Validity of wills and codicils - Effects of illness on capac...

Learning Outcomes

This article examines how illness affects testamentary capacity and the distinct requirement of knowledge and approval in the context of SQE1 FLK2, including:

• Interaction between illness and the Banks v Goodfellow test for testamentary capacity, the separate requirement of knowledge and approval, and how illness can generate a real doubt about either element
• Application of Banks v Goodfellow to dementia, delirium, psychiatric and mood disorders, bereavement, fluctuating medications, and hospital or hospice settings, with emphasis on fact-pattern analysis
• Lucid intervals, fluctuating conditions, and their role in supporting validity when capacity varies over time
• Distinction between the common law capacity test and the statutory approach in the Mental Capacity Act 2005, and how MCA principles inform good practice without replacing Banks v Goodfellow
• The Golden Rule, the importance of contemporaneous medical evidence, and what amounts to robust evidence of capacity in contested probate
• Timing of capacity (instructions versus execution), the presumption of capacity, shifting burdens of proof, and their deployment in examination problem questions
• Suspicious circumstances, illness-related red flags, and the need for heightened proof of both capacity and knowledge and approval
• Practical steps for assessing, recording, and evidencing capacity where illness may impair decision-making, and alternative routes such as statutory wills where capacity is absent

SQE1 Syllabus

For SQE1, you are required to understand how illness affects testamentary capacity and its interaction with knowledge and approval in will-making, with a focus on the following syllabus points:

• the Banks v Goodfellow test for testamentary capacity and its application in cases of illness
• the relevance and limits of the Mental Capacity Act 2005 in will-making
• the concept of lucid intervals and their effect on capacity
• the practical and ethical responsibilities of solicitors when illness may impair capacity (including the Golden Rule)
• how to advise on and evidence capacity in the context of fluctuating or deteriorating conditions
• timing of capacity: instructions versus execution, and the presumption of capacity and shifting burden of proof
• interaction between illness, capacity and knowledge and approval (including suspicious circumstances)

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. What are the three core elements of the Banks v Goodfellow test for testamentary capacity?
2. Does a diagnosis of dementia automatically mean a person cannot make a valid will?
3. What is a lucid interval, and how does it affect the validity of a will made during one?
4. What practical steps should a solicitor take if a client’s illness may affect their capacity to make a will?

Introduction

Testamentary capacity is a fundamental requirement for the validity of any will or codicil. Illness—whether physical, psychiatric, or cognitive—can affect a person’s ability to understand and approve the contents of a will. For SQE1, you must be able to apply the legal tests for capacity, understand how illness interacts with these tests, and know the practical steps solicitors should take to protect the validity of a will where illness is present. Importantly, capacity and knowledge-and-approval are separate requirements: a testator who has capacity must still know and approve the will’s contents, and illness can raise suspicion requiring stronger proof of this element.

Key Term: testamentary capacity
The legal ability to understand and make a valid will, assessed at the time the will is executed.

The Legal Test for Testamentary Capacity

The starting point for assessing capacity to make a will is the common law test from Banks v Goodfellow.

Key Term: Banks v Goodfellow test
The common law test for capacity to make a will, requiring understanding of the act, the property, and the possible beneficiaries.

The Banks v Goodfellow Test

The Banks v Goodfellow test requires that, at the time of making the will, the testator must:

1. Understand the nature of making a will and its effects.
2. Know the extent of the property being disposed of.
3. Comprehend and appreciate the claims to which they ought to give effect (i.e., who might expect to benefit).

A person may have testamentary capacity even if they are unwell, elderly, or have a diagnosed mental disorder, provided these elements are satisfied. In practice, “know the extent of the property” does not mean producing detailed valuations; a broad understanding of the estate suffices. The third limb requires the testator to be able to identify those with potential moral claims; it does not force the testator to benefit them.

Timing is critical. Capacity is assessed at execution, but if the testator had capacity when giving instructions, the will is prepared in accordance with those instructions, and at execution the testator understands they are signing the will reflecting those earlier instructions, capacity can be taken as present. This supports valid execution where cognition fluctuates.

Effects of Illness on Capacity

Illness can affect testamentary capacity in several ways. The law distinguishes between different types and stages of illness.

Cognitive Impairment and Dementia

A diagnosis of dementia or cognitive decline does not automatically remove capacity. The key question is whether the testator meets the Banks v Goodfellow test at the time of execution. Early-stage dementia may allow for valid will-making, especially for simple dispositions. As the illness progresses, capacity may be lost.

Cognitive conditions may fluctuate throughout the day (e.g., “sundowning” in dementia). A careful choice of time (often mornings), short meetings, and simple instructions can help assess and support capacity. Cognitive screening (e.g., MMSE or MOCA scores) may be informative but is not determinative: capacity under Banks v Goodfellow remains a legal test applied to the specific decision.

Key Term: lucid interval
A temporary period of mental clarity during which a person who otherwise lacks capacity regains sufficient understanding to make a valid will.

Psychiatric Illness and Fluctuating Conditions

Mental health conditions such as schizophrenia, bipolar disorder, depression or anxiety can cause capacity to fluctuate. A will made during a lucid interval—when the testator temporarily regains understanding—can be valid. Where delusions or disordered thinking exist, the question is whether they “poison the affections” or “pervert the sense of right” such that the will is influenced by the disorder. If the illness does not bear on the relevant decision, capacity can still be present.

Bereavement-related cognitive and emotional disturbance is common. Acute grief can resemble major depression and temporarily undermine decision-making. If evidence suggests decisions are made under the weight of acute bereavement without understanding the implications, capacity may be absent at that time. Waiting for stabilisation or arranging multiple assessments over time may be prudent.

Physical Illness and Medication

Physical illness, pain, infection (e.g., delirium secondary to UTI or pneumonia), or medication (such as strong opioids, benzodiazepines, sedatives, antipsychotics) can affect alertness, concentration and understanding. The test remains whether the testator can meet the Banks v Goodfellow criteria at the time of signing. In hospital or hospice settings, solicitors should plan around medication schedules, choose times of maximum lucidity, and liaise with clinical staff to understand the client’s likely cognitive state. Drowsiness, confusion or delirium can be transient; capacity might be present later the same day or on a different day.

Delusions

A person suffering from delusions may still have capacity if the delusions do not affect their understanding of the will or the claims of potential beneficiaries. Conversely, if fixed false beliefs directly drive the testamentary dispositions (e.g., a delusion that a child is an impostor or has stolen all property), the third limb of Banks v Goodfellow may not be satisfied. The key is whether the pathological belief influenced the will’s provisions.

The Mental Capacity Act 2005

The Mental Capacity Act 2005 (MCA 2005) sets out a statutory test for capacity for many decisions and imposes supportive principles (assume capacity unless proven otherwise; take all practicable steps to support decision-making; and recognise that an unwise decision is not evidence of incapacity). However, for wills, the common law Banks v Goodfellow test remains the standard. The MCA 2005 informs clinical assessments and good practice but does not replace the common law test for testamentary capacity. Case law has confirmed this approach, while recognising that MCA principles can assist the court’s evaluation.

Key Term: Mental Capacity Act 2005
Legislation providing a statutory test for capacity in England and Wales, but not replacing the common law test for wills.

Practical Safeguards: The Golden Rule

Where illness or age raises any doubt about capacity, solicitors must take extra precautions.

Key Term: Golden Rule
A best practice guideline requiring solicitors to obtain a contemporaneous medical opinion on capacity when a client is elderly or unwell.

Solicitors should:

• Arrange for a medical practitioner (ideally with relevant specialist knowledge in cognition or old-age psychiatry) to assess and confirm capacity close to the time of execution, with reasons addressing each Banks v Goodfellow limb.
• Ensure the testator understands the will and its effects, using clear explanations, avoiding legal jargon, and confirming comprehension in the testator’s own words.
• Keep detailed attendance notes of all meetings, dates/times, participants, client presentation, questions asked and answers given, and reasons for conclusions about capacity and knowledge and approval.
• Take instructions in private to reduce the risk of undue influence; consider multiple short meetings and staging instructions and execution to capture fluctuating capacity.
• If possible, have the medical practitioner present or act as a witness (with a second witness also present) and include a tailored attestation clause if the testator is blind or illiterate.
• Avoid complex dispositions where simplicity will suffice; complexity may demand higher cognitive load and complicate the capacity assessment.

Following the Golden Rule does not guarantee validity, but it provides strong evidence if the will is challenged. Failure to follow it is not fatal but may be scrutinised where illness or age was significant.

Worked Example 1.1

A solicitor is instructed by a client with early-stage Alzheimer’s disease to make a new will. The client can explain who their children are, what assets they own, and what the will does. The solicitor arranges for the client’s GP to assess capacity and witness the will.

Answer:
The will is likely to be valid. The client meets the Banks v Goodfellow test, and the solicitor has followed the Golden Rule to evidence capacity.

Worked Example 1.2

A client with schizophrenia has periods of confusion but is stable and lucid during a meeting with their solicitor. The client gives clear instructions and understands the will’s contents.

Answer:
If the will is executed during a lucid interval, and the client meets the Banks v Goodfellow test at that time, the will is valid.

Worked Example 1.3

A terminally ill patient on strong pain medication wishes to make a will. The solicitor finds the client drowsy and unable to explain the effect of the will.

Answer:
The client likely lacks testamentary capacity at that time. The solicitor should not proceed until the client is alert and able to meet the Banks v Goodfellow test.

Worked Example 1.4

An elderly client in hospital with a UTI-related delirium wants to change her will urgently. The delirium fluctuates; mornings are better. The solicitor attends twice, in the morning and late afternoon. In the morning, the client engages, explains her estate, and the intended changes; in the afternoon she is confused and tangential.

Answer:
Proceed, if possible, with execution during the morning period of lucidity, having a clinician assess capacity contemporaneously. A valid will can be made during a lucid interval; careful timing, medical evidence and detailed notes will support validity.

Worked Example 1.5

A bereaved widower seeks to disinherit his adult children the week after his wife’s death, asserting they abandoned him years ago. Records and recent communications show regular support from the children. He is tearful, indecisive and struggles to explain the effect of his proposed will.

Answer:
Acute bereavement may temporarily undermine decision-making. On the facts, capacity is doubtful. Advise delaying execution, reassessing later, and obtaining medical opinion. If he later consistently understands the act, the estate and potential claims, he may validly make the will—even if its terms are severe.

Worked Example 1.6

A client with a fixed delusion that her son is a non-relative insists on leaving everything to charity. She can otherwise explain her estate and the effect of a will.

Answer:
If the delusion directly drives disinheritance by preventing appreciation of the son’s legitimate claim, the third limb may not be satisfied and capacity could be lacking. If independent evidence shows the delusion and its causal impact on the disposition, the will may be vulnerable on capacity grounds.

Exam Warning

If a will is challenged on grounds of capacity, the burden of proof may shift. If the will appears rational and is properly executed, capacity is presumed. If evidence raises a real doubt, the person propounding the will must prove capacity. Illness, complex changes excluding expected beneficiaries, or recent bereavement may constitute “suspicious circumstances”, prompting the need for cogent proof of capacity and knowledge and approval.

Revision Tip

When illness may affect capacity, always advise contemporaneous medical evidence and keep detailed notes. This is essential for both validity and professional conduct. Where capacity is absent and unlikely to return, consider advising on an application to the Court of Protection for a statutory will.

Solicitor’s Duties and Ethical Considerations

Solicitors must balance respect for the client’s autonomy with the need to protect vulnerable clients from undue influence or exploitation. They should:

• Take instructions in private, away from potential beneficiaries, and record that this was done, noting who attempted to be present and why they were excluded.
• Be alert to signs of coercion or manipulation (e.g., third parties answering for the client, pressing for quick execution, arranging meetings around heavy sedation, or providing inconsistent narratives).
• Decline to act if not satisfied that the client has capacity or is acting freely; suggest reassessment, simplify dispositions, or delay if appropriate.
• Use plain language and ask the client to explain the plan back in their own words to confirm comprehension (both for capacity and for knowledge and approval).
• Consider the complexity of the proposed will relative to the client’s cognitive load; where illness impacts concentration and memory, simpler structures reduce risk.
• Document every step: dates, times, setting, persons present, questions asked, client’s verbatim explanations of key points, and rationale for concluding capacity and knowledge and approval.

If capacity is absent and not likely to return, a will or codicil cannot validly be made. In such cases, advise on the possibility of a statutory will via the Court of Protection (a distinct process governed by the MCA 2005), and manage expectations.

Key Point Checklist

This article has covered the following key knowledge points:

• The Banks v Goodfellow test is the legal standard for testamentary capacity.
• Illness does not automatically remove capacity; assessment is fact-specific and time-specific.
• Lucid intervals can allow a valid will even in fluctuating conditions.
• The Mental Capacity Act 2005 does not replace the common law test for wills; its principles may inform best practice.
• The Golden Rule is best practice when illness or age raises doubt about capacity, supporting robust evidence.
• Capacity and knowledge and approval are separate; illness may raise suspicious circumstances requiring stronger proof of both.
• Solicitors should obtain medical evidence, time meetings for lucidity, keep detailed records, and take instructions in private.
• Undue influence and lack of capacity are separate grounds for challenging a will; both must be considered when illness is present.
• If capacity is absent, a statutory will via the Court of Protection may be appropriate.

Key Terms and Concepts

• testamentary capacity
• Banks v Goodfellow test
• lucid interval
• Mental Capacity Act 2005
• Golden Rule