Synopsis
Support each person to decide wherever possible, assess capacity for the specific decision and time, apply best-interests safeguards when capacity is absent, and distinguish valid advance refusals from attorney authority and non-binding preferences.
- The Mental Capacity Act 2005 applies generally from age sixteen in England and Wales, while an ADRT or LPA requires adulthood at eighteen; Scotland and Northern Ireland have different legal frameworks.
- Presume capacity, take all practicable steps to support decision-making and do not equate an unwise decision with incapacity.
- Capacity is specific to the exact decision and time; a diagnosis or poor screening score does not confer global incapacity.
- The person lacks capacity only when an impairment or disturbance of mind or brain causes inability to understand, retain, use or weigh relevant information, or communicate the decision.
- Give salient information accessibly, including the nature, likely consequences, alternatives and consequences of deciding or not deciding.
- If a safe delay could restore capacity, treat delirium, pain or distress and assess at the person's best time with needed aids and support.
- A best-interests decision starts only after relevant incapacity is established and centres the person's wishes, feelings, beliefs, values and participation.
- Identify the lawful decision-maker, consult appropriate people, consider whether the purpose can be achieved as effectively in a less restrictive way, and record the overall best-interests decision.
- A valid and applicable advance decision refuses specified future treatment; refusing life-sustaining treatment requires writing, signature, witness and an explicit life-risk statement.
- A health-and-welfare LPA acts only when the donor lacks capacity for the decision and may decide life-sustaining treatment only if the donor expressly granted that authority.
- After [2026] UKSC 16, deprivation of liberty requires a multifactorial assessment of the concrete restrictions and the person's objection, wishes and feelings; the former acid test is no longer determinative.
Key red flags
Delirium, intoxication, hypoxia, hypoglycaemia, severe pain or communication failure can cause temporary apparent inability and needs immediate treatment and support.
Refusal of life-sustaining treatment requires urgent verification of current capacity or a valid, applicable advance decision rather than assumption from diagnosis.
A relative claiming power without a registered document, outside its scope or while the donor retains relevant capacity cannot decide merely through next-of-kin status.
Coercion, fear, dependency, financial pressure or rehearsed answers may undermine voluntariness without necessarily proving incapacity and needs safeguarding assessment.
Serious disagreement about best interests, attorney conduct or an advance decision may require safeguarding, mediation, legal advice or Court of Protection involvement.
Global cognitive scores, age, diagnosis, appearance, disability or an apparently unwise choice cannot establish lack of capacity.
Since [2026] UKSC 16, continuous supervision and inability to leave remain relevant but are not determinative: assess type, duration, effects and implementation of restrictions, objection, wishes and feelings multifactorially, and refer doubtful cases through current DoLS or court processes.
Investigation priorities
Specify the exact choice, salient information, urgency, alternatives and consequences before assessment.
Management branches
There is a concrete reason to doubt that a person can make a specific decision at the required time.
- Define the exact decision and salient information and take practicable steps to address communication, environment, distress and timing.
- Assess whether an impairment of mind or brain causes inability to understand, retain, use or weigh, or communicate the decision.
- Record evidence, causal reasoning, conclusion, emotional support, review timing and how the person can challenge or revisit the outcome.