Background: Challenges to Wills on the basis of lack of testamentary capacity are likely to increase due to a combination of economic factors, high prevalence of mental disorders in old age and the complexity of many modern families. Geriatric psychiatrists and other experts will be asked to provide expert assessment of the testamentary capacity of individuals whose Wills are being challenged retrospectively. The traditional criteria described in the Banks vs Goodfellow case have been held as the standard for testamentary capacity. However, these criteria may not be comprehensive enough for the coming generation of expert assessors.
Method: The literature and selected international case law relevant to testamentary capacity were reviewed. Particular focus is placed on the conceptual and empirical approaches to the assessment of complex capacities that may inform the development of specific legal standards. In addition, 25 consecutive medico-legal reports on retrospective testamentary capacity were analyzed according to co-morbid medical and psychiatric disorders as well as psychosocial and behavioural variables. Illustrative case vignettes are included.
Results: The typical profile for retrospective challenges to testamentary capacity included a radical change from a previous Will (72%), where undue influence was alleged (56%), in a testator with no biological children (52%), who executed the Will less than a year prior to death (48%). Co-morbid conditions were dementia (40%), alcohol abuse (28%) and other neurological/psychiatric conditions (28%).
Conclusions: While Banks vs Goodfellow continues to provide a sound basis for assessing testamentary (task-specific) capacity, the complexity and subtlety of the issues reflected in these cases highlight the need to go beyond the traditional criteria and assess situation-specific factors. Expert assessors need to determine whether the testator appreciated the consequences of executing or changing a Will, especially when there has been a radical change in the context of a complex or conflictual family environment. Empirical studies addressing the cognitive functions relevant to testamentary capacity and the development of legal standards based on a competency construct may also help to inform retrospective capacity assessments.