Poisoning of the mind: The high bar to succeed in fraudulent calumny

Inheritance disputes can often be complex and emotionally charged, particularly those involving challenges to the validity of wills. It is also common to hear concerns about the influence exerted on vulnerable testators, which can result in claims of fraudulent calumny. 

A recent High Court case in which we acted – Ginger v Mickleburgh [2026] EWHC 100 (Ch) – highlights just how demanding the court can be when asked to scrutinise allegations of wrongdoing in the making of a will. Our inheritance & trusts disputes experts Claire Cox and Tom Gordon share their insight.

Case summary and outcome

In this case, we represented four sisters who were collectively left 25% of their father’s estate to be divided equally between them, pursuant to his 2014 will. They sought to challenge that will on multiple grounds, including testamentary capacity and fraudulent calumny – a rarely invoked but increasingly discussed doctrine concerning the “poisoning of the testator’s mind” through false statements made with dishonest intent. To succeed, one must demonstrate that the false statements were made knowing they were untrue or not caring whether they were true – with the aim of reducing or removing that person’s inheritance.

Ultimately, the sisters succeeded in setting aside the will on the basis that the deceased lacked testamentary capacity. The court concluded that at the time the will was executed, the deceased was suffering from an insane delusion or disorder of the mind. Judge Blohm found against the purported will and declared the deceased died intestate. The sisters’ claim based on fraudulent calumny, however, did not succeed. In reaching that conclusion, Judge Blohm made a number of important observations on the scope and evidential threshold of the doctrine.

Fraudulent calumny

The sisters alleged that two of the defendants, Sheila Gwilliam and Joan Brooks, had poisoned the deceased’s mind against them so as to induce him to make a will less favourable to them. A number of statements attributed to Sheila and Joan were admitted in evidence and found to be proven by the court. However, the court found that “however unreasonable” the belief, where a person genuinely holds the opinion they express, it cannot be said to be falsely made for the purposes of fraudulent calumny.

The court accepted that Sheila and Joan were motivated by a desire to influence the deceased to make a will that disadvantaged his children. Motivation alone, however, was insufficient. To satisfy the test for fraudulent calumny, the statements must not only be false but must also be made with knowledge of their falsity or with reckless indifference to the truth.

Judge Blohm summarised the position succinctly:

“Where a party genuinely believes that which they say is true, they cannot be fraudulent, however unreasonable or untethered from reality their statement is from the truth.”

This highlights a critical element of the doctrine. Even where statements are judged to be false, a claim in fraudulent calumny will fail if the person making them genuinely believed them to be true. The court accepted that, but for the intervention of the defendants, the deceased would not have made the will in question or would not have excluded the claimants. Nevertheless, without proving the defendants knew these statements to be false or that they were reckless, fraudulent calumny cannot be made out.

What does this mean?

For practitioners, advisers and families, this case is a powerful illustration of both the high bar required to establish fraudulent calumny and the Court’s careful, inquisitorial approach to testamentary disputes. Even where influence, hostility or unfairness is present, the law demands clear evidence of dishonesty before it will interfere with a testator’s freedom to dispose of their estate.

When suspicions arise over the circumstances of a will, early legal advice, thorough evidence gathering and a realistic assessment of the available proof are essential. In a field where family dynamics can be complex and motivations mixed, the Court’s message is clear: fraudulent calumny requires more than influence, it requires proof of deliberate falsehood.

Ultimately, Ginger v Mickleburgh serves as an important reminder of the complexities that often lie beneath the surface of inheritance disputes. While the doctrine of fraudulent calumny remains notoriously difficult to establish, the case demonstrates the willingness of the court to intervene where testamentary capacity is genuinely in doubt.

Our Legal 500-rated inheritance & trusts disputes team offer friendly but practical advice on this complex area of law.