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Challenging a will because of mental incapacity

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It is possible to challenge a will on the basis that the deceased lacked testamentary capacity. If you have concerns that the deceased’s wishes were not accurately reflected in their will because their decision making was adversely affected by mental illness, mental incapacity, delusion or dementia, you should seek legal advice. It may be possible to challenge a will if you have been excluded from the will or the will is unfair. These cases are difficult to prove and it is best to seek the advice of an expert will dispute solicitor.

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Testamentary Capacity

In order to be able to make a will, the testator (the person making the will) must be shown to have both testamentary capacity and testamentary intention. They should understand the nature of a will and its effect; they should have a reasonable understanding of their property; be able to understand who may have a claim on their estate.

Minimum Age for making a Will

In Australia, all States and Territories have enacted legislation which specifies the minimum age for making a valid will as 18 years. However, in some jurisdictions eg NSW and Victoria, a married person can make a will even if they are under 18 years of age. There are also provisions in some states for a minor to make a will if leave of the court is granted to make a will.

You may ask why a child or minor would want a will? It may be the case that the child may have acquired a large inheritance or a compensation award but the rules of intestacy would allow inappropriate distribution of their estate. For example, a child being cared for by grandparents and having no contact with the parents, if there was no will, the parents would benefit from the intestacy rules. If there is a will, the child’s assets can be passed into the grandparents.

Assessing Mental Capacity

The test is that the testator must have “sound mind, memory and understanding,” Banks v Goodfellow (1870) LR 5 QB 549. It basically means that the testator has to have the capacity to remember, reflect and reason. The test is a legal one. It should be noted that just because a person may be diagnosed with a mental illness or is subject to a guardianship order, or suffers from alcoholism does not automatically create a presumption that a person lacks testamentary capacity. Though, evidence can be put to a court that a mental illness or a delusion has affected the testator’s decision making when they created their will.

A person does not have to understand every single clause in a will. It is enough if they understand they are making a will and they have a general knowledge of the property they are disposing of, and they generally understand that certain persons may have a moral claim on the testator.

Can I make a will if I have dementia?

Dementia alone does not imply loss of testamentary capacity. Much will depend on the type of dementia and the degree of its effect on the person. If a solicitor has real concerns as to a person’s testamentary capacity being affected by dementia, they should speak with the client’s doctor and if appropriate, obtain a written opinion. They could also consider taping the interview.

In relation to dementia, there is the Victorian case of Kantor v Vosahlo [2004] VSCA 235, where the testator had dementia though evidence was provided by the solicitor who drew up the will (and was also a long-term friend) that the will was made in a lucid interval. During this lucid interval, the testator was able to give sound reasons as to why they were choosing the new beneficiaries and they could tell the solicitor the extent of the property they possessed. The court accepted this evidence.

Onus of Proof and Evidence of Mental Capacity

A presumption of capacity is usually raised if the will is rational in its face and properly executed. Evidence may be provided by someone challenging the will that the testator lacked capacity. The burden then shifts back on to the propounder of the will to show capacity. The standard of proof required is the balance of probabilities.




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