This guide is maintained as a current resource for September 2026 and covers only the laws of England and Wales. Information is for general guidance, not legal advice. Consult a qualified solicitor for advice specific to your situation.
Learn how courts in England and Wales assess lack of capacity claims in will disputes. This comprehensive guide explains the legal standards, the Banks v Goodfellow test, evidence requirements, procedural steps, and what constitutes testamentary capacity, with clear practical guidance for readers.
In England and Wales, a will must reflect the clear, independent intentions of the person signing it (the testator). A common ground to challenge the validity of a will in contentious probate is that the testator lacked the mental capacity to make that will at the relevant time. Lack of capacity claims involve specific legal standards and evidence, and they are typically fact‑intensive. Courts assess these claims using established legal tests and principles to decide whether the will should stand or be set aside.
This article explains how courts assess lack of capacity claims in will disputes, what legal standards apply, what evidence is relevant, typical procedures, and practical considerations for anyone involved in or preparing for such claims. It is designed to be accessible to members of the public, students, and solicitors.
What Does “Capacity” Mean in a Will Context?
Testamentary capacity refers to a person's mental ability to make a valid will. It is different to general legal capacity in other contexts (such as managing finances) and has its own specific criteria under established case law.
Capacity is assessed based on the person's state of mind at the time the will was made (both when instructions are given and at execution). The question is whether, at that specific time, the testator had sufficient understanding to create a valid testamentary disposition.
The Legal Test: Banks v Goodfellow
The Applicable Framework
For lack of capacity claims, the courts in England and Wales apply the common law test established in Banks v Goodfellow (1870). A 2024 decision in Leonard v Leonard confirmed that this traditional test remains the sole legal standard for testamentary capacity assessments in probate cases.
The Banks v Goodfellow test requires that, at the time of making the will, the testator must:
- Understand the nature of the act and its effects: The testator must appreciate that they are making a will that determines how their property is distributed on death.
- Understand the extent of their property: They must have a general understanding of the nature and value of their estate.
- Comprehend and appreciate potential claims on their estate: The testator should be able to recognise those who might reasonably expect to benefit.
- Be free of any disorder of the mind or delusion that influences the terms: Any mental disorder must not have ‘poisoned' the testator's affections or distorted their judgment such that it affected dispositions.
These criteria do not require the testator to have expert legal or financial knowledge; rather, they must demonstrate basic understanding and reasoning about the will and its effects.
Capacity vs Other Legal Tests
There has been debate about whether the Mental Capacity Act 2005 (MCA) should apply to testamentary capacity. The MCA sets out a statutory framework for assessing capacity in general decision‑making. However, case law confirms that the MCA does not replace Banks v Goodfellow for wills. The MCA can be used as a cross‑check or for substantive guidance, but it is not the test that determines whether a will is valid.
Evidence in Lack of Capacity Claims
Lack of capacity claims require evidence that demonstrates the testator did not meet the Banks v Goodfellow criteria. Since the testator is deceased, evidence is generally retrospective and may include:
Medical and Clinical Evidence
Contemporaneous medical records (for example, diagnoses of dementia, delirium, or other cognitive impairment) are central. Evidence should relate to the relevant time when the will was made, not only before or after.
Medical expert reports that analyse cognitive function can be persuasive, though they are not determinative on their own.
Solicitor and Professional Notes
Detailed notes from meetings with the solicitor or will‑drafter, including questions asked and responses given, can be significant. Good practice (sometimes called the “golden rule”) involves having a medical practitioner present to confirm capacity if there are concerns. However, this is not legally conclusive; it is guidance that supports evidence of capacity if followed.
Witness and Family Evidence
Testimony from family members, carers, and witnesses about the testator's behaviour, communication, and understanding when giving instructions can be important. Evidence may include observed confusion, inability to discuss the will logically, or inconsistent reasoning.
Evaluation of Delusions
If the testator suffered from delusions or beliefs unrelated to the will that nevertheless influenced their dispositions, courts will examine whether such delusions distorted decisions. For example, if a testator made irrational bequests because of unfounded beliefs about beneficiaries, this may support lack of capacity.
No Presumption of Lack of Capacity
Courts do not automatically assume incapacity simply because the testator was elderly, ill, or had a diagnosis of dementia. A person with cognitive impairment can still have testamentary capacity if they meet the Banks v Goodfellow criteria at the relevant moment.
On the other hand, a will that appears rational on its face or was prepared by an experienced solicitor may attract a presumption of capacity. This affects how robust the evidence must be for a claimant to succeed.
Threshold of Proof
In probate disputes, the claimant - the person alleging lack of capacity - bears the burden of proof. The standard is the balance of probabilities, meaning it must be more likely than not that the testator lacked capacity. This requires cogent evidence linking the testator's mental state to the Banks v Goodfellow criteria.
Procedural Considerations
Timing of a Claim
A claim challenging a will on the basis of lack of capacity must generally be raised promptly after the grant of probate. Interested parties often lodge a caveat to prevent probate being granted until the dispute is resolved, and then issue a claim form in the appropriate court. Courts can extend time to challenge where there are good reasons for delay.
Legal Costs and Risks
Because lack of capacity claims can be complex and evidence‑heavy, costs can escalate. Courts may consider costs consequences if a party unreasonably pursues or resists a claim. Expert evidence can be a significant component of cost.
Common Misconceptions
It Is Not a Memory Test
The issue is not whether the testator had perfect memory. The courts are concerned with capacity to make a will at that time, not memory recall in general. A testator can suffer some memory issues but still have testamentary capacity.
Odd or Unfair Provisions Do Not Automatically Mean Lack of Capacity
A will can be unusual, inequitable, or unfair to certain beneficiaries and still be valid. As long as the testator understood what they were doing and met the legal criteria, the content of the will is not invalid simply because it appears unreasonable.
Key Takeaways
In England and Wales, lack of capacity claims in will disputes turn on whether the testator had testamentary capacity at the time the will was made. The courts apply the Banks v Goodfellow test, which focuses on understanding the nature of making a will, the extent of the estate, potential beneficiaries' claims, and freedom from any mental disorder that affects judgment.
Capacity evidence is retrospective and requires a range of information from medical records, solicitor notes, expert testimony, and witness accounts. The burden of proof is on the claimant, and odd or unconventional distributions do not, by themselves, prove incapacity.
Understanding how the courts assess capacity claims is essential in contentious probate. Prompt action, detailed evidence, and appropriate legal preparation are key factors in navigating these challenging disputes.
