The short answer
- Capacity is assumed until it's testedEvery adult can make their own decisions unless it's shown, for that specific decision, that they can't. A diagnosis or an unwise choice is not proof on its own.
- It's assessed decision by decisionThere is no single label that marks someone in or out for good. Capacity can be there for one decision and not another, and it can change through the day.
- Someone else decides only in their best interestsDay to day that's usually whoever is with them. For money, property or a planned welfare decision, a Lasting Power of Attorney or a court-appointed deputy may hold that authority instead.
- DoLS covers care homes and hospitals, not a client's own homeIf you're ever worried a client's freedom is being restricted at home without proper authority, that isn't something to resolve informally.
This page draws on the Mental Capacity Act 2005, the Deprivation of Liberty Safeguards, and the Supreme Court judgment that changed how deprivation of liberty is assessed, checked against gov.uk, legislation.gov.uk and cqc.org.uk in September 2026.
What mental capacity means
What it means when someone can, or can't, decide
Mental capacity is the ability to make a particular decision at the time it needs to be made. It isn't a general verdict on a person, and having a condition that can affect thinking doesn't mean someone lacks capacity for everything, or for good.
Medication and its side effects
A stroke, a brain injury or a physical illness
Dementia, a learning disability or a mental health condition
Drugs, alcohol or being unconscious
If you support a client with dementia, capacity is likely to be where you see this most clearly: there for choosing what to wear in the morning, absent for a decision about their finances that same afternoon. Managing clients with dementia goes further into what that looks like day to day.
The five principles
The five rules the Mental Capacity Act sets for every decision
The Act applies whether the decision is about a client's finances, their medical treatment or what they have for breakfast, and it sets out five rules for approaching all of them.
Capacity is assumed
Help comes before a judgement
An unwise decision is still their decision
Best interests, once they can't decide
The least restrictive option
You are not expected to run a formal test on a client, and nothing in the Act asks you to. What it does ask, if you support someone day to day, is that you treat these five rules as your default rather than letting a diagnosis settle the question for you. Training for private carers covers professional judgement calls like this in more depth. The Act itself is set out in full on legislation.gov.uk, and gov.uk's collection of guidance is the plainest official summary.
How it's tested
The two-part test behind every capacity decision
There is no single form that marks someone as lacking capacity for good. Every assessment, formal or informal, works through the same two stages for the one decision in front of it.
- 1
Is there a reason it might be affected
Stage oneThe starting question is whether there's an impairment or disturbance in how the person's mind or brain is working right now, whether that's dementia, a brain injury, medication, intoxication or a mental health crisis. Without one of these, the question doesn't arise. - 2
Can they understand the information
Stage twoExplained in a way that suits them, with plainer words, pictures or extra time if that helps, not necessarily read word for word from a form. - 3
Can they retain it long enough to decide
Stage twoSome people can hold information for only a few minutes. That is still enough, as long as it lasts long enough to reach a decision. - 4
Can they weigh it up
Stage twoComparing the options and what each one means for them, not just repeating back what they were told. - 5
Can they communicate a choice
Stage twoAny way they can: speech, writing, sign, a gesture, or a single squeeze of a hand. If someone can't do this even with support, the assessment stops here.
Who decides, and under what authority
Who has the right to decide once someone can't
When someone lacks the capacity for a particular decision, somebody else has to make it for them, but not just anybody, and not without limits.
- 1
Start by assuming they can decide
Every adult is assumed able to make their own decisions, including ones you would not make yourself. A diagnosis, an unwise choice or a bad day is never proof on its own that someone cannot decide.
- 2
If it is in doubt, it gets tested for that decision
Capacity is assessed for one decision at a time, not as a general label, and it can change through the day. Whoever needs the answer asks whether the person can understand, retain, weigh up and communicate a choice about this specific thing.
- 3
They can decide: their choice stands
Even if it worries you, and even if their family disagrees with it. Capacity is about the ability to decide, not the wisdom of the decision.
- 4
They can't: someone decides in their best interests
For everyday things, that is usually whoever is with them, working from what the person would have wanted. For money, property or a specific welfare decision they planned for in advance, a Lasting Power of Attorney holder decides instead, if one was set up while they still had capacity.
- 5
No attorney and it is a significant decision: the Court of Protection
Selling a house, a major medical treatment, or a decision that restricts someone's freedom usually needs a deputy appointed by the court, or a one-off court order, rather than a decision taken informally by family or a carer.
A Lasting Power of Attorney only exists if the person set one up while they still had capacity, and it comes in two kinds: one for health and welfare, one for property and financial affairs. If a client's family mentions one, whoever holds it has the legal authority to decide within its scope ahead of anyone else, including you. Gov.uk explains how power of attorney works. Where there is no attorney and the decision is significant, such as selling a house or agreeing to a restriction on someone's freedom, the Court of Protection appoints a deputy or makes a one-off order, and that usually needs a solicitor. What a deputyship application costs sets out what that involves.
If you handle any money on a client's behalf, whoever holds a financial Lasting Power of Attorney or a deputyship is the person whose instruction you should be following, not whichever family member happens to answer the phone. Handling money for clients as a private carer covers what that looks like in practice.
Deprivation of liberty
What DoLS covers, and what changed in June 2026
Deprivation of Liberty Safeguards exist so that if someone who lacks capacity is cared for in a way that restricts their freedom, an independent check happens first, rather than the decision being made and left unchecked.
| Who authorises it | What happens | |
|---|---|---|
| A care home or hospital | The home or hospital applies to the local council | A trained assessor visits, checks the person lacks capacity for that decision and that the restriction is needed and proportionate, then grants or refuses the authorisation. |
| A client's own home or supported living | DoLS does not apply here | If the arrangements restrict someone's freedom and they haven't accepted them, it needs a Court of Protection order, not an informal decision by family or a carer. |
A care home or hospital
- Who authorises it
- The home or hospital applies to the local council
- What happens
- A trained assessor visits, checks the person lacks capacity for that decision and that the restriction is needed and proportionate, then grants or refuses the authorisation.
A client's own home or supported living
- Who authorises it
- DoLS does not apply here
- What happens
- If the arrangements restrict someone's freedom and they haven't accepted them, it needs a Court of Protection order, not an informal decision by family or a carer.
Source: gov.uk and Age UK's Deprivation of Liberty Safeguards factsheet, March 2026.
Until June 2026, the test for whether someone was being deprived of their liberty came from the 2014 Cheshire West ruling: if a person was under continuous supervision and control and not free to leave, that counted as a deprivation regardless of how content they seemed with their situation. On 2 June 2026 the Supreme Court overturned that test. It now asks for a broader look at the person's actual circumstances: the type and length of any restriction, whether they object to it, how ordinary the setting is, and whether they show, even without the ability to consent to it in law, that they understand and accept it. Gov.uk's guidance on the ruling sets out the full test. The practical effect in care homes and hospitals is fewer authorisations than before, because a resident who seems settled and unbothered by their arrangements may no longer count as deprived of their liberty at all.
What to do
What to do if a client's capacity or freedom worries you
You are not the person who rules on capacity or authorises a restriction, but you are often the person who notices first, because you see the same client regularly and know what's normal for them.
- 1
Write down what you noticed
Same dayWhat was different, when, and who else was there. A short, factual note protects the client and you if the moment is ever looked at again. - 2
Tell whoever holds the care plan
FirstUsually the family, or the person named as their contact. This isn't a decision to sit on. - 3
Tell the GP or district nurse
If it's medicalA sudden change in someone's ability to understand or communicate is worth a medical opinion, not just a note in a diary. - 4
Contact the council's adult safeguarding team
If someone is at riskFindable through gov.uk's council finder, for anything you believe crosses into abuse or an unlawful restriction on someone's freedom. Call 999 if someone is in immediate danger.
Reading a client's reactions carefully rather than assuming you already know the answer is the same skill behind reading consent to touch and behind a good risk assessment: notice, don't guess, and say something when you're unsure.
Questions
Questions carers ask about mental capacity
The Mental Capacity Act 2005 is the whole framework for any decision where someone's capacity is in doubt, from small daily choices to major medical or financial ones. Deprivation of Liberty Safeguards are a narrower safeguard inside it, and only apply when someone who lacks capacity is cared for in a care home or hospital in a way that restricts their freedom. Gov.uk's Mental Capacity Act collection covers both.
You can and often do, informally, for small everyday decisions, using the same two questions everyone uses: is there a reason it might be affected, and can they understand, retain, weigh up and communicate this particular choice. For anything contested, or with real consequences, involve the client's GP or social worker rather than deciding it alone.
No. DoLS only covers care homes and hospitals. If a client cared for at home is having their freedom restricted and hasn't agreed to it, that needs a Court of Protection order, not an informal decision by their family or by you.
The Court overturned the 2014 "acid test", which said continuous supervision plus not being free to leave meant a deprivation of liberty regardless of how the person felt about their situation. The test now looks at the person's whole circumstances, including whether they object and whether they seem to accept the arrangement, even if they lack the capacity to consent to it in law. Gov.uk's guidance sets out the full test.
It's a legal document letting someone choose, while they still have capacity, who decides for them later, either over health and welfare or over property and money. If a client's family mentions one, whoever holds it has the authority to decide within its scope, ahead of anyone else including you. Gov.uk explains how they work.
A best interests decision should take into account what the person would have wanted and the views of people who know them, but where there's a valid Lasting Power of Attorney or a court-appointed deputy, their decision stands for the areas it covers. If something feels wrong, raise it with the GP or the council's adult social care team rather than acting on your own view of what's best.
Contact their local council's adult safeguarding team, found through gov.uk, or the police on 999 if someone is in immediate danger. Tell the family what you've seen and why you're concerned too, unless doing so isn't safe.