Fellow practitioners will be familiar with equity’s protection of the vulnerable from exploitation, including by developing the doctrine of the ‘presumption of undue influence’ in respect of certain lifetime transactions.
By way of reminder, such a (rebuttable) presumption arises where (i) the complainant placed trust and confidence in the other party in relation to the management of the complainant's financial affairs; and (ii) the transaction, entered into allegedly by reason of undue influence, calls for some explanation.
The Courts will go further in certain cases, adopting (to employ the words of Nicholls LJ in Royal Bank of Scotland Plc v. Etridge (No 2)  2 AC 773) “a sternly protective attitude towards certain types of relationship in which one party acquires influence over another who is vulnerable and dependent and where, moreover, substantial gifts by the influenced or vulnerable person are not normally to be expected.” Thus, an irrebuttable presumption of undue influence will arise if there is a certain relationship – such as a medical adviser and patient – and the transaction entered into calls for some explanation.
How does it operate?
The basis of the Court’s interference is not, however, as it is often understood, because of a wrongful or dishonest act on the part of the defendant; rather, as Mummery LJ explicated in Pesticcio v Huet  EWCA Civ 372, it is a matter of public policy to prevent the presumed influence arising from the relationship of trust and confidence being abused.
Such is the recognition of the need for the Courts’ protection, that it is not essential that the transaction should be disadvantageous to the pressurised or influenced person, either in financial terms, or in any other way (CIBC Mortgages Plc v Pitt  1 AC 200).
In light of the above, it is striking that a similar presumption, based on the same public policy reasoning, does not exist for testamentary dispositions. In my practice, I often come across scenarios where a vulnerable and isolated elderly person has made a substantial testamentary gift to an (often self-appointed) “friend”" or “carer” in highly suspicious circumstances; however, clients in such scenarios (typically the testator’s loved ones) do not feel able to challenge the purported will’s validity on the grounds of undue influence, given the difficulties, and the cost risks, of proving such a claim.
It appears arbitrary that, if this gift were made in the testator’s lifetime, then the scales of justice would be weighted in my clients’ favour. Moreover, the need for a presumption of undue influence in the testamentary context is arguably more necessary, as Dennis Klinck has perceptively argued (“Does the presumption of undue influence arise in the testamentary context?” (2005) 24 Estates, Trusts and Pensions Journal 125), because the victim will likely be dead by the time the (purported) bequest comes to light, they are less likely, than in the case of a (purported) lifetime gift, to expose those who have exploited them.
It appears all the more odd that such a presumption does not arise in the testamentary context in light of the fact that if there is a question about the testator’s (lack of) testamentary capacity, the burden of proof will be shifted to the person seeking to propound the validity of the will if a real doubt is raised about this (Key v Key  EWHC 405 (Ch)). For example, as in Key itself, if the testator is old, infirm, grieving, and the will is a radical departure from the previous one in favour of persons who had provided care for a short period of time, the burden will be shifted.
The Law Commission has recognised the need for a suitably confined test for a presumption of undue influence to arise in the testamentary context, with various questions pertaining to this being put out to public consultation in 2017. However, the results of this are yet to be reported.
The country’s (and indeed the world’s) response to the pandemic, retreating into their homes to prevent the spread of covid-19, emphasised the importance of protecting the most vulnerable in our society. We must not forget that the vulnerable need – to borrow Nicholls LJ’s words – the “stern protection” of the law in the context of their testamentary wishes, too.
Emily Bueno is an associate at Mishcon de Reya LLP: mishcon.com