Few conversations are as difficult as the one where a family starts to wonder whether a parent, partner or relative can still manage their own affairs. It might begin with a missed bill, a confused phone call, or a solicitor asking a question nobody quite knows how to answer. Whatever the trigger, the subject of mental capacity tends to arrive at a moment that already feels stressful enough.
A mental capacity assessment is often mentioned at this point, but many families, and even some professionals who do not work with it daily, are unsure what one actually involves, who can carry one out, or when it is genuinely needed. This guide sets out to answer those questions clearly, so that if you find yourself facing this situation, you know what to expect and what to ask for.
Understanding Mental Capacity In Law
Mental capacity is not a single, fixed state that a person either has or does not have. In law, capacity is specific to both the decision being made and the moment it is made in. Someone may be entirely able to decide what to eat for lunch, choose what to wear, or express a preference about a visit from a relative, while genuinely struggling to understand the implications of a large financial transaction or a change to their will.
This distinction matters enormously in practice. A diagnosis such as dementia, a brain injury, or a mental health condition does not automatically mean someone lacks capacity for every decision, and it is a mistake to assume otherwise. The starting position in any assessment, set out clearly in the Mental Capacity Act 2005, is that a person is presumed to have capacity unless it can be shown, on the balance of probabilities, that they do not. That presumption exists precisely to protect people from having decisions taken away from them too readily.
Capacity can also fluctuate. Someone might have good days and difficult days, or their ability to engage with a particular decision might change depending on their health, medication, or the time of day. A proper assessment takes this into account rather than treating one difficult conversation as the final word.
When Families And Professionals Turn To An Assessment
There are a handful of situations where the question of capacity comes up again and again. A common one is when a Lasting Power of Attorney needs to be enacted, and the attorney or the family wants confirmation that the person can, or cannot, still make the relevant decisions themselves. Another is when a solicitor is asked to prepare or update a will and wants to be satisfied, before the document is signed, that the person has testamentary capacity, meaning they understand the nature of the decision, the extent of what they own, and who might reasonably expect to benefit.
Assessments are also requested when a family disagrees about how to support a relative. One sibling might feel their parent is coping perfectly well, while another is worried about safety or financial vulnerability. In cases like this, an independent, professionally written assessment can settle a dispute far more effectively than another difficult family conversation. Care providers, including care homes and supported living services, will sometimes commission an assessment before making a best interests decision on someone’s behalf, particularly where that decision is significant, such as a change of residence or a restriction on someone’s usual freedom of movement.
What all of these situations share is that the outcome matters. A will that is later challenged, a Power of Attorney that is disputed, or a care decision that a family does not trust, can all cause lasting harm to relationships and, in some cases, lead to expensive legal proceedings. Getting a proper assessment at the right time is usually far less costly, in every sense, than dealing with the consequences of not having one.
What A Proper Assessment Involves
A genuine mental capacity assessment is considerably more thorough than a short conversation or a brief note from a GP confirming that someone seems fine. It should involve a structured discussion with the person concerned, carried out in a setting where they are comfortable, and focused specifically on the decision in question rather than a general impression of how they present.
The assessor will typically explain the decision to the person in plain terms, check their understanding of the relevant information, ask how they weigh up the options available to them, and see whether they can communicate a decision, in whatever way is natural for them. Throughout, the assessor is testing the specific decision at hand, not simply forming an overall view of the person’s mental state.
Just as importantly, the outcome should be recorded in a written report that explains the reasoning behind the conclusion, not only the conclusion itself. This matters because these reports are often relied upon later by solicitors, courts, or local authorities, sometimes years after the assessment took place. A report that simply states has capacity or lacks capacity without explaining why is of limited use if it is ever challenged. A common mistake families make is assuming that any letter from a doctor confirming a diagnosis will serve the same purpose. A diagnosis is medical information. A capacity assessment is a specific, decision focused judgement, and the two are not interchangeable.
Common Misunderstandings About Capacity
A number of misconceptions come up regularly, and it is worth addressing them directly. The first is the belief that a diagnosis of dementia or a similar condition automatically removes someone’s capacity across the board. As explained earlier, this is not how the law works. Capacity is assessed decision by decision.
The second misunderstanding is that family members can simply decide, among themselves, that a relative lacks capacity and begin making decisions on their behalf. Without a valid Lasting Power of Attorney or a court appointed deputyship, family members do not automatically have that legal authority, however good their intentions.
A third common assumption is that an assessment is only relevant once a crisis has already happened, such as after a fall or a serious financial mistake. In reality, families and professionals are often better served by seeking an assessment proactively, particularly around events like signing a will, granting a Power of Attorney, or making a significant financial decision, precisely so that capacity is documented at the time the decision is made rather than questioned retrospectively.
Bringing It All Together
If there is one thing to take away from all of this, it is that capacity is specific, not general, and that a proper assessment protects everyone involved, including the person at the centre of it. Families facing this situation should prioritise getting an assessment from someone independent of the outcome, rather than relying on an informal view, however well meaning. Acting early, particularly around wills, Powers of Attorney, and significant financial or care decisions, tends to prevent far more difficult disputes later on.
Frequently Asked Questions
How long does a mental capacity assessment usually take?
Most assessments involve at least one structured meeting with the person concerned, though this can be split across more than one session if their concentration or health means that is more appropriate. Once the meeting has taken place, preparing a thorough written report typically takes a further period of time, since the reasoning needs to be set out clearly enough to stand up to scrutiny later, rather than being rushed out the same day.
What happens if the assessment finds that someone lacks capacity for a specific decision?
The assessment will normally recommend that any decision in that specific area be made in the person’s best interests, following the process set out in the Mental Capacity Act. This usually involves consulting those close to the person, considering their past wishes and feelings where known, and choosing the option that least restricts their rights while keeping them safe. It does not mean the person loses all decision making authority in every area of their life.
Can a mental capacity assessment be challenged or questioned later?
Yes. This is exactly why a properly reasoned, independent written report matters so much. If an assessment is ever queried by another family member, a solicitor, or a court, a report that explains the process followed and the reasoning behind the conclusion is far more likely to be accepted than a brief note with no supporting detail.
Can a GP carry out a mental capacity assessment instead of an independent social worker?
A GP can comment on a person’s medical condition and may be asked for an opinion in some circumstances, but a dedicated capacity assessment, particularly one that needs to stand up in a legal or financial context, is a specific skill that goes beyond a standard medical consultation. Many solicitors and families prefer an assessment from a professional whose main focus is capacity work, precisely because of the depth and independence it provides.
What should I bring or prepare before an assessment takes place?
It helps to have a clear idea of the specific decision the assessment relates to, along with any relevant documents, such as a draft will, a Power of Attorney form, or details of the financial or care decision in question. It is also useful to think about a time and setting where the person is likely to be most comfortable and alert, since this can genuinely affect how well the conversation goes.
Getting Independent, Professional Support
Every family’s situation is different, and the right next step depends on exactly what decision is in question and who is involved. What tends to help most is speaking to someone independent early, before a disagreement or a rushed decision makes things more complicated than they need to be.
I am Susan Dyball, an independent social worker registered with Social Work England, and I carry out mental capacity assessments, second opinions and related reports for families, solicitors and care providers across Teesside and the wider North East. If you are facing a decision where capacity is in question, get in touch for a straightforward conversation about your situation and what an assessment would involve.