Thursday, 12th March 2026

Testamentary Capacity Revisited: Practical Lessons from the case of Ginger v Mickleburgh

In the recent case of Ginger v Mickleburgh the High Court revisited the fundamental principles relating to testamentary capacity (the capacity to make a Will). It provides a useful reminder of the importance of timely and thorough capacity assessments in will-preparation.

Case Overview

The dispute concerned a 2014 will (the ‘Will’) made by the late Michael Gwilliam which was challenged by his four daughters. One of the grounds for the challenge was a lack of testamentary capacity.

The Will

The Will gave:

• 75% of Mr Gwilliam’s estate to his sister, nephews and ex-partner; and
• 25% to his four daughters in equal shares.

This was a significant shift from the Testator’s previous wish that his estate should pass to his children on intestacy.

The Testator’s condition

At the time the Will was executed Mr Gwilliam was suffering from late-onset schizophrenia with delusions. The Court found that those delusions materially affected his decision-making and prevented him from properly appreciating the nature and effect of his testamentary dispositions.

The Decision

The Will was therefore held to be invalid for lack of testamentary capacity, and Mr Gwilliam was treated as having died intestate.

Core Legal Principles

The Court confirmed that the applicable test for testamentary capacity remains the one set out in Banks v Goodfellow (1869).  A testator must be able to:

1. understand the nature and effect of making a will;
2. understand the extent of their property;
3. comprehend and appreciate the claims to which they ought to give effect (such as the expectations of close family); and
4. not be subject to a disorder of the mind that poisons their affections, perverts their sense of right, or prevents the exercise of natural faculties.

Application of Legal Principles

The Court, in this case, held that Mr Gwilliam failed the third and fourth limbs of the Banks v Goodfellow test.

At the time the Will was executed, Mr Gwilliam held several false and irrational beliefs about his daughters, including claims that they were conspiring with their mother to have him sectioned under the Mental Health Act to facilitate the sale of his home. The Judge was satisfied that these beliefs constituted delusions and that, but for those delusions, Mr Gwilliam would not have executed the Will.

Considering these delusions, the Court held that Mr Gwilliam could not properly consider the claims of his daughters. The Court emphasised that the ability to ‘comprehend and appreciate’ the claims of others requires a testator to have the capacity to evaluate those claims rationally. It is not sufficient merely to remember who potential beneficiaries are.

The role of solicitor evidence and the “golden rule”

The Will was prepared by an experienced paralegal who considered Mr Gwilliam to have capacity at the time the Will was executed.  However, there was no formal, contemporaneous medical capacity assessment.

The Court recognised that an assessment of capacity carried out by an experienced legal practitioner may carry significant weight.  However, much depends on the circumstances in which instructions are taken and the practitioner’s knowledge of the testator and their circumstances.

In this case, the Court emphasised that the paralegal had no prior relationship with Mr Gwilliam, and was aware of his recent sectioning under the Mental Health Act. The Court reiterated the “golden (if tactless) rule” that in cases of advanced age or infirmity, a doctor – ideally the testator’s own – should examine and attest to capacity. The paralegal ought to have known better.

Key Take-Away for Families

Families often treat estate planning as a to-do task that they never quite around to completing. Even in simple circumstances, where the intestacy rules will achieve their goals, families should still consider preparing a Will. A professionally prepared Will is often future-proofed, where possible, and will help to avoid stress and uncertainty if an individual later loses capacity.

Where an individual has had medical intervention for mental health difficulties, and wishes to make a Will, families should be prepared to facilitate a capacity assessment. Without one, any Will made is susceptible to challenge.

If you have any queries regarding this note or require further information about anything covered in it, do get in touch with Alex Shah or Henry Braithwaite in our specialist Private Client team or your usual contact at the firm on +44 (0)20 7526 6000.