4.82 Another possible implication is that a broad and inclusive definition of mental impairment may mean that a condition that was previously classified as sane automatism would now fall within the definition of mental impairment. The effect of this is that an accused who was previously entitled to an acquittal for sane automatism, may now be found not criminally responsible, be declared liable to supervision and be placed on a supervision order under the CMIA.

The test for establishing the defence of mental impairment

  1. 4.83 The test for establishing the defence of mental impairment is contained in the CMIA,
    as follows:

The defence of mental impairment is established for a person charged with an offence if, at the time of engaging in the conduct constituting the offence, the person was suffering from a mental impairment that had the effect that—

(a) he or she did not know the nature and quality of the conduct; or

(b) he or she did not know that the conduct was wrong (that is, he or she could not reason with a moderate degree of sense and composure about whether the conduct, as perceived by reasonable people, was wrong).93

  1. 4.84 In the consultation paper, the Commission explained these two limbs of the test for the defence of mental impairment and sought views on how the defence operates in practice. The Commission asked detailed questions on whether the operational elements of the defence should change if a definition of mental impairment were introduced and whether there were issues with the interpretation of the phrase in the second limb of the test that a person ‘reason with a moderate degree of sense and composure’.

The two limbs of the test

  1. 4.85 The two limbs of the test are known as the ‘operational elements’ of the defence. The first limb of the test focuses on the nature and quality of the act itself, for example, the physical nature of the act or the consequences of the act. This is discussed in more detail in Chapter 7 at [7.123]–[7.128]. In considering the practical operation of the defence, cases in which an accused does not know the nature and quality of their conduct are rare.
  2. 4.86 It is far more common for the defence of mental impairment to be established on the second limb of the M’Naghten test. This limb relates to the way in which the person processes knowledge about the nature and quality of their conduct, in terms of whether it is wrong.94
  3. 4.87 A study by the South Australian Sentencing Advisory Council estimates approximately 87 per cent of all findings of ‘mental incompetence’ are based on the second limb of the test, that the accused did not know that their conduct was wrong; while 2 per cent of all mental impairment defences are based on both limbs of the test.95
  4. 4.88 This is supported by anecdotal information obtained during consultations, as well as an informal analysis of the 159 cases dealt with under the CMIA in the higher courts from 1 July 2000 to 30 June 2012. There were judgments available in 65 cases (40.9 per cent) from which detailed information about the case could be gleaned. Of these, in 41 cases the accused was found not guilty because of mental impairment. In 18 of these cases there was information to indicate the basis of the finding, and in none of these 18 cases was the finding made on the basis of the first limb alone.96

Issues with the second limb of the test—requirement to ‘reason with a moderate degree of sense and composure’

  1. 4.89 The CMIA outlines the standard to be applied in considering whether the accused knew that their conduct was wrong, and incorporates the phrase ‘that is, he or she could not reason with a moderate degree of sense and composure about whether the conduct, as perceived by reasonable people, was wrong’.97
  2. 4.90 The consultation paper outlined the view of the New South Wales Law Reform Commission (NSWLRC) in relation to the Victorian approach to the defence of mental impairment. In particular, the requirement that the person be unable to consider their actions with some degree of composure and reason was questioned, with the NSWLRC suggesting that it is ‘the extinction or impairment of subconscious regulation, not an inability to reason calmly’ that explains the act of the accused.98
  3. 4.91 Despite these comments, in its recent review the NSWLRC recommended retaining both elements of the M’Naghten test. The NSWLRC also recommended the addition of the wording from section 20(1)(b) of the CMIA.99 This wording was chosen in preference to defining the test in terms of a person lacking ‘capacity to know’.

 

  1. 4.92 The majority of Australian jurisdictions include a volitional element in the definition of mental impairment.100 A volitional element adds a requirement to the defence of mental impairment that the accused was unable to control their conduct.101 One of the main arguments against inclusion of a volitional element has been that it is difficult to establish on the evidence that a person was unable to control their conduct.102
  2. 4.93 The NSWLRC recommended inclusion of a volitional element in their defence to be consistent with other Australian jurisdictions, reasoning that it is ‘appropriate to provide for the exculpation of those defendants who, because of cognitive or mental health impairments, genuinely could not control their actions’.103
  3. 4.94 In the Commission’s 2004 Defences to Homicide final report, it did not recommend changes to the test for the defence of mental impairment, given the overwhelming view in submissions and consultations that the defence was working well in practice and was ‘well understood and appropriately applied’.104 In coming to this decision, the Commission also considered that at the time of the review, the CMIA had only been in operation for a relatively short time and that ‘[t]o change the legislation so soon after its introduction without clear evidence of a need to do so would be inappropriate’.105 The Commission therefore recommended that the Department of Human Services and the Department of Justice monitor the CMIA and continue to assess how the defence was operating in practice.
  4. 4.95 The Commission’s report also stated that there was not sufficient evidence to recommend the inclusion of a volitional element in the defence. The report outlined that submissions from those involved in the practical operation of the defence argued that the current formulation was sufficiently flexible to allow some of those people who were unable to control their conduct to qualify for the defence, where they also met the other requirements of the test.106

Views in submissions and consultations

  1. 4.96 Forensicare recommended there be no change to the operational elements of the defence of mental impairment.107 While two submissions referred to a volitional element that is part of the defence in other Australian jurisdictions, no one supported the introduction of a volitional element to the defence in Victoria.108 Forensicare explained that:

introducing a volitional element into the test is unnecessary and may bring with it its own set of interpretive issues. This is because an accused who commits an offence whilst mentally impaired is often able to control their conduct but, for example, may feel morally compelled to commit the act.109

  1. 4.97 One submission argued for the ‘reasons-responsiveness’ approach where an accused should only be provided with a defence where ‘they are not capable of recognising and responding to the reasons that bear on his or her situation’.110

 

  1. 4.98 In relation to the second element of the defence, the consultation paper asked whether the phrase ‘reason with a moderate degree of sense and composure’ required clarification. While this was not an issue identified by members of the legal sector, clinicians were generally of the view that clarification is required as there is no common understanding of the meaning of ‘moderate degree of sense and composure’.111
  2. 4.99 A number of consultant forensic psychiatrists also raised concerns during a consultation about the meaning of the phrase ‘moderate degree of sense and composure’.112 One participant commented that ‘[m]ost people are not acting with a moderate degree of sense and composure. There is a real problem with those words.’ Another participant said that ‘[t]he wording is essentially meaningless’. A third participant questioned whether there would be a consensus around the table of clinicians as to the meaning of the term, stating that ‘[i]t is very subjective’ and that ‘the level of agreement on the meaning around the table would not be high’. As one participant explained, ‘[r]easonable is a very subjective judgment from an expert’s view.’
  3. 4.100 Associate Professor Andrew Carroll also questioned the subjectivity of the term ‘moderate degree of sense and composure’, arguing that:

The problem of course with the term ‘moderate degree of sense and composure’ is that there is very poor interrater reliability as to how ‘moderate’ is measured. In practice, this addition to the [M’Naghten] criteria can be used to argue for those who lack impulse control for any reason. Thus far, this has not resulted in any greater number of problematic cases but the vagueness of this term is surely undesirable.113

  1. 4.101 One person in consultations questioned whether any modification to this phrase would unnecessarily limit the defence. They noted that if the words ‘moderate degree of sense and composure’ were removed, many people would not be able to establish the mental impairment defence.114

The Commission’s conclusion

  1. 4.102 To establish whether an accused knows that their conduct is wrong, they must have understood it was wrong according to the principles of the reasonable person115 or be aware that reasonable people would ‘disapprove as wrong the actions he is performing’.116 While the test is focussed on what reasonable people would consider as wrong, rather than what is legally or morally wrong,117 the comprehension of a person ‘as to whether [their] actions were morally or legally wrong is not irrelevant to the evaluative task’.118

 

  1. 4.103 In the recent decision of Kosian v The Queen119 (‘Kosian’), a bench of the Victorian Court of Appeal120 observed that section 20(1) requires an ‘evaluation … of how the [mental impairment] affected the offender’s reasoning capacity, his understanding of what would be “wrong” and whether that understanding accorded with reasonable standards’.121 The issue in Kosian was whether an accused’s awareness about whether reasonable persons would consider his or her actions wrong can be informed by his or her capacity to appreciate the legal and moral consequences of his actions, a proposition that the Court of Appeal accepted.122 Whether evidence to the latter effect is relevant will turn on whether it gives insight into the former: Kosian ‘regarded himself as morally justified in killing the two victims, and assumed that his actions would be vindicated after a period of time’.123
  2. 4.104 In considering what is meant by the term ‘to reason with a moderate degree of sense and composure’, the clinicians who were involved as expert witnesses in Kosian referred to ‘reasoning capacity’,124 ‘thinking capacity’125 or explained that the accused is unable to ‘think rationally’.126 For example, in its judgment, the Court of Appeal referred to the evidence provided in re-examination, in which one of the experts was asked the question and responded as follows:

What is it about this man that prevented him from reasoning with a moderate degree of sense and composure about the wrongness of his act as perceived by reasonable people? … The simple answer to that is that he’s suffering from a mental illness called schizophrenia and we know that his thinking capacity is impaired simply because he’s prone to these deluded ideas. By definition, he can’t think rationally.127

  1. 4.105 The Commission agrees that being able to ‘reason with a moderate degree of sense and composure’ is about a person’s ability to think in a rational way about whether reasonable people would perceive their conduct to be wrong.
  2. 4.106 While the Commission has decided against amending the criteria for unfitness to stand trial to include a measure of ‘rationality’ in decision making or performing certain functions, the Commission’s view is that it is appropriate to use this term in this different context. The focus of the test for the defence of mental impairment is on an accused’s capacity to have an awareness of their own behaviour, either in assessing its physical nature and consequences and/or in terms of assessing whether other ‘reasonable’ people would consider it to be wrong. The use of the word rational in regard to this second limb of the test is appropriate, as it is consistent with the standard actually being applied by experts in assessing an accused’s ability to reason with the requisite standard of sense and composure about how reasonable people would view their behaviour. In light of the input received about the subjectivity of the current terms ‘reasonable’ and ‘moderate’ and lack of clarity of the phrase, the Commission considers that the concept of rationality will assist in this context.
  3. 4.107 The Commission does not recommend any changes to the essential elements of the two limbs of the mental impairment defence but recommends changes to the test for assessing whether a person knows their conduct is wrong.
  4. 4.108 The Commission agrees with the view expressed by clinicians in submissions and consultations that the phrase ‘to reason with a moderate degree of sense and composure’ requires clarification. The Commission’s recommendation therefore seeks to clarify the meaning of the second limb of the defence of mental impairment only.

Recommendation

25 Section 20(1)(b) of the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997(Vic) should be amended to replace ‘that is, he or she could not reason with a moderate degree of sense and composure about whether the conduct, as perceived by reasonable people, was wrong’ with ‘that is, he or
she did not have the capacity to think rationally about whether the conduct,
as perceived by reasonable people, was wrong’.

 

Application of the defence of mental impairment in the
Children’s Court

  1. 4.109 In the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997 and the Children’s Court of Victoria: supplementary consultation paper (‘the supplementary consultation paper’), the Commission asked about the applicability of the defence of mental impairment to young people and, in particular, how the law of doli incapax and the defence of mental impairment should interact in practice in establishing the mens rea for young people. In considering whether mental impairment should be defined as it relates to young people, the Commission sought views on how particular mental conditions affect young people and how this should be factored into the question of a possible definition of mental impairment for young people.

The doctrine of doli incapax

  1. 4.110 In Victoria, children under the age of 10 years are doli incapax (incapable of crime).
  2. 4.111 The Children, Youth and Families Act 2005 (Vic) (‘CYFA’) provides that it is conclusively presumed that a child under the age of 10 years cannot commit an offence.128
  3. 4.112 The definition of ‘child’ in the CYFA includes:

in the case of a person who is alleged to have committed an offence, a person who at the time of the alleged commission of the offence was under the age of 18 years but of or above the age of 10 years.129

  1. 4.113 Young people between 10 and 14 years of age are presumed to be doli incapax, but the presumption is subject to rebuttal.130 Although abolished in England,131 the presumption has been strongly affirmed in Victoria, notably by the Court of Appeal in R v ALH.132
  2. 4.114 The onus lies on the prosecution to prove not only the elements of the offence charged, but also that the child was doli capax—capable of crime.133

 

  1. 4.115 While doli incapax is a separate inquiry to that of the defence of mental impairment, similar questions are posed in considering the operational elements of the defence regarding the knowledge and wrongness of the conduct. The potential overlap between doli incapax and the defence of mental impairment is discussed in the case of R v ALH,134 where the presumption was reframed as an extension of mens rea:

Further, I consider that the traditional notion of presumption is inappropriate. I consider that the better view is that the prosecution should prove beyond reasonable doubt, as part of the mental element of the offence, that the child knew the act or acts were seriously wrong. Such a requirement is consonant with humane and fair treatment of children. It is part of a civilised society.135

The defence of mental impairment and young people

  1. 4.116 In the Children’s Court, the defence of mental impairment may be raised in relation to offences within the Children’s Court jurisdiction.136 The defence uses the same statutory test that applies in the higher courts.137

Approaches in other jurisdictions

  1. 4.117 In most other jurisdictions, the defence of mental impairment is the same for both adults and children when applied in the higher courts.138 Concerns have been expressed that the defence of mental impairment does not adequately take into account mental health conditions that affect young people.139 Detecting mental illness in young people can be problematic, as the symptoms are often still developing and treatment history may be limited or non-existent.140 There is also some confusion about the interplay between the defence of mental impairment and doli incapax.141 There is no publicly available data on the prevalence of the mental impairment defence for children; however, anecdotal evidence suggests that the defence of mental impairment is only used rarely for children in Victoria.
  2. 4.118 The Law Commission of England and Wales is currently conducting a review of the defence of mental impairment. In its discussion paper, the Law Commission summarised the view of stakeholders that the test for the defence of mental impairment should be
    the same for children.142
  3. 4.119 The Law Commission has also suggested that further consideration be given to developing a new defence of developmental immaturity.143 This defence would retain the same requirements of the test for the defence of mental impairment in relation to capacity but it would not require a recognised medical condition. Instead, something such as a learning disability that the accused may grow out of could be used to qualify for the defence.144 The creation of this defence is designed to address the problems faced by many young people who do not necessarily have a diagnosed mental impairment. This defence would not necessarily be restricted to people under the age of 18 years.145 In its previous review of the defence of diminished responsibility, the Law Commission recommended that developmental immaturity be introduced as a special category of the defence.146 The government rejected this recommendation.147
  4. 4.120 A defence of developmental immaturity would arguably be of more relevance in the United Kingdom because the doctrine of doli incapax has been abolished.148 However, while individuals aged under 14 years of age would be more likely to use the test, it could still be used by those aged 15 years and over.
  5. 4.121 Also relevant to the debate of these issues in the United Kingdom is the particular
    political climate following the James Bulger case. This is evidenced by the reporting in the local media of the public opposition to reforms that would reduce the criminal responsibility of children.149

Views in submissions and consultations

  1. 4.122 There was a recognition of doli incapax as a separate inquiry to the defence of mental impairment.150 In light of this and the scope of the review, the Commission does not propose any changes to that area of the law.
  2. 4.123 The majority view in submissions and consultations on the supplementary terms of reference was similar to the views put forward on the terms of reference, demonstrating support for a definition of mental impairment to provide clarity in the law. The Criminal Bar Association also supported having the same definition of mental impairment for both adults and young people.151
  3. 4.124 The Victorian Equal Opportunity and Human Rights Commission explained that in applying the definition or the defence of mental impairment, the developmental stage of the young person must be taken into account:

The formulation of any definition as it relates to children and young people must take into account that cognitive and mental health impairments in children and young people may differ from those of adults because young people’s cognitive abilities are still developing or it may be that a mental illness is emerging.152

  1. 4.125 The expertise of the person conducting the assessment was stated in submissions as being crucial to ensuring the defence is applied appropriately to young people. The Australian Clinical Psychology Association argued that:

Children are developing beings and as such it is important to understand the social, cognitive, emotional, behavioural and educational development of the child in the context of their family as well as in their broader social environment. Variability in the development of each of these areas is greater the younger the age of the child and all areas impact on the child’s ability to function regardless of their intellectual capacity.

We suggest that professionals with expertise in child development, for example, clinical psychologists, clinical neuropsychologists and child psychiatrists should be called upon to assess these areas to determine the severity of functional impairment.153

 

  1. 4.126 In considering the complexity in assessing young people with a mental impairment, one judge of the County Court of Victoria was of the view that flexibility in the definition of mental impairment is paramount.154 The Australian Psychological Society was also of the view that a flexible definition of mental impairment is important, arguing that:

Even if some conditions are incorporated into a definition of mental impairment, the determination of mental impairment in young people is complex and will need to be considered on a case-by-case basis.155

  1. 4.127 Most submissions and consultations did not express a view on whether changes should be made to the operational elements of the defence of mental impairment. However, one clinician raised concerns about the applicability of the phrase ‘reason with a moderate degree of sense and composure’ contained in section 20(1)(b) of the CMIA. Dr Adam Deacon was of the view that:

A young person with intellectual disability could arguably have less capacity to self-regulate. … There is also a group of adolescents who have suffered severe abuse resulting in an inability to reason with a moderate degree of sense and composure. … a child’s ability to reason with a moderate degree of sense and composure is reduced (compared to adults). Their moral responsibility is still developing. The phrase ‘moderate degree of sense and composure’ can be very difficult to interpret in many cases, even in cases of psychosis.156

The Commission’s conclusion

  1. 4.128 The Commission acknowledges the view expressed in submissions and consultations that in applying the defence of mental impairment to young people, the developmental stage of the young person must be taken into consideration.
  2. 4.129 Many of the views raised in relation to young people about a need for flexibility in applying the defence of mental impairment, were also raised in relation to applying the defence to adults.
  3. 4.130 The Commission’s recommendations regarding the defence of mental impairment for adults are intended to allow for the flexible application of the defence. A broad definition of mental impairment will take into account a range of conditions that may qualify for the defence, and clarification as to the meaning of the second limb of the defence will address the concern raised in relation to the application of the phrase ‘reason with a moderate degree of sense and composure’ to young people.

Recommendation

26 Recommendations 24 and 25 to introduce a definition of mental impairment and make changes to the second limb of the mental impairment defence in the higher courts should apply in the Children’s Court by adding equivalent provisions into the Children, Youth and Families Act 2005 (Vic).

 

Footnotes

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