How to Challenge a Capacity Decision

Created: 11 July 2026

Learn how to challenge a capacity decision lawfully and clearly, with practical steps, evidence tips and options for families and professionals.

When a professional says a person lacks capacity, the effect can be immediate and far-reaching. It can influence where someone lives, how their care is arranged, whether they can manage finances, or how key medical decisions are made. If you believe that finding is wrong, knowing how to challenge a capacity decision can make a real difference - but the challenge needs to be grounded in evidence, law and proper process.

Under the Mental Capacity Act 2005, capacity is both decision-specific and time-specific. A person may be able to make some decisions but not others. They may also have fluctuating capacity, particularly where there is dementia, acquired brain injury, mental ill health, learning disability, substance misuse or acute medical illness. That means a capacity decision should never be treated as a broad label. It should relate to the particular decision in question and the person’s ability at the time the assessment was carried out.

When a capacity decision may be open to challenge

Not every disagreement means the assessment is flawed. Sometimes the outcome is upsetting but legally sound. Equally, there are situations where concern is justified.

A decision may need to be challenged if the assessor did not properly identify the exact decision being assessed, relied on diagnosis alone, failed to support the person to participate, or did not apply the two-stage test required by the Act. Problems also arise when an assessment is too brief, poorly recorded, based on outdated information, or carried out at a time when the person was unwell, distressed or unable to engage.

Another common issue is confusion between an unwise decision and a lack of capacity. The law is clear that a person is not to be treated as unable to make a decision merely because others think the decision is unwise. If the person understands, retains, uses or weighs the relevant information, and can communicate their decision, the fact that professionals or family members disagree with the choice does not itself prove incapacity.

Start with the assessment itself

If you want to challenge a capacity decision, ask for the assessment records as early as possible. You will usually need to see who completed the assessment, what qualifications or role they had, what information they considered, when the assessment took place, and how they recorded the person’s responses.

Look carefully at whether the report explains the functional element and the diagnostic element. The first question is whether the person can make the decision. The second is whether there is an impairment of, or disturbance in, the functioning of the mind or brain which prevents the person from making the decision. A lawful assessment must address both.

It should also show how the assessor considered the four functional areas: understanding relevant information, retaining it long enough to decide, using or weighing that information as part of the process, and communicating the decision. If the report simply states conclusions without showing how those conclusions were reached, that can weaken its reliability.

How to challenge a capacity decision in practice

The right route depends on the setting and the seriousness of the consequences. In some cases, a prompt and well-reasoned request for review will resolve the issue. In others, the matter may need to go before the Court of Protection.

A useful first step is to raise your concerns in writing with the organisation that made or relied upon the decision. Keep the tone factual and focused. Set out the decision being challenged, the date of the assessment, why you believe the assessment was flawed, and what you want to happen next. That may be a reassessment, a specialist second opinion, or a pause on major decisions until the position is clarified.

Where possible, refer to specific concerns rather than general dissatisfaction. For example, you might say the person was assessed during a period of delirium, that no communication support was provided despite known needs, or that the report does not show how the person was helped to understand the options. Precision matters, particularly where legal professionals, local authorities, health bodies or deputies are involved.

The value of independent evidence

In more complex cases, independent professional evidence is often the most effective way to challenge the original finding. An independent mental capacity assessment can provide a fresh, evidence-based opinion that addresses the statutory test properly and sets out the reasoning in a clear format.

This is particularly helpful where there are competing views between family members and professionals, concerns about undue influence, or major decisions about residence, care, contact, finances, property or medical treatment. Independent evidence can also assist where the original assessment was undertaken by someone without sufficient expertise in the person’s presentation or communication needs.

A strong independent report will usually identify the specific decision under review, record the support offered to maximise participation, explain the person’s presentation on the day, and give a reasoned opinion linked to the legal criteria. That level of detail is often what decision-makers, solicitors and the court need.

When the Court of Protection may be needed

Some disputes cannot be resolved informally. If the disagreement is serious, ongoing, or has significant consequences for the person’s welfare or property and affairs, the Court of Protection may need to determine capacity.

This is more likely where there is a dispute about residence, care arrangements, contact restrictions, management of assets, or the validity of decisions being taken on the person’s behalf. The court can consider evidence from different professionals and decide whether the person has capacity in relation to the issue before it.

If proceedings are already underway, the challenge should be coordinated carefully with the person’s solicitor, litigation friend, deputy or other legal representative. Timing, evidence and the framing of the issue are all important. A broad complaint that the assessment felt unfair is unlikely to carry much weight without supporting material.

Key points for families and professionals

Families often feel that a loved one was not given a fair chance. Professionals, on the other hand, may be concerned about risk and the need to act quickly. Both perspectives can be valid. The law tries to balance protection with autonomy, which is why the quality of the assessment process matters so much.

If you are a family member, it helps to keep records of what the person can do, how they usually communicate, and whether their presentation varies by time of day, medication, fatigue or stress. Practical examples can be valuable, especially where capacity fluctuates.

If you are a solicitor, deputy or care professional, make sure the challenge stays tied to the legal test. Evidence is strongest when it addresses the specific decision, the support that should have been offered, and the person’s functioning at the relevant time. Broad statements that someone is generally capable, or generally incapable, are rarely enough on their own.

Common pitfalls when challenging a decision

One difficulty is focusing only on outcome. A person may strongly wish to return home, refuse care, or make a financial decision others see as risky. The issue is not whether that choice appears sensible. The issue is whether the person can make it in law.

Another pitfall is assuming that a new diagnosis automatically changes the answer. Diagnosis may be relevant, but it does not settle the question. Equally, a person with a longstanding cognitive impairment may still have capacity for certain decisions if the information is presented properly and they are given the right support.

There is also a practical point about delay. Capacity can change, records can become harder to obtain, and significant decisions may be implemented quickly. Early action usually gives the best chance of a meaningful review.

Why careful reporting matters

A capacity dispute often turns on the quality of the written evidence. Decision-makers need more than a conclusion. They need to see the basis for it. That is why clear, compliant and decision-specific reporting is so important in these cases.

An effective report should be legally informed without losing sight of the person behind the case. It should reflect how the person was engaged, what barriers were considered, and why the opinion reached is justified. In sensitive matters, that balance of legal accuracy and humane practice is not optional - it is essential.

For families and professionals dealing with contested capacity, independent social work evidence can be especially useful where the case sits across care, welfare and legal decision-making. Services such as Simply Social Work are often instructed in exactly these circumstances, where the quality of the assessment and report may affect court proceedings, professional decision-making or future care planning.

If you are considering a challenge, the most helpful next step is often the simplest one: identify the exact decision, obtain the assessment, and test whether the legal process was followed properly. A careful challenge, backed by sound evidence, gives the person’s rights the serious attention they deserve.