Establishing testamentary capacity
Testamentary capacity is the legal term used to describe a person's legal and mental capability to make a valid Will.
If a testator (i.e. the person making the Will) lacks testamentary capacity at the time the Will is executed (or at the time the testator gave instructions to the will drafter for the preparation of the Will), then the Will is invalid. It is therefore vital to ensure that all testators have the necessary capacity to make a Will.
The test used to determine whether a testator has capacity to execute a valid Will was established in the historic case of Banks v Goodfellow  which provides that a testator must:
- Understand the nature of making a Will and its effects;
- Understand the extent of the property of which he/she is disposing;
- Be able to comprehend and appreciate the claims to which he ought to give effect;
- Have no disorder of the mind that perverts his sense of right or prevents the exercise of his nature faculties in disposing of his property by Will.
After the introduction of the Mental Capacity Act 2005 there was initially some doubt as to whether the common-law test provided for in Banks v Goodfellow was superseded by the statutory test set out in the 2005 Act. However it was confirmed in the recent case of Walker v Badmin  that "the correct and only test" for testamentary capacity is the one outlined in Banks v Goodfellow.
Mental illness and testamentary capacity
It is often thought that simply because a person suffers with a mental illness they do not have the necessary mental capacity to make a Will. However that is not necessarily the case.
The Court held in Vegetarian Society v Scott  that mental illness alone does not automatically invalidate a will. The issue for the Court to consider is the effect of the mental illness on the testator's mental capacity. The Court held that the testator's thought disorder and schizophrenia did not prevent him from conducting logical thought and goal-directed accomplishments such as the making of a Will.
In the case of Catling v Catling  - where the testator suffered from dementia at the time of making her Will - the court applied the Banks v Goodfellow test and stressed the importance for all Will drafters to:-
- Make comprehensive and adequate file notes when dealing with clients who are elderly or suffer from a mental illness;
- Have due regard for the 'golden rule' that namely when preparing the will of an aged testator or someone who is considered seriously ill, when the will is executed - ie.. that it should be witnessed and approved by an appropriately qualified medical practitioner, who is satisfied of the capacity and understanding of the testator;
- Make comprehensive and adequate file notes where there is a major change in the contents of the will compared to all previous wills, to demonstrate the testator's understanding of the effect of the major differences;
- Choose a competent medical expert.
In the more recent case of Lloyd v Jones and others  a testamentary capacity challenge to the Will of an elderly lady was rejected by the High Court even though the testator had suffered from dementia, confusion, delusions and memory loss.
Where a Will is made therefore by a testator who has mental health issues, that does not mean that a capacity challenge will necessarily succeed. It may be appropriate to question the issue of testamentary capacity but the answer may not be as clear cut as the challenger expects.