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Testamentary Capacity (WA)


It is a precept of succession law that only those with testamentary capacity can make a will. This means that a testator must be competent enough to understand their actions in making a will, be able to recall in broad terms the assets within their estate, and understand that there are people who are entitled to inherit from their deceased estate. When someone has concerns about a testator’s testamentary capacity, they can petition the Supreme Court to challenge the will. This article defines testamentary capacity rules in Western Australia and explains how the Supreme Court of Western Australia assesses challenges to a will based on lack of capacity.

What is Testamentary Capacity?

From the Latin testamentarius, testamentary means “pertaining to a will”. To have testamentary capacity is to have sufficient competence to create or amend a will. In Western Australia, a testator is presumed to have adequate capacity unless compelling evidence is presented to the contrary.

The only people who are able to challenge the validity of a will on the basis of testamentary capacity are the deceased’s family, a dependent of the testator, or a beneficiary of a previous will. The Supreme Court of Western Australia will assess a challenge to a testator’s capacity using a judicial test from an 1870 case: Banks v Goodfellow. This British case was a landmark decision because it created precedent that a testator suffering from a mental condition or disorder can legally make a valid will, as long as they:

  1. Comprehend the effect of writing a will;
  2. Remember (at least in general terms) what assets are included in the estate;
  3. Understand that certain people are entitled to inherit from the estate; and
  4. Do not suffer from a disorder that prevents them from making rational decisions about their will.

As this early case demonstrates, the case for testamentary incapacity must be compelling in order to invalidate a will. While a family member may worry that they observed signs of mental frailty in their relative before their death, this may well not rise to the level of testamentary incapacity. The court will assess a challenge based on the circumstances of the particular case, with emphasis on the type of disorder and severity of the testator’s illness, and how this might impact on the testator’s capacity to make rational choices.

Challenging a will on the basis of lack of testamentary capacity

Someone who intends to challenge a will on the basis of insufficient testamentary capacity should first file a probate caveat with the Supreme Court of Western Australia. This is only possible in the period before the court grants the executor a grant of probate to administer the will. Once a caveat is issued, the next step for a caveator is to make an official challenge of the will to the court.

At the court hearing to examine the validity of the will, both the executor and the caveator will have a chance to present evidence to support their respective cases. On the basis of this evidence, the court will either reject the challenge and probate the will, or find cause to invalidate the will and move to probate a previous will. In the event that there is no earlier will, the court will order that the deceased estate be administrated according to the intestacy provisions of the Administration Act 1903.

Establishing Testamentary Capacity

Testators who are elderly or suffer from cognitive or psychological impairment are particularly at risk of having their will challenged. Testators often express concern when drawing up their will that their wishes might be questioned on the basis of testamentary incapacity. There are ways for a testator in such circumstances to take actions to forestall a future challenge to the validity of their will. Firstly, it is crucial that a testator engage an experienced solicitor to draw up their will, instead of making an informal will or relying on a will kit. It is established practice that a solicitor will not accept instruction from a client unless they are convinced that a testator has capacity to make rational decisions about their deceased estate. In this way, the court may be more inclined to assume that a testator had testamentary capacity if an experienced solicitor prepared the will.

Furthermore, if it is likely that someone will challenge the testator’s capacity because of age, disease or disability, then it is highly recommended that the testator obtain a physician report on their cognitive status at the same time that they execute the will. The physician’s report can be kept with the will and provided to any parties who have doubts about the deceased’s testamentary capacity. The report will be a key piece of evidence in the event that there is an official enquiry into the validity of the will.

Case Study

In the case of Gangemi v Monaco [2020], the Supreme Court of Western Australia considered whether the deceased, Anna Marie Zanni, had testamentary capacity when she wrote a new will at the age of 85. The deceased was diagnosed with progressively worsening Alzheimer’s type dementia after making her first will in 2006 and before making her subsequent will in 2013. In 2019, an executor of the 2013 will applied for and was granted probate for this later will. The plaintiff then commenced proceedings to revoke the grant of probate and validate the earlier will, asking for a court declaration that the deceased did not have testamentary capacity when she made the 2013 will.

The court noted in summary that the Banks v Goodfellow approach does not require perfect memory and mental acuity. A testator has testamentary capacity provided that they have sufficient intelligence to appreciate and understand the testamentary act.

The court observed that a respected law firm prepared the 2013 will and that it was executed properly and was rational on its face. The onus was clearly on the plaintiff to prove that the deceased did not have testamentary capacity.

The court remarked on the fact that the same executor had been before the court to validate the will of the deceased’s husband, and produced detailed factual evidence of the steps taken to establish the husband’s capacity to make a will, but there was a “puzzling” lack of similar evidence presented in the current case.

The plaintiff presented affidavits from a list of people, including a specialist in geriatric medicine. The specialist noted that while he was never called upon to perform a “will assessment”, during his examinations of the deceased he had ascertained that she “did not have financial capacity”, and that making anything other than a trivial financial decision would be beyond her ability at that time. The specialist emphasised her consistently poor memory, lost financial capacity, and found that the fact that she required assistance for daily living was indicative of highly advanced dementia. Another affidavit prepared by the deceased’s general physician stated that the deceased could not make reasonable decisions about her own health, living situation or financial affairs. He concluded that she did not have the capacity to make out a power of attorney. This medical evidence was supported by several lay opinions from those people who were familiar with the deceased’s deteriorating mental capacity. The court found this combination of evidence to raise significant doubt as to the deceased’s capacity.

The court was satisfied on the basis of submitted evidence that the deceased did not have testamentary capacity when she executed the 2013 will, as she did not understand the extent of her property and was unlikely to have the cognitive capacity to form proper appreciation of the terms of the will. Accordingly, the court revoked the grant of probate on the 2013 will. The court also found that the term of the 2006 will were rational and executed properly, and should be probated.

The contested wills team at Armstrong Legal has a wealth of experience in all aspects of wills and estates, and are particularly qualified to help if you have doubt about a loved one’s will or if you wish to safeguard against challenges to your own will on the basis of testamentary incapacity. Please call 1300 038 223 or get in touch with our friendly team to discuss your legal needs today.

Dr Nicola Bowes

This article was written by Dr Nicola Bowes

Dr Nicola Bowes holds a Bachelor of Arts with first class honours from the University of Tasmania, a Bachelor of Laws with first class honours from the Queensland University of Technology, and a PhD from The University of Queensland. After a decade working in higher education, Nicola joined Armstrong Legal in 2020.

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