Introduction
The decision in CK [2025] WASAT 27 provides significant guidance on the requirements for valid Advance Health Directives (AHDs) in Western Australia, particularly regarding the capacity necessary to execute such instruments.
The case is notable for its detailed examination of the 'full legal capacity' test under the Guardianship and Administration Act 1990 (WA) ('GA Act') and its application to persons with cognitive impairments.
This decision clarifies the standards that must be met for an AHD to be legally enforceable, especially concerning consent to medical research—an area that has seen legislative development in recent years following the COVID-19 pandemic.
The case has substantial implications for legal practitioners advising clients on AHDs, medical practitioners assessing capacity, and substitute decision-makers navigating complex healthcare decisions. It also addresses the critical intersection between autonomy in healthcare decision-making and protection of vulnerable individuals.
Detailed Facts of the Case
Background and Initial Orders
CK, a 63-year-old man, was diagnosed with Autism Spectrum Disorder (ASD) at age 61 after being found dehydrated and wandering the streets following his mother's sudden death in late 2022 (at [1]). The Tribunal initially appointed the Office of the Public Advocate as CK's guardian in early 2023 to make decisions about services (the '2023 Orders') (at [1]).
Execution of Legal Documents
In late 2023, CK signed several legal documents, including:
A will
An enduring power of attorney appointing his younger sister EK as attorney
An advance health directive recording consent to participate in medical research ('CK AHD') (at [2])
Deterioration and Further Applications
In August 2024, CK was admitted to hospital following a significant decline in his mental health. He had stopped taking medication after hearing voices that instructed him to do so. He was subsequently diagnosed with schizophrenia (at [3]). During this admission, concerns arose about financial transactions, with allegations that CK had given significant sums to EK to pay her mortgage and purchase diamonds (at [3]). This prompted the Hospital to seek review of the 2023 Orders and appointment of an administrator (at [3]). The Tribunal appointed the Public Trustee as emergency administrator (at [3]).
The Advance Health Directive Issue
At the October 2024 hearing, CK expressed that he did not want to participate in medical research where he would receive a placebo, yet this was precisely what he had agreed to in the CK AHD (at [4]). The Tribunal accepted an oral application from CK to determine the validity of the CK AHD (at [4]).
Final Orders
At the November 2024 hearing, the Tribunal appointed the Public Trustee as CK's administrator and reappointed the Public Advocate as his guardian. Critically, the Tribunal revoked the enduring power of attorney and declared the CK AHD invalid (at [5]).
Analysis of the Tribunal's Reasoning
Legal Framework for Advance Health Directives
The Tribunal's analysis begins with the fundamental legal requirements for creating a valid AHD under Part 9B of the GA Act. Section 110P provides that a person who has reached 18 years of age and who has "full legal capacity" may make an AHD containing treatment decisions for future treatment (at [16]).
Notably, the GA Act does not define 'full legal capacity'. The Tribunal referred to the Western Australian Department of Health's guidance, which describes this standard as requiring that a person:
Understands information or advice relevant to decisions in the AHD
Understands the likely effects of decisions on future treatment
Can weigh potential pros and cons of decisions
Can communicate decisions about future treatment (at [16])
Medical Research Consent Provisions
The Tribunal considered the 2020 amendments to the GA Act introducing Part 9E, which created mechanisms for substitute decision-makers to consent to medical research for people lacking capacity (at [17]). The Tribunal noted that in August 2022, the prescribed AHD form was expanded to include a section allowing consent to participate in medical research (at [18]).
Assessment of CK's Capacity
The Tribunal employed a multi-faceted approach to determine whether CK lacked capacity at the time of executing the AHD:
Evidence of Mental Disability: The Tribunal found that CK's diagnoses of ASD, schizophrenia, and cognitive impairment constituted a 'mental disability' within the meaning of the GA Act (at [31]).
Capacity for Financial Decisions: Extensive evidence demonstrated CK could not manage day-to-day finances without assistance, including inability to calculate necessary expenditure, identify financial implications of decisions, or implement problem-solving strategies for financial issues (at [47]).
Capacity for Personal Decisions: Medical evidence indicated CK lacked capacity to make medical treatment decisions due to impaired understanding of illness and treatment requirements (at [55]). He also showed limited ability to make accommodation decisions or identify service needs (at [56-57]).
Understanding of the AHD Terms: The Tribunal found a crucial disconnect between CK's expressed wishes and the content of the AHD. While CK clearly articulated not wanting to receive a placebo in research, the AHD he signed explicitly consented to this (at [24]). This demonstrated he did not understand the nature or consequences of the treatment decisions in the document when he signed it.
The Tribunal concluded that CK lacked the "full legal capacity" required under s 110P of the GA Act at the time the AHD was executed (at [58]). This finding formed the basis for declaring the AHD invalid under s 110W (at [82]).
Practical Application: A Doctor's Guide to Capacity Assessment for AHDs
When assessing capacity for an AHD, medical practitioners should follow this structured approach based on the CK decision:
Step 1: Assess Understanding of General Information
Does the person understand what an AHD is?
Can they explain the purpose of the document in their own words?
Do they understand when the AHD would take effect? (i.e., when they can no longer make decisions)
Step 2: Evaluate Comprehension of Specific Treatment Decisions
Ask the person to explain each treatment decision included in the AHD
For medical research consent, determine if they understand:
The difference between treatment and research
The concept of placebos and control groups
That research may not improve their condition
The specific types of research they are consenting to
Step 3: Test Ability to Weigh Consequences
Ask the person to explain potential benefits and risks of each decision
Determine if they can articulate why they are making specific choices
Assess if they can explain how the decisions align with their values and preferences
Step 4: Identify Red Flags from the CK Case
Discrepancy between verbal statements and written consent (as with CK's placebo consent)
Evidence of influence from family members or others
Demonstrated deficits in managing other aspects of life (financial matters, healthcare)
Recent significant medical or psychiatric diagnoses
Evidence of cognitive fluctuations or decline
Step 5: Document the Assessment Process
Record specific questions asked and responses received
Document the person's explanation of treatment decisions in their own words
Note any concerns about capacity and how these were explored
Consider obtaining a specialist psychiatric or geriatric assessment if concerns arise
Step 6: Reassess When Necessary
If the person's condition fluctuates, consider reassessment when they are at their best
For progressive conditions, earlier documentation is advisable
Guidance for Legal Practitioners
Initial Client Assessment
Preliminary Capacity Screening
Observe client's ability to maintain focus during consultation
Ask open-ended questions about the purpose of the AHD
Assess consistency of instructions across multiple meetings
Document observations contemporaneously
Client Interview Strategy
Meet with the client alone initially
Use clear, simple language avoiding legal jargon
Break down complex concepts into manageable parts
Allow sufficient time for questions and clarification
Red Flags Requiring Further Investigation
Recent significant diagnoses (as with CK's late-life ASD diagnosis)
Family members providing instructions or answering for the client
Pronounced memory difficulties or confusion
Inconsistent instructions or significant changes to previous arrangements
Documentation and Professional Collaboration
Medical Evidence
Obtain specific medical opinion on capacity for AHD purposes
Ensure medical report addresses the elements of full legal capacity
Consider specialist assessment for clients with cognitive impairments
Document attempts to obtain medical evidence
Drafting Considerations
Use clear, simple language in the AHD
Include explanatory notes for complex decisions (particularly research consent)
Document discussions about the consequences of specific decisions
Consider video recording the execution and explanation process
Execution Process
Allow sufficient time for final review and questions
Ask the client to explain key decisions in their own words
Document the client's explanations
Consider involving an independent witness beyond statutory requirements
Post-Execution Practice
Regular Reviews
Recommend periodic review of the AHD, especially after significant health changes
Document client's continued understanding at each review
Update the AHD when necessary to reflect changed circumstances or wishes
Record Keeping
Maintain detailed file notes of capacity assessment process
Preserve all drafts and records of client instructions
Document reasons for proceeding despite any concerns
Evidence and Arguments
Evidence Supporting AHD Validity
Medical Evidence
Reports showing stable cognitive function at time of execution
Specialist assessments confirming decision-making capacity
Documentation of client explaining treatment decisions consistently
Procedural Evidence
Contemporaneous file notes showing thorough explanation process
Evidence that medical terminology was explained in plain language
Documentation showing client initiated the AHD process independently
Witnesses attesting to apparent understanding
Arguments for Validity
Diagnosis alone (e.g., ASD as in CK's case) does not automatically negate capacity
A person may have capacity for some decisions but not others
The right to make unwise decisions is preserved if understanding is present
Fluctuating capacity may include periods of valid decision-making
Evidence Supporting AHD Invalidity
Medical Evidence
Diagnoses affecting cognition or decision-making (as with CK's schizophrenia)
Clinical observations of confusion or limited understanding
Documentation of inability to manage other aspects of life (as with CK's finances)
Contradictory Statements
Documented statements contradicting the AHD terms (as with CK's placebo objection)
Inconsistent explanations of treatment decisions
Inability to explain consequences of decisions when questioned
Arguments for Invalidity
Failure to meet any element of the "full legal capacity" test is sufficient
The complexity of medical research consent requires sophisticated understanding
Evidence of influence or pressure from family members
Protection of vulnerable persons is a primary consideration
Key Takeaways for Legal Practice
Capacity Assessment is Multi-Dimensional
Capacity must be assessed specifically for the decision at hand
Evidence from multiple domains (financial, personal, healthcare) may be relevant
Medical diagnosis alone is insufficient—functional assessment is crucial
Medical Research Consent Requires Special Attention
The CK decision highlights particular vulnerability in research consent
Specific explanation of concepts like placebos and experimental treatments is essential
Practitioners should consider additional safeguards for research consent provisions
Documentation is Critical
Thorough contemporaneous records of the capacity assessment process
Documentation of explanations provided and client's demonstrated understanding
Evidence of steps taken to enhance understanding (plain language, visual aids)
Collaborative Approach
Engage with medical practitioners early in the process
Consider involving allied health professionals (psychologists, occupational therapists)
Multi-disciplinary assessment may strengthen the validity of the AHD
Risk Management
Identify high-risk clients who may require additional safeguards
Consider declining to act if capacity concerns cannot be resolved
Be prepared to justify the basis for proceeding despite potential concerns
Conclusion
The CK decision provides valuable guidance on the standards for valid AHDs in Western Australia, particularly regarding the capacity required for medical research consent. The case emphasises the importance of a person's functional understanding of treatment decisions rather than merely focusing on diagnostic criteria.
For legal practitioners, the decision underscores the need for thorough capacity assessment processes, meticulous documentation, and careful explanation of complex medical concepts. It highlights the tension between respecting autonomy in healthcare decision-making and protecting vulnerable individuals from consenting to procedures they do not fully comprehend.
The broader significance of this case extends beyond AHDs to inform practice in other areas requiring capacity assessment, including enduring powers of attorney and wills. As medical research continues to advance and legal instruments become increasingly complex, practitioners must develop robust methods for ensuring clients genuinely understand the documents they are executing.
The CK decision serves as a reminder that valid execution of legal documents requires more than mere formal compliance with signing requirements—it demands genuine understanding of content and consequences, particularly for vulnerable clients with cognitive impairments.