When an individual has executed a will in the last months or even weeks of life, it may not be until the individual’s death that family members become aware that a Will was made during suspected or confirmed incapacity. 

The person making a Will must be of ‘sound mind, memory and understanding’ when they made it. The law relating to whether a person has the sufficient mental capacity to understand the content of their Will was established in the case of Banks v Goodfellow [1869-70], which stated that the testator must:

• Be free from any delusion of the mind.
• Understand the nature of the act and its effects.
• Comprehend the extent of the property of which they are disposing.
• Be aware of the persons for whom they would usually be expected to provide.
• Not be affected by any ‘disorder of the mind’ that would affect their dispositions to those people.

The law does not call for a perfectly balanced mind just because a person making a Will did not have the capacity to execute a Will. The question as to whether a person has the relevant mental ability is a factual question which is often determined by medical evidence. However, the evidence of close friends and family is also relevant, and a person can be found to be lacking mental capacity based upon their evidence alone. 

Most commonly, a diagnosis of dementia will give rise to a concern that the individual did not possess the required capacity to execute a Will. In such patients, it is often the case that on some days, they understand matters, but their memory is lacking on other days. It should be noted, however, that a diagnosis of dementia will not, in itself, result in an inability for a person to execute a Will. To succeed in contesting a Will, it must be shown that when the Will was executed, the testator did not have the capacity to make a will. 

The extent of the effect of dementia on the individual should be considered when the Will is prepared. If the Will writer is concerned the individual does not have the capacity, then a report from a medical professional should be obtained to provide an opinion on the individual’s ability, commonly referred to as ‘the Golden Rule.’

The Golden Rule, however, is a suggestion and not a requirement, and the absence of a medical report will not in itself mean that a will is not valid on the grounds of incapacity. On the other hand, a court can find that an individual lacked capacity even where a medical report has been obtained.

Where a Will is successfully disputed, and the court confirms the will is invalid, if there is not an earlier valid Will, then the testator’s estate will be distributed according to the intestacy rules.