Friday 29th April 2022 from 9am

Wills & Estates Senior Associate Debbie Sage will join Robyn Hyland to talk about the importance of planning for end-of-life care and what options are available.

Challenging a Will based on mental capacity


Capacity can be an emotionally charged topic, especially in relation to Dementia or Alzheimer’s and other degenerative conditions. Estate Litigation Associate, April Kennedy, discusses how a Will might be challenged on the basis of mental capacity and why this is such an important issue.

What does capacity mean from a legal perspective?

There are different types and tests of capacity, including the capacity to:

  • make a Will
  • make a Power of Attorney (POA)
  • enter into legal proceedings
  • enter into a marriage

When discussing Wills, we are referring to ‘testamentary capacity’. There’s an old English case which is still good law today called ‘Banks v Goodfellow’ and this sets out what the test for testamentary capacity is. When making a Will, a person must:

  1. understand the nature and effect of a Will – a person must understand the legal document they are preparing, and that it forms their wishes after they pass away.
  2. understand the nature and extent of their property – a person must have a good idea as to what they own, whether that be property, shares, bank accounts. For example, those who own a bank account must know which financial institution they bank with, and the approximate value of those bank accounts.
  3. comprehend and appreciate the claims to which they ought to give effect – a person must be able to understand they have a moral obligation to provide for, and the effect of the gifts they are giving, in their Will. They must be able to appreciate that they have a moral obligation to provide for a dependent person, whether that be a spouse or a child, and they must understand how much they ought to provide them and whether that provision is considered ‘adequate’ for their proper maintenance, support and advancement in life.
  4. not be suffering from any disorder of the mind or insane delusion that would result in an unwanted disposition – this is old terminology but a person must not be suffering from any condition that affects their mind and capacity to make decisions whilst taking into consideration the above factors. This arm of the test refers to conditions such as dementia, Alzheimer’s Disease, etc.

Sometimes it is a difficult exercise to determine whether someone has the requisite testamentary capacity to provide instructions for a Will when they are suffering from dementia or some other injury caused condition or illness (e.g. a head injury or stroke). In the 19th century English House of Lords case of Boyse v Rossborough (1857) 6 HL Cas 1 at 45, Lord Cranworth, who was also the Lord Chancellor, observed the difficulty in relation to this test:

“There is no possibility of mistaking midnight for noon; but at what precise moment twilight becomes darkness is hard to determine.”

This case and this comment were referred to and accepted by the same Court in Banks v Goodfellow, some 13 years later and continue to be applied to this day by our state Supreme Courts and the High Court of Australia.

On what grounds can a Will be challenged based on capacity?

There are many ways a person can challenge a Will based on the capacity of the Will-maker (or lack thereof). It is a heated area of law. Sometimes when a person is unhappy with the contents of a person’s Will and the Will-maker exhibits subtle symptoms that resemble dementia, such as forgetfulness, then they will use that as grounds to challenge the Will. It can be difficult to determine whether there are grounds to challenge a Will on this basis, so it is important to seek advice early on.

The most common types of claims when someone is challenging a Will based on capacity, include conditions such as:

  • Dementia
  • Alzheimer’s
  • Degenerative conditions or diseases, such as Parkinson’s or Motor Neuron Disease
  • Conditions that can affect your speech and physical capabilities are generally considered when determining capacity in these types of claims.

People may not necessarily lack capacity, but they might display paranoid behaviour where they change their Will after believing things that may not necessarily be true. They may have a certain perspective that is skewed which can impact their decision making.

Are there other ways a Will can be challenged based on someone’s mental state?

Yes. There are grounds to challenge a Will based on emotional or psychological pressure put upon the person writing the Will. For instance, the will-maker might be under duress or being unduly influenced by a third party.

The most common instance of this behaviour is when a family member or carer becomes part of the Will-maker’s life in a big way. That person accompanies the Will-maker to their solicitor to have their Will made during those later stages in their life. This can create a pressure environment where the Will-maker feels obligated to change their Will to include this person and cut out other family members who they may have been close to their entire life. The Will-maker may feel obliged to do this as a way of repaying someone for their companionship or friendship.

This is not a medical disorder, but it is a sense of obligation or pressure that otherwise influences the Will-maker. This is prevalent in the elderly and considered elder abuse.  Especially because elder people can be vulnerable and susceptible to psychological or emotional pressure. For this reason, it is necessary to determine whether the Will was prepared under ‘suspicious circumstances’.

Another challenge may be based on lack of knowledge and approval of the Will. These types of claims usually arise when there’s a DIY Will, or a handmade Will, especially if the person making the Will is either:

  • deaf
  • unable to speak
  • paralyzed or unable to write
  • blind; or
  • illiterate

In these cases, they may have had someone else sign the Will on their behalf because they were physically unable to do so themselves. A knowledge or approval claim is essentially someone contesting the Will on the basis that that person did not know what they were signing.

What evidence might be used in a Will contest on the grounds that the Will-maker had impaired capacity?

For these types of claims, the main types of evidence used are:

  • Medical reports and clinical notes
  • Specialist reports
  • Witness statements from people who knew the deceased and knew the history of the relationship between the parties involved
  • Telephone log history and bills
  • Bank account statements
  • Facebook messages
  • Social media posts and history
  • Handwritten notes
  • Photographs to show history of relationships between parties
  • Digital notes in a person’s mobile or tablet device

It can be very costly to challenge a Will on capacity and evidence is critical to determining if a claim has merit.

What can people do to ensure there are no questions over the Will-maker’s capacity?

It is recommended to have a Will prepared by a solicitor, especially if there are going to be capacity issues or if there are any suspicions someone may make that claim down the track.  Memory loss, early stages of dementia or any physical impairment that may leave a Will-maker open to someone making a capacity claim should be handled with care by an experienced solicitor who can mitigate these risks.

We’ve seen these reasons, and many more, result in Will contests.

Should someone obtain medical reports at the time of making a Will?

Yes – that is the first step we take in these situations, especially if we suspect a capacity issue could arise. Capacity can be a sensitive topic to talk about, especially with the elderly. It is a hard topic to broach and it can be difficult to say to someone that we consider you may not have capacity, or we want to ensure that you do have capacity in order to write a Will. These questions can be demeaning to someone, however at Attwood Marshall Lawyers, we’re trained to handle capacity issues in a professional way. It might not necessarily be the Will-maker’s capacity we are concerned about, it may be regarding a family member or third party who accompanies that person to their appointment and we can see they are making a dramatic change to their Will. In these instances, having a letter from their doctor will serve them down the track.

Another step we take is performing our own test during the course of the interview with a client. We have contemporaneous file notes. This is crucial to these types of claims.

There are several cases that suggest the evidence provided by the solicitor who prepared the Will were preferred to medical reports. The reason for this is that testamentary capacity is a legal test, not a medical test. Unfortunately, when it comes to do-it-yourself Wills, there’s no evidence of this kind if someone was to contest on these grounds. Therefore, those types of documents will often be contested.

What if someone has been diagnosed with early stage dementia?

A diagnosis like this doesn’t necessarily mean you can’t make a Will. There are different stages of dementia, or degenerative conditions, and it doesn’t automatically mean you do not have capacity. There are certain stages even in later stage dementia where a person can have lucid periods. An experienced estate lawyer will be able to help you navigate these issues and concerns, can help you make a Will, making sure appropriate notes are taken and all the evidence is documented.

How can Attwood Marshall Lawyers help?

It is important to seek immediate advice if you have concerns about the validity of a person’s Will. After that person passes away, there is usually a brief window of opportunity to take steps to ensure that the Will was properly made. Challenging the validity of a Will can be daunting, so it is important to seek advice from a lawyer who is knowledgeable and has experience in this complicated area of law.

At Attwood Marshall Lawyers we have one of the largest Wills & Estates departments in South East Queensland, which contains experienced lawyers, graduates and paralegals who practice exclusively in this area. We spend time to educate our lawyers about effectively communicating and connecting with our clients. This ensures we can offer clients the best advice and assistance when coming to terms with the provisions of their Will and estate litigation matters.

If you think you are eligible to contest an estate and would like further advice please contact Estate Litigation Department Manager, Amanda Heather, on direct line 07 5506 8245, email or phone 1800 621 071.

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april kennedy estate litigation lawyer

April Kennedy

Special Counsel
Estate Litigation

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The contents of this article are considered accurate as at the date of publication. The information contained in this article does not constitute legal advice and is of a general nature only. Readers should seek legal advice about their specific circumstances. 

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