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Capacity Assessment

Also known as: Mental Capacity Assessment, Capacity Test

Definition

A capacity assessment is a formal evaluation by a solicitor, doctor, or both to determine whether someone has the mental ability to make a specific legal decision at a particular time.

Understanding capacity assessment is crucial because documents like wills and Lasting Powers of Attorney can be challenged and declared invalid if the person lacked capacity when signing.

What Does Capacity Assessment Mean?

Capacity assessment is the formal process of evaluating whether someone has the mental ability to make a specific legal decision—such as creating a will, appointing an attorney under an LPA, or selling property. The assessment examines whether any impairment or disturbance in brain or mind function prevents the person from understanding, retaining, using, or communicating information relevant to that particular decision. Capacity is both decision-specific (ability varies depending on the decision's complexity) and time-specific (can fluctuate hour-by-hour or day-by-day with conditions like dementia).

Two main legal frameworks govern capacity assessment in England and Wales. For wills, assessors apply the Banks v Goodfellow test from 1870, which requires understanding the nature and effect of making a will, comprehending the extent of property, appreciating who has moral claims on the estate, and being free from mental disorder that distorts judgment. For Lasting Powers of Attorney and most other decisions, the Mental Capacity Act 2005 provides the statutory framework through its two-stage test: first, is there an impairment of mind or brain? Second, does that impairment prevent the person from understanding, retaining, using, or communicating the decision? The MCA's four abilities test examines whether someone can understand relevant information, retain it (even briefly), use and weigh it to make a decision, and communicate that decision by any means.

Capacity assessments serve multiple critical purposes. They protect vulnerable people from exploitation or making decisions they don't truly understand. They provide contemporaneous evidence that defends against future legal challenges—though medical evidence doesn't guarantee validity, as courts can still overturn documents based on other evidence. Solicitors have a professional duty to assess capacity and refuse to proceed if capacity is lacking, with the "Golden Rule" requiring medical evidence when clients are elderly, seriously ill, or show signs of confusion.

Who conducts the assessment depends on the situation's complexity. For straightforward cases, solicitors assess capacity by asking detailed questions about assets, family structure, and the client's intentions, then documenting observations thoroughly in attendance notes. When vulnerability indicators arise—advanced age, dementia diagnosis, sudden changes in testamentary plans, or family concerns—solicitors should obtain medical evidence. GPs who know the patient well may provide adequate capacity opinions for simple cases, but independent medical experts with specialist capacity training provide more robust evidence for high-value estates or anticipated disputes. The collaborative approach, with both legal and medical professionals assessing capacity from their respective perspectives, offers the strongest protection. Medical assessments typically cost £500-£2,500 for independent experts, a worthwhile investment when substantial assets or family disputes are at stake.

Common Questions

"When is a capacity assessment needed for a will?" A capacity assessment is typically needed when there's doubt about whether someone understands the nature of making a will, the extent of their assets, and who should benefit. Solicitors should follow the "Golden Rule" and obtain medical evidence when clients are elderly, seriously ill, or show signs of confusion. Specific triggers include dementia diagnosis, cognitive impairment, sudden unexplained changes to long-standing testamentary plans, or family members expressing concerns about undue influence.

"What's the difference between capacity assessment for a will versus an LPA?" Will capacity (testamentary capacity) is assessed using the 1870 Banks v Goodfellow test, focusing on understanding the will's nature, assets, and beneficiaries. LPA capacity uses the Mental Capacity Act 2005 two-stage test, requiring understanding of the LPA's effect, attorney powers, when they can act, and what assets they'll manage. The LPA test is generally considered more stringent because donors must understand more complex concepts about delegating decision-making authority.

"Who can conduct a capacity assessment?" Capacity assessments can be conducted by solicitors (who observe and document the client's understanding), medical professionals (GPs, psychiatrists, or specialists in capacity assessment), or ideally both working together. For complex cases or high-risk situations, an independent medical expert with specific training in capacity assessment is strongly recommended to provide robust evidence that can withstand court scrutiny if challenged.

Common Misconceptions

Myth: If a doctor says someone has capacity, the will can't be challenged

Reality: Medical evidence doesn't guarantee a will's validity. Courts have confirmed that even when the "Golden Rule" was meticulously observed with medical assessment at the time of signing, wills can still be declared invalid based on other evidence. Medical opinions from GPs without specialist capacity training are particularly vulnerable to challenge in contested probate proceedings.

Myth: Capacity assessment for a will uses the Mental Capacity Act 2005

Reality: Testamentary capacity (will-making capacity) is assessed using the common law Banks v Goodfellow test from 1870, NOT the Mental Capacity Act 2005. The MCA applies to LPAs, property decisions, medical treatment, and most other decisions—but wills remain governed by the older common law test, which has different requirements. Courts have definitively confirmed that Banks v Goodfellow remains the correct and only test for testamentary capacity.

  • Mental Capacity: The underlying state being evaluated—capacity assessment is the process that determines whether someone has mental capacity for a specific decision.
  • Testamentary Capacity: The specific type of capacity that capacity assessments evaluate for wills, using the four Banks v Goodfellow requirements.
  • Mental Capacity Act 2005: The statutory framework providing the two-stage assessment test for LPAs and most decisions except wills.
  • Banks v Goodfellow Test: The common law standard that capacity assessments apply when evaluating someone's ability to make a valid will.
  • Court of Protection: The court that resolves disputed capacity assessments and authorizes statutory wills when capacity is lacking.

Need Help with Your Will?

Understanding capacity assessment is essential for ensuring your will's validity. If you or a loved one has concerns about mental capacity, proper assessment and documentation now can prevent costly disputes later.

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Legal Disclaimer:

This article provides general information only and does not constitute legal or financial advice. WUHLD is not a law firm and does not provide legal advice. Laws and guidance change and their application depends on your circumstances. For advice about your situation, consult a qualified solicitor or regulated professional. Unless stated otherwise, information relates to England and Wales.