Assessing Mental Capacity - Guidance

One of the conditions which must be satisfied for a will to be valid is that the person making it must be of sound mind. With an ageing population, cases involving disputes over a testator’s mental capacity are becoming more common – it is estimated that up to two million people in the UK suffer from some form of dementia or brain injury.

Mental Capacity – Importance and Assessment

When a person lacks mental capacity, they are unable to create any valid legal agreement – for example to make a valid will. Challenges to wills on the ground that the testator lacked mental capacity are becoming increasingly common, especially when the will was made (or an existing will was changed) by someone of advanced years.

When it is feared that mental capacity may be lacking, it is possible for a test to be carried out to confirm the extent of a person's ability. The test involves two stages.

The first identifies whether there is an impairment of mental functioning which is sufficient to affect the ability of the person making the decision that is in point (e.g. making a valid will).

The second stage involves four further tests, which must all be satisfied to show that the person has mental capacity:

  • The person must be able to understand information relevant to the decision being taken;
  • The person must be able to retain that information for a period of time sufficient for them to make the decision;
  • The person must be able to evaluate the information relevant to the decision being made; and
  • The person must be able to communicate their decision.

If you are concerned that a family member may be losing mental capacity and there are 'loose ends' which should be tied up (such as creating a will or executing a power of attorney), it is important to make sure these matters are dealt with before mental capacity is lost.

Guidance on the meaning of mental capacity can be found on the Mental Health Foundation website.

The bar for a successful challenge to a will on the ground of a lack of mental capacity is set high. Cases from 2013 onwards make it clear that recurrent mental illness (schizophrenia) and being 'grief stricken' do not necessarily mean that a testator lacks the mental capacity to make a valid will.

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The contents of this article are intended for general information purposes only and shall not be deemed to be, or constitute legal advice. We cannot accept responsibility for any loss as a result of acts or omissions taken in respect of this article.