Why is mental capacity so important to making a Will?

14 October 2016

Why is mental capacity so important to making a Will?

Disputes heard in the High Court over the validity of Wills have jumped from 97 cases in 2013, to 164 in 2015. Many of the judgements and decisions made were pivotal on whether or not a testator had the necessary mental capacity at the time their Will was written and signed.

Debilitating conditions such as Dementia are currently on the rise. At this moment there are over 850,000 people living in the United Kingdom right now with it and scarily, this figure is set to soar to 1 million people by 2025. This and unfortunately other illnesses and conditions can affect a person’s memory, their ability to understand and reason. These are all key attributes we look for when creating your Will.

When we at Redstone Wills create a Will for our clients we have to be very careful to ensure our clients have the necessary mental capacity to protect not only them, but also those benefiting from the Will. Fundamentally we are ensuring a client has sound mind, memory and understanding.

What determines mental capacity?

The test for mental capacity was laid down in the key case Banks v Goodfellow (1870) where it was shown:

    • The individual who is making the Will (the testator) must understand the nature of his act, that he is making a Will and its effects;


    • He must understand the extent of his property being disposed of, though need not remember every one of his assets; and


  • He must be able to comprehend and appreciate the concept of creating a Will; i.e. that he is setting out to who he wishes his property to pass to on his death.


If a Will appears to be rational then there is a presumption that the individual making the Will had capacity.

In Simon v Byford and Ors (2014) the individual could not remember why her existing Will did not benefit her children equally and was adamant to change it. Her previous Will dated 1996 was revoked and a new one written in 2005 at her 88th birthday party. The courts held that failure to not remember why she created her previous Will as she had done, did not mean she lacked capacity.

Interestingly, Lloyd v Jones and others (2016) found that mental delusions were only relevant to the creation of a Will if they affected the testamentary decisions made. In 2004 the individual was suffering from strange delusions, confusion and forgetfulness as a result of Alzheimer’s type dementia. It was found however that a Will created in 2005 was still valid no matter how bizarre any delusions the individual was suffering from at the time were. This is because the Will represented long standing intentions to distribute her assets and clear specific instructions were executed.

The ‘Golden Rule’

This being said, sometimes it may prove prudent to ensure that what is known as the ‘golden rule’ be applied. When an individual making a Will is elderly, or suffered/is suffering from an illness, the making of the Will ought to be approved or witnessed by a medical practitioner. Although this approval may not provide any guarantee against a Will being challenged successfully, it makes it a lot more difficult for those challenging it.

Likewise, other measures such as looking at the extent of any amendments being made and talking through our clients instructions with them, prior to any drafting, ensures that both them and those writing the Will can guarantee the Will is in accordance with their exact wishes.

In General, provided an individual had capacity when the Will was signed and witnessed, it may not matter later on if they later loses full capacity. Remember, the burden lays with the person challenging the Will to prove someone does not have capacity, and not the other way around.

The Mental Capacity Act 2005

Of course unfortunately, there may be times when a person is deemed to have lost capacity and not in the mindset to be able to amend or create a Will. The Mental Capacity Act 2005, which came into force on the 1st of October 2007, made radical changes regarding the treatment of persons who have been confirmed to have lost capacity.

Everyone working with and/or caring for an adult who may lack the capacity to make specific decisions, either life changing or everyday matters, must comply with the Mental Capacity Act. Under this act, the Court of Protection has the power to direct the execution of what is known as a statutory Will. This Will must be in the individuals best interest and the Court will look objectively at that persons past and present wishes and feelings. In particular, the Court will look at any past written statements made by them (i.e. past Wills) created when they did have capacity, and decide what weighting, if any, they should have on the creation of a new statutory Will.

Why us a specialised legal team?

The main thing to take from this is that the case law shows that an individual is potentially capable of having testamentary capacity one day but not the next. Factors relevant to the assessment of capacity include the complexity or an estate, the identity of the beneficiaries and the nature of assets. Every person is unique and every situation specific and different, therefore, it is practical not to make assumptions about a person’s mental capacity just because they are elderly or ill.

We recommend making your Will early on in life as regrettably the future is uncertain and anybody could end up in a situation where they lack mental capacity to create a Will or even die without a Will (intestate). Even simple spelling errors could invalidate your Will and confusing legal terminology could mean your estate is divided up differently, and perhaps incorrectly as to how you wish. Therefore, in an ever changing and somewhat contradictory area of law, it is easy to see as to why it is more important than ever to take specialised legal advice.

At Redstone Wills our dedicated legal team will be happy to assist you in the creation of your Will and ensure your assets are distributed exactly as you so wish. We will always take the necessary steps to confirm a client’s capacity to avoid there being potential future disputes over your estate. If you have any queries regarding what you have just read or wish to discuss anything further please call our Freephone number 0808 281 1545 or email This email address is being protected from spambots. You need JavaScript enabled to view it. and a member of our team will be delighted to assist you.


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