Mental Capacity

For a Will to be valid, the person who made the Will must have had testamentary capacity at the time they signed it. If they did not have testamentary capacity, the Will is not valid, and the person’s estate will be distributed in accordance with their last valid Will. If there is not an earlier valid Will, their estate will be distributed in accordance with the Intestacy Rules. This is one of the most common reasons that we are instructed by clients to challenge a Will.

What is ‘testamentary capacity’?

There is a legal test which is applied to determine whether a person had testamentary capacity. It comes from the case of Banks v Goodfellow [1870] LR 5 QB 549 and says that the following are required for a person to have testamentary capacity:

1. The testator must have understood the nature and the effect of making their Will;
2. They must have understood the extent and value of the assets they are giving away in their Will;
3. They must have understood and considered any claims against the Will which could be brought by anyone who might be disappointed by the Will;
4. They must not have been suffering from any ‘disorder of the mind’ which caused them to make a gift which they would not have made had they been of sound mind.

If the person passed this test at the time their Will was written, they are said to have testamentary capacity, and their Will is valid.

How is testamentary capacity proved?

It is the responsibility of the executor to prove that the Will is valid, which includes showing that the testator had capacity. Usually, as long as the Will looks rational, it will be presumed that the testator had capacity, so the executor does not need to do anything more to prove this.

Where there is doubt over the testator’s capacity a person may want to bring a challenge to the Will. When doubt exists, the executor would then have to prove that the Banks v Goodfellow test was passed. The types of things which might cast doubt over whether the testator had capacity include:

• Close relatives being excluded from the Will;
• Gifts, particularly large gifts, to people or organisations which the testator had little or no connection to;
• The testator being elderly when they made the Will;
• The testator suffering from a cognitive health condition such as dementia or Alzheimer’s when they made the Will;

The person challenging the Will should get hold of the file of the firm who wrote the Will, the testator’s medical records, and possibly an expert medical report, as these will all help to create a better picture of the testator’s capacity at the time the Will was made. The executor, who should remain neutral in a challenge to the Will, should authorise the release of these documents to the person challenging the Will if they are asked to do so.

What about the Mental Capacity Act?

The Mental Capacity Act 2005 sets out a list of factors which are relevant to determining whether a person has capacity to make a decision, but it does not apply to testamentary capacity and does not replace the Banks v Goodfellow test. However, if medical records show that a testator had failed a test for capacity under the Mental Capacity Act around the same time they made their Will, this could be useful evidence in support of a challenge to the Will.

My relative had dementia when their Will was made. Is their Will invalid?

This is a common question, and the answer is ‘not necessarily’. A condition such as dementia is often relied upon as evidence supporting a challenge to a Will on the grounds of a lack of testamentary capacity and is likely to influence a Court, but a diagnosis of a cognitive condition on its own is not enough to succeed on a claim. This is because the person’s condition might not have been affecting their testamentary capacity at the time they made the Will. Medical professionals refer to these as ‘lucid intervals’, and a Will made by a person with a cognitive condition during a lucid interval may well be valid.

Proving that someone lacked capacity to make a Will is a complex and often difficult process, so it is essential to take legal advice at an early stage.

If you have any concerns, please contact a member of our probate disputes team in confidence here or on 02920 829 100 for a free initial call to see how they can help.

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