Why Capacity Is Always Decision-Specific (And Why That Matters)

As a mental capacity assessor, I am often asked why multiple assessments are needed for the same individual. From the outside, it can seem repetitive, even unnecessary. However, one of the most fundamental principles of capacity is that it is decision-specific. This means that a person may have the capacity to make some decisions, but not others.

For example, an individual may be able to decide what to wear, what to eat, or where to live. At the same time, they may lack the capacity to make more complex decisions, such as investing money, purchasing property, or taking out a loan. These are not contradictions, they reflect the reality that different decisions require different levels of understanding and reasoning.

The Legal Framework Behind Capacity

All capacity assessments are grounded in key legal principles. These include:

The presumption of capacity, meaning every adult is assumed to have capacity unless proven otherwise.

The requirement to take all practicable steps to support an individual in making their own decision before concluding they lack capacity.

The recognition that individuals are entitled to make unwise decisions. A poor decision does not, in itself, indicate a lack of capacity.

The requirement that any inability to make a decision must be caused by an impairment or disturbance in the functioning of the mind or brain. This impairment may be evidenced through a formal diagnosis, clinical findings or other observable indicators of cognitive disturbance.

The Functional Test: The Core of Every Assessment

Most capacity assessments are structured around the functional test set out in the Mental Capacity Act 2005. This requires us to consider whether a person can:

Understand the information relevant to the decision.

Retain that information long enough to make the decision.

Use or weigh that information as part of the decision-making process.

Communicate their decision by any means.

While these criteria remain constant, the information relevant to the decision changes every time.

What Counts as “Relevant Information”?

Relevant information is not generic, it is tailored to the specific decision being assessed. In litigation capacity assessments, for example, relevant information may include:

• How the case is being funded.

• The risks of losing, including potential costs.

• The nature of the claim.

• The decisions that may arise throughout proceedings.

These points are often drawn from formal guidance, such as a certificate of capacity to conduct proceedings.

However, how this information is explored depends entirely on the individual. Questions might include:

• “What are you asking the court to decide for you?”

• “What does no win, no fee mean?”

• “What could happen if the case is unsuccessful?”

These are not fixed scripts and every assessment is person-specific, requiring the assessor to adapt language, pace and questioning in real time to ensure the individual is supported to demonstrate their ability.

Why One Assessment Isn’t Enough

I was once asked to complete a testamentary capacity assessment, to determine whether an individual had the capacity to make a will. Testamentary capacity is governed not by the Mental Capacity Act, but by the long-standing case of Banks v Goodfellow.

This requires that the individual understands:

The nature of making a will.

The effects of making a will.

The extent of their estate.

The claims of potential beneficiaries.

Any moral obligations they may have.

Following the assessment, I was satisfied that the individual had the capacity to proceed and the will was signed. However, immediately afterwards, I was asked to sign additional documents confirming that the same individual had capacity to:

1. Add a personal assistant as a cardholder on their bank account.

2. Appoint a Lasting Power of Attorney for property and finances.

This is where the principle of decision-specific capacity becomes critical.

Why Capacity Does Not “Carry Over”

The relevant information required to appoint a Lasting Power of Attorney is significantly more complex than that required to make a will. To appoint an LPA, an individual must typically understand:

• The legal effect of the LPA.

• Who the attorneys are.

• The scope of their powers and any restrictions.

• When those powers can be used.

• The range of assets they may control.

• The ability to revoke the LPA while capacitous.

• The risks and benefits of creating, or not creating, the LPA.

When compared to testamentary capacity, there is minimal overlap. Although the individual had the capacity to make a will, this did not automatically mean they had the capacity to grant a Lasting Power of Attorney. These are distinct legal decisions, requiring separate assessments.

Why This Can Feel Frustrating

For individuals and families, this process can understandably feel repetitive. It may involve multiple assessments, additional time and increased cost. However, this approach exists for an important reason.

A thorough, decision-specific assessment protects the individual at the centre of the decision, their family and support network and the professionals involved. Most importantly, it ensures that decisions are made lawfully, safely and in the person’s best interests where required.

When Things Go Wrong

The importance of this approach is highlighted in case law. In The Public Guardian v RI & Others (2022), an individual with a lifelong learning disability and chronic schizophrenia had executed an LPA. However, following safeguarding concerns, retrospective review concluded that he was unlikely to have had capacity at the time. As a result, the LPA was declared invalid and cancelled. Had a proper capacity assessment been undertaken at the time, concerns may have been identified earlier and alternative safeguards could have been put in place to protect the individual.

This is also why capacity evidence can be so important in Court of Protection matters, particularly where there are disputes, safeguarding concerns, deputyship issues or questions about whether a previous legal document should be relied upon.

Final Thoughts

Capacity assessments are not about restricting autonomy, they are about protecting it. By recognising that capacity is decision-specific, we ensure that individuals are supported to make their own decisions wherever possible, while also safeguarding them where they cannot.

It may take more time and may require more than one assessment, but ultimately it is a process designed to get the right decision, for the right person, at the right time.

Genevieve Walls