Can a Person With Dementia Make a Valid Will in Victoria?

Does Dementia Automatically Prevent Someone Making a Will?

No. A diagnosis of dementia does not automatically prevent a person from making a valid Will. Dementia is a medical term covering a range of conditions — Alzheimer's disease, vascular dementia, frontotemporal dementia and others — each of which progresses differently and affects different cognitive functions.

Importantly, capacity to make a Will is a legal question, not a medical one. A person can have a formal dementia diagnosis and still satisfy the legal test for testamentary capacity, particularly in the earlier stages of the condition. The converse is also true: a person without any formal diagnosis may, in particular circumstances, lack capacity.

The relevant question is not "do they have dementia?" but "did they have testamentary capacity at the time the Will was signed?" That distinction is fundamental and is the reason Wills and estate planning in Victoria is approached carefully rather than refused outright whenever a diagnosis exists.

What Is Testamentary Capacity?

Testamentary capacity is the legal test for whether a person is mentally capable of making a valid Will. The test in Australian law derives from the 1870 English case of Banks v Goodfellow, which continues to be applied in Victorian estate litigation today.

In plain English, a person has testamentary capacity if, at the time of signing the Will, they:

• Understand the nature and effect of a Will — that they are giving directions about who is to receive their property after they die;
• Understand, in general terms, what they own — the nature and extent of their property and assets;
• Understand who might reasonably expect to benefit — the people, such as a spouse, children or others, who might have a moral or legal claim on their estate; and
• Are free from any delusion or disorder of the mind that distorts their judgment or causes them to make decisions they would not otherwise make.

None of these limbs require perfect memory, perfect understanding of every asset, or detailed knowledge of tax law. The threshold is one of broad, functional understanding — not encyclopaedic recall.

How Is Capacity Assessed?

Capacity is assessed on a practical, functional basis. A careful solicitor preparing a Will for an older client, or for someone with a known cognitive condition, will typically explore the following areas in conversation:

• Understanding assets — can the person describe, in general terms, what they own? They do not need to know exact balances, but they should appreciate that they have (for example) a house, a superannuation account, some savings and perhaps a car.
• Understanding beneficiaries — can the person identify the people who might reasonably expect to benefit, and explain in their own words why they are including or excluding particular people?
• Understanding the effect of a Will — does the person appreciate that the Will operates on their death, that it can be changed during their lifetime, and that it will direct how their property is distributed?
• Rational decision-making — are the person's instructions internally consistent and stable over the meeting? Are they the product of considered thought, or are they driven by confusion, paranoia or the influence of others?

Where any of these areas appear uncertain, a prudent solicitor will not simply press on. They may ask further questions, see the client on a different day, see the client alone (without family members present), or seek a medical opinion before proceeding.

Can Capacity Fluctuate?

Yes. One of the most important features of dementia and many other cognitive conditions is that capacity can fluctuate — sometimes significantly — from day to day, and even within a single day.

A person with dementia may have "good days" when they are alert, oriented and able to give clear instructions, and "bad days" when they are confused, drowsy or unable to engage. Time of day can matter too. Many people with cognitive impairment are at their best in the morning, with capacity declining as the day progresses — a phenomenon often referred to as "sundowning".

Because capacity is assessed at the moment the Will is signed, timing matters. A Will signed during a lucid interval can be valid even though the Will-maker would not have had capacity on other occasions. Equally, a Will signed at a time of confusion may be invalid even if the person was capable on other days. This is why capacity assessments are highly fact-specific.

Why Medical Evidence Can Be Important

Where capacity may be in doubt, contemporaneous medical evidence can be invaluable. If a Will is later challenged — sometimes years after it was signed — the parties may need to reconstruct what the Will-maker understood at a particular moment in the past. Records prepared at the time are usually far more persuasive than opinions formed after death.

Helpful forms of evidence typically include:

• GP evidence — the treating general practitioner often knows the patient best over time and can comment on their general level of cognition during the period the Will was prepared.
• Specialist evidence — geriatricians, neurologists and psychiatrists are sometimes engaged to undertake a formal assessment of capacity, including standardised cognitive testing.
• Contemporaneous assessments — an assessment carried out close in time to the signing of the Will carries far more weight than a retrospective opinion attempted years later.
• Solicitor file notes — detailed file notes recording the instructions given, the questions asked, the answers received and the solicitor's observations of the client's presentation are routinely relied upon in capacity disputes.

None of these sources is conclusive on its own — a Court considers the evidence as a whole — but together they can create a powerful record of the Will-maker's capacity at the relevant time.

What Is the "Golden Rule"?

The "Golden Rule" is a long-standing practice direction in Australian and English Wills practice. It provides that, where a Will is being made by an older person or by someone whose capacity may be in doubt, the solicitor should arrange for a medical practitioner — ideally one familiar with the client — to assess and record the person's testamentary capacity at or about the time the Will is signed.

The Golden Rule is not a legal requirement. A Will can be valid even where no medical opinion was obtained. However, following the Golden Rule has two important benefits. First, it gives the Will-maker and their solicitor real-time confidence that the Will reflects considered wishes. Second, if the Will is later challenged, the medical assessment provides strong evidence of capacity at the critical moment.

For Victorian families dealing with a relative who has been diagnosed with dementia, the Golden Rule is one of the simplest and most effective protections against a future capacity dispute.

Can a Will Be Challenged for Lack of Testamentary Capacity?

Yes. A Will can be challenged in the Supreme Court of Victoria on the basis that the Will-maker lacked testamentary capacity at the time it was signed. Capacity challenges are a recognised ground for refusing a grant of probate or for setting aside a Will and reverting to an earlier Will or to the intestacy rules.

Capacity challenges are often heard alongside related grounds — most commonly allegations of undue influence, suspicious circumstances, fraud, or knowledge and approval issues. They are factually intensive proceedings, typically requiring detailed medical records, evidence from the solicitor who prepared the Will, and statements from family members, carers and others who saw the Will-maker around the relevant time.

Because capacity disputes can be complex, expensive and emotionally difficult, many are resolved through negotiation, mediation or a deed of family arrangement before reaching final hearing. Where the dispute affects the administration of the estate, it can also intersect with probate and estate administration and with deeds of family arrangement used to vary distributions by agreement.

Practical Steps for Families and Will-Makers

Where dementia or another cognitive condition is in the picture, the following practical steps will reduce the risk of a future dispute and help ensure that the Will-maker's wishes are properly recorded:

1. Act early — the best time to make or update a Will is before capacity becomes uncertain. If a diagnosis is recent, do not wait.
2. Use an experienced solicitor — choose a solicitor who routinely advises older clients and is familiar with the issues that arise around capacity, undue influence and family dynamics.
3. See the Will-maker alone — instructions should be taken privately, without family members or proposed beneficiaries in the room, so the solicitor can be confident the wishes are the Will-maker's own.
4. Consider a medical assessment — where there is any doubt, follow the Golden Rule and obtain a contemporaneous opinion from the GP or treating specialist.
5. Keep detailed records — instructions, questions, answers and observations should be carefully recorded in the solicitor's file at the time, not reconstructed later.
6. Review regularly — as circumstances and capacity change, it is sensible to review the Will rather than wait for a crisis.
7. Plan beyond the Will — make sure appropriate enduring powers of attorney and medical treatment decision maker appointments are in place while capacity remains.
8. Communicate where possible — open conversations with family members, while sensitive, can prevent surprises and reduce the chance of a contested estate later.

Conclusion

A dementia diagnosis does not, by itself, prevent a person from making a valid Will in Victoria. What matters is whether the person has testamentary capacity at the time the Will is signed — a legal test that looks at functional understanding rather than diagnosis.

Families, Will-makers and practitioners should approach the question carefully. With early planning, an experienced solicitor, careful file notes and — where appropriate — contemporaneous medical evidence, it is often possible for a person with dementia to make a Will that reflects their wishes and stands up to later scrutiny. Where capacity is genuinely in doubt and the person can no longer give valid instructions, other options (including an application to the Supreme Court for a statutory Will) may need to be considered.

If you are unsure whether a loved one has capacity to make a Will, or you are concerned about a Will that has already been signed, early legal advice is almost always the safest path.

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