The problem

The policies of former UK prime minister Margaret Thatcher led to an increase in property ownership in the UK. Given the steep rise in house prices in Britain since she left office, more people now have substantial estates to bequeath. Alongside this trend has been an increase in the proportion of older people in the population, resulting in a growth in the prevalence of dementia. Dementia and will making are awkward bedfellows. This would scarcely be a problem if people were to make wills before reaching old age, but this often does not happen, and a growing number of wills are challenged after the testator's death. Much litigation could be avoided, however, if doctors, when asked by solicitors, assessed testamentary capacity correctly.

Defining testamentary capacity

The most important fact about capacity is that it is task specific. Incapacity to manage one's financial affairs does not necessarily imply, for example, incapacity to donate power of attorney. The leading authority on testamentary capacity is the judgment in the case of Banks v Goodfellow.1 This judgment remains the test in most common law jurisdictions today and is stated thus:

“It is essential . . . that a testator [1] shall understand the nature of the act [of making a will] and …