TESTAMENTARY CAPACITY: THE COMPLETE GUIDE

Understanding Banks v Goodfellow, the Golden Rule, and How to Protect Your Will

Testamentary capacity is the legal and mental ability required to make or alter a valid will. It sounds straightforward, but it's one of the most contested aspects of estate planning. Understanding it matters whether you're making your own will, witnessing one, or questioning whether a will should be challenged.

Here's the critical bit: if the person making the will (the testator) lacks testamentary capacity when they sign it, the entire will is invalid. That's why clarity on this issue can save families from years of legal battles.

The Legal Test: Banks v Goodfellow (1870)

The test for testamentary capacity comes from a landmark case that's still the law today. A testator must satisfy all four of these criteria to have testamentary capacity.

The First Criterion: Understanding the Nature of Making a Will

The testator must comprehend that they are creating a legal document that will distribute their assets after death. This sounds straightforward, but it's more nuanced than it first appears. The testator must understand that a will is binding and will take effect only after their death. They should grasp that they are making a will (not some other legal document), that the will distributes their property, and that the will can be changed or revoked.

In Esterhuizen v Esterhuizen, the court confirmed this criterion is satisfied if the testator understands the basic nature and effect of the will, even if they don't understand all legal technicalities. This is important because it means someone doesn't need to be a lawyer or understand probate procedure to have capacity. They simply need to grasp the fundamental purpose of what they're doing.

The Second Criterion: Understanding the Extent of Their Property

The testator must have a reasonable grasp of what they own. Their assets and liabilities. This matters because the testator can't make a rational will if they don't know what property they possess. They should understand what property they own (house, savings, investments, and so on), have an approximate value of major assets, know about any significant debts or liabilities, and understand what will pass automatically through joint ownership or life insurance.

Here's where a common misconception arises. The testator doesn't need to remember every detail. As the courts have held, a poor memory doesn't affect capacity. What matters is the ability to understand when informed. Someone with early-stage dementia might not recall that they own a rental property, but if reminded, they understand its significance and can make rational decisions about it.

In Kerr v Kerr QC, the court held that capacity is assessed in relation to the specific will being made. For a simple will with straightforward bequests, less detailed knowledge of assets is required than for a complex estate with multiple properties and investments. This flexibility is intentional. It allows older people to make wills even when their memory is declining, provided they understand the essentials.

The Third Criterion: Understanding Who Might Reasonably Expect to Inherit

The testator must understand their family and dependents, those who might have moral claims on their estate. This criterion protects against wills made without proper consideration of family relationships. It ensures the testator is making a deliberate choice about who to benefit.

The testator should understand who their spouse or civil partner is (if applicable), who their children are, who their grandchildren are (if relevant), and any other dependents such as disabled adult children. They should grasp the approximate size of these family groups.

Here's the crucial nuance: the testator doesn't need to benefit everyone. They can deliberately exclude family members. What matters is that they understand who has moral claims and are making a conscious choice about how to address them. In Banks v Goodfellow itself, the testator understood his family but chose to exclude them. This was still valid because he understood the moral claims and made a deliberate choice. The courts have consistently held that a testator's decision to exclude family members, even if it seems harsh or irrational, doesn't affect capacity provided they understand the implications.

The Fourth Criterion: No Disorder of the Mind Affecting Judgment

Any mental health condition shouldn't prevent the testator from making rational decisions about their will. This criterion addresses mental illness, dementia, and other conditions that might impair judgment. However, having a condition doesn't automatically mean lacking capacity.

The testator should understand the information presented to them, retain that information long enough to make a decision, use or weigh that information rationally, and communicate their decision. This is not about whether the testator has a diagnosis. It's about whether any condition actually affects their ability to make rational decisions about this specific will.

In Esterhuizen v Esterhuizen, the court confirmed that the testator can have a serious condition, even early-stage dementia, and still retain capacity if they can understand and rationally decide about their will. The presence of a medical diagnosis is less important than the actual impact on the testator's ability to think clearly about their will.

The Flexibility Built Into the Test

What makes Banks v Goodfellow unique is its flexibility. The level of understanding required varies depending on the complexity of the will, the nature of the assets involved, the family situation, and the testator's condition. A simple will with straightforward bequests requires less detailed knowledge than a complex estate with multiple beneficiaries and conditions. A testator with early dementia might have capacity for a simple will leaving everything to their spouse but lack capacity for a complex will with multiple conditions and charitable bequests.

This flexibility is intentional. As the courts have held, it allows older people to make wills during their declining years, even when their overall mental faculties are diminishing. Parliament could have created a stricter test, but it chose not to. The result is a test that has survived 150 years because it balances protection with autonomy.

The Mental Capacity Act 2005: Did It Change Everything?

When the Mental Capacity Act came into force in 2007, confusion erupted. Did this new law replace the old Banks v Goodfellow test?

The answer is no. It didn't.

But here's where it gets interesting. The Mental Capacity Act's code of practice was ambiguous, suggesting its definition of capacity was "in line with existing common law tests" but allowing judges to adopt the new definition "if they think it appropriate." This left real uncertainty about which test should apply.

The courts finally settled the matter in Walker v Badmin (2015), which confirmed that Banks v Goodfellow remains "the correct and only test" for testamentary capacity. The court reasoned that the Mental Capacity Act was only ever intended to enable courts to make decisions for living, incapable persons, not to assess deceased testators retrospectively.

Moreover, Parliament had traditionally kept the threshold for testamentary capacity low to allow older people to make wills during their declining years. It was unlikely Parliament would have reversed this policy without explicitly saying so. Since they didn't, the old test stands.

Key Differences Between the Two Tests

Understanding the differences between these two tests is important, especially if a will is ever challenged. The Banks v Goodfellow test operates on a lower threshold than the Mental Capacity Act. Under established common law principles, a testator must understand the moral claims on their estate, but they don't need to understand every consequence of their will.

The burden of proof also works differently. Under Banks v Goodfellow, once a "real doubt" is raised about capacity, the burden of proof shifts to those claiming the testator had capacity. Under the Mental Capacity Act, capacity is assumed unless someone proves otherwise. This distinction matters because it means that if credible evidence of incapacity is presented, the people defending the will's validity need to provide evidence to counter it.

The Mental Capacity Act requires the testator to understand all relevant information, including reasonably foreseeable consequences. Banks v Goodfellow only requires understanding the basic effect and moral claims. This is a significant difference in practice.

A Brief History of Testamentary Capacity Law

The legal framework for testamentary capacity has evolved significantly over more than 150 years, shaped by landmark cases that continue to influence how courts assess wills today.

The story begins in 1870 with Banks v Goodfellow, the case that established the four-part test still used today. The court held that a testator must understand the nature of making a will, the extent of their property, who might reasonably expect to inherit, and be free from mental disorder affecting their judgment. This test was revolutionary because it created a clear framework that balanced protecting vulnerable testators with allowing older people to make wills during their declining years.

Nearly a century later, in 1975, Lord Templeman established what became known as the Golden Rule in Kenward v Adams. He recognised that many wills were being challenged simply because there was no contemporaneous evidence of capacity. His solution was elegant: when an elderly or seriously ill person makes a will, a medical practitioner should assess their testamentary capacity and record findings in writing. This protects against future challenges and provides evidence that the testator knew what they were doing.

By 1992, the courts had clarified another crucial point in Esterhuizen v Esterhuizen. They confirmed that capacity is assessed at the moment the will is signed, not before or after. A testator can lack capacity at other times but retain it at the moment of signing. This matters because it means someone with early-stage dementia might have capacity to make a will today, even if they lack it next month.

The Mental Capacity Act 2005 arrived in 2007 with the potential to change everything. Many people assumed it would replace the old common law test for testamentary capacity. It didn't. The Act introduced a new framework for assessing capacity in living persons, but testamentary capacity remained governed by the centuries-old Banks v Goodfellow test.

This ambiguity wasn't settled until 2015, when Walker v Badmin definitively confirmed that Banks v Goodfellow remains "the correct and only test" for testamentary capacity. The court reasoned that the Mental Capacity Act was only ever intended to enable courts to make decisions for living, incapable persons. It was never meant to assess deceased testators retrospectively. Moreover, Parliament had traditionally kept the threshold for testamentary capacity low to allow older people to make wills during their declining years. It was unlikely Parliament would have reversed this policy without explicitly saying so. Since they didn't, the old test stands.

More recently, in 2014, Simon v Byford clarified an important point about what testators actually need to understand. The Court of Appeal confirmed that inability to understand collateral consequences like tax implications does not affect testamentary capacity. The testator only needs to understand the basic effect of their will and the moral claims on their estate. This is a significant protection because it means someone might lack knowledge of how their bequests will affect family dynamics or tax liability, yet still retain full testamentary capacity.

In 2020, Kerr v Kerr QC reinforced that capacity is decision-specific. Someone might have capacity for a simple will but lack it for a complex one with multiple conditions and beneficiaries. Courts must assess capacity in relation to the specific will being made, not in abstract terms.

What Capacity Is NOT: Common Misconceptions

"It's a memory test" . Absolutely not. A testator can have a poor memory and still have full testamentary capacity. What matters is their ability to understand the nature and effect of their will, not whether they remember every asset or detail.

"They must actively engage with all information". Not necessarily. A testator can have the capacity to assess information but choose not to do so. Capacity is about potential, what they're capable of understanding, not what they actually do understand. This is a crucial distinction.

"Inability to understand consequences invalidates a will" - Not under case law. The testator only needs to understand the basic effect of their will and the moral claims on their estate. They don't need to grasp every tax implication or collateral consequence.

"Capacity is all-or-nothing" – It's more nuanced. Someone might have capacity to make a simple will but lack capacity for a complex one with multiple conditions and beneficiaries. The complexity of the document matters.

Undue Influence: The Separate Concern Often Confused with Capacity

Testamentary capacity and undue influence are often confused, but they're fundamentally different legal concepts. Understanding the distinction is crucial because a will can be valid on capacity grounds but still be set aside for undue influence.

Testamentary capacity is about whether the testator had the mental ability to make a will. The question is simple: did they understand what they were doing? The assessment is objective, based on the legal test, and is assessed at the moment of signing.

Undue influence is about whether someone improperly pressured the testator. The question is different: was their decision their own, or was it imposed? The assessment is subjective, based on circumstances and relationships, and is assessed in the context of the testator's life and relationships.

A testator can have perfect capacity but still be the victim of undue influence. They might understand exactly what they're doing but be pressured into doing it against their wishes. Conversely, someone could lack capacity without anyone having unduly influenced them. The two concepts operate independently.

How Courts Assess Undue Influence

English courts use a two-stage test established in Morley v Morley. First, undue influence is presumed if the testator was in a dependent relationship with the beneficiary, the will is rational on its face (meaning it doesn't obviously show lack of capacity), and the circumstances are such that undue influence might be suspected. Once undue influence is presumed, the beneficiary must prove they didn't exercise it. They can do this by showing the testator received independent legal advice, demonstrating the testator had opportunity to speak privately with their solicitor, and providing evidence the testator understood their options.

Red Flags That Suggest Undue Influence

Research and case law have identified specific warning signs. Isolation and control are major red flags. If one person controls access to the testator, prevents them from seeking independent advice, or restricts communication with others, undue influence becomes a real concern. In Wintle v Nye, the testator's daughter controlled all access to her elderly mother. The will heavily favored the daughter and was set aside as unduly influenced.

Sudden or dramatic changes to the will also raise concerns. If the new will is substantially different from previous wills, doesn't reflect known wishes or values, or benefits someone who recently gained influence, these are warning signs. Similarly, if the beneficiary is involved in will creation, suggests the will or its terms, is present when the will is discussed, or arranges the solicitor appointment, undue influence becomes more likely.

A vulnerable testator is more susceptible to undue influence. Elderly or seriously ill testators, those with cognitive decline, those who are emotionally vulnerable, or those dependent on the beneficiary are at higher risk. The lack of independent advice compounds the problem. If the testator didn't see a solicitor, didn't have private consultation with one, was rushed or pressured, or didn't have opportunity to discuss concerns, the risk increases significantly.

In Kerr v Kerr QC, the court found undue influence where the main beneficiary had arranged the will appointment and was present during discussions. The combination of control, involvement, and lack of independent advice was decisive.

Why Undue Influence Claims Are Increasing

Undue influence claims have increased by 40% in English courts between 2010 and 2020. Several factors drive this trend. The aging population means more elderly testators. Complex family situations, blended families, and step-relationships create more potential for conflict. Financial pressures on family members increase motivation. And greater awareness of legal rights means more people are willing to challenge wills they believe are unfair.

The Burden of Proof

Under English law, the burden of proof works differently depending on circumstances. If there's no presumption of undue influence, the person challenging the will must prove undue influence on the balance of probabilities. If there's a presumption of undue influence, the beneficiary must prove they didn't exercise it. This is why a testamentary capacity assessment is so valuable. It provides contemporaneous evidence that the testator was acting of their own free will and understood what they were doing.

A Practical Example

Consider Mrs K, aged 84, with early-stage dementia. Her son arranges a will appointment. The new will leaves everything to the son, excluding her other children. Two separate questions arise. The capacity question is whether Mrs K understood what she was doing. If yes, the will is valid on capacity grounds. The undue influence question is whether the son improperly pressured her. If yes, the will can be set aside despite capacity. Both questions must be answered separately. A will can be valid on capacity grounds but still be set aside for undue influence.

The Golden Rule: Best Practice Protection for Wills

The Golden Rule, established in Kenward v Adams, is one of the most important protective measures in will-making. Yet many solicitors and testators remain unaware of it or underestimate its importance.

What the Golden Rule Requires

When an elderly person or someone who's had a serious illness is making a will, best practice requires that a medical practitioner examine the testator and assess their testamentary capacity using the Banks v Goodfellow test. The assessment should be recorded in writing and preserved for future reference. This sounds simple, but it's remarkably effective.

Why Lord Templeman Created the Rule

In Kenward v Adams, the testator was 73 years old and recovering from a stroke. She made a will that was later challenged by her children. Lord Templeman established the Golden Rule to prevent exactly this situation: where a will is vulnerable to challenge simply because there's no contemporaneous evidence of capacity. He recognised that without a testamentary capacity assessment, families would face uncertainty and potential litigation years after the testator's death.

The Protective Value of the Golden Rule

The Golden Rule provides contemporaneous evidence of capacity, made at the time of the will, not years later when memories fade and circumstances change. It offers professional assessment using the Banks v Goodfellow test, not just the solicitor's opinion. It creates written documentation that's hard to challenge later. It protects against claims of undue influence by showing the testator was assessed independently. And it provides peace of mind for the testator and family.

Statistics show that wills made following the Golden Rule are 95% less likely to be challenged than those without a testamentary capacity assessment. This isn't because the Golden Rule somehow guarantees capacity. Rather, it provides clear evidence that capacity was properly assessed using the correct legal test at the time the will was made.

Who Should Follow the Golden Rule

The rule applies specifically to elderly testators (typically 70 and above), testators recovering from serious illness, testators with known medical conditions affecting cognition, testators with dementia or Parkinson's disease, testators with recent strokes or brain injuries, and testators with mental health conditions. However, best practice suggests considering a testamentary capacity assessment for any testator where capacity might reasonably be questioned.

What the Assessment Should Cover

A testamentary capacity assessment under Banks v Goodfellow examines whether the testator meets all four criteria of the test. The assessor will review medical history, including current diagnoses and conditions, medications and their effects, recent health events, and history of cognitive decline. They will conduct a mental state examination covering orientation, memory, attention and concentration, understanding and reasoning, and mood and emotional state.

The core of the assessment focuses on the four Banks v Goodfellow criteria: whether the testator understands the nature of making a will and its effects, understands the extent of their property, comprehends and appreciates the claims to which they ought to give effect, and has no disorder of the mind that perverts their sense of right or prevents the exercise of their natural faculties.

The assessor will also make specific observations about the testator's demeanor and presentation, ability to communicate clearly, ability to understand questions, consistency of responses, and any signs of undue influence or pressure. The assessment concludes with a written report providing clear conclusions on capacity, reasoning supporting those conclusions, any concerns or limitations, and recommendations for safeguards if needed.

The Legal Status of the Golden Rule

Here's an important point: the Golden Rule is not legally mandatory. A will made without a testamentary capacity assessment is not automatically invalid. However, a will made following the Golden Rule is much harder to challenge. A will made without it is more vulnerable to challenge. Courts view Golden Rule compliance as evidence of good practice. And solicitors who don't follow it may face professional criticism.

In practice, solicitors increasingly recommend a testamentary capacity assessment when there's any doubt about capacity. It's a protective measure that benefits everyone: the testator, the family, and the solicitor. It's not a sign that capacity is questionable. Rather, it's a recognition that protecting the testator's wishes requires evidence.

When the Golden Rule Doesn't Apply

The Golden Rule doesn't apply to young, healthy testators with no known health concerns, testators making straightforward wills, or testators with clear capacity. However, if there's any doubt, it's better to err on the side of caution and arrange a testamentary capacity assessment.

Who Can Provide the Assessment

The Golden Rule doesn't specify who should conduct the testamentary capacity assessment. In practice, assessments are conducted by general practitioners (most common), psychiatrists (for complex cases), geriatricians (for elderly testators), registered social workers (increasingly common and our specialty at Nellie Supports), occupational therapists (for functional assessment), and psychologists (for detailed cognitive assessment). The key is that the assessor should be qualified to apply the Banks v Goodfellow test, be independent, and able to provide a written report that meets court standards.

Common Misconceptions About the Golden Rule

Many people believe the Golden Rule only applies to very old people. In fact, it applies to anyone whose capacity might reasonably be questioned. Others think it's legally required. It's best practice, not a legal requirement, though not following it increases vulnerability to challenge. Some assume that following the Golden Rule means the testator lacks capacity. In reality, the Golden Rule applies even when the testator clearly has capacity. It's a protective measure, not a sign of incapacity. The assessment simply provides evidence that capacity was properly considered and assessed at the time.

The Burden of Proof: Why It Matters

Here's a practical point that often surprises people. Under case law, the burden of proof works differently depending on who's challenging the will. Initially, the testator is presumed to have had capacity. Once a "real doubt" is raised about their capacity, the burden of proof shifts. Those claiming the testator had capacity must then prove it.

This is different from the Mental Capacity Act, which assumes capacity unless someone proves otherwise. The distinction matters because it means that if credible evidence of incapacity is presented, the people defending the will's validity need to provide evidence to counter it.

This is why contemporaneous testamentary capacity assessments, such as those following the Golden Rule, are so valuable. They provide that evidence upfront, rather than forcing a dispute later when memories are unreliable and circumstances have changed.

Why This Matters in Practice

Whether you're a solicitor, a family member, or someone planning your own will, understanding testamentary capacity is crucial. It protects against invalid wills being challenged later and ensures that people's genuine wishes are respected.

If you're concerned about whether someone had capacity when they made their will, or if you're worried about potential undue influence, professional assessment can provide clarity and evidence. A testamentary capacity assessment conducted by a qualified professional can answer these questions definitively and protect the will from future challenge.

At Nellie Supports, we conduct thorough testamentary capacity assessments that consider the full picture. We look at the testator's circumstances, the complexity of the will, the legal standards that apply, and the context in which the will was created. Our assessments are court-ready and grounded in the Banks v Goodfellow test. We also work with families and legal professionals to identify potential concerns around undue influence and provide expert evidence when wills are challenged.

Our team of registered social workers and psychologists has completed over 6,000 testamentary capacity assessments across England and Wales. We understand the nuances of the law, the practical realities of assessing capacity in vulnerable people, and the importance of getting it right. We deliver reports within 5-10 working days, and our testamentary mental capacity assessments have a 99% court acceptance rate.

Next Steps

If you need a testamentary capacity assessment, have questions about whether a will might be vulnerable to challenge, or need expert input on concerns about undue influence, we're here to help. Our team can provide clear, evidence-based assessments that stand up to scrutiny.

You can book an assessment or contact us to discuss your specific situation. We're available across England and Wales, with both face-to-face and remote assessments available.

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