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Resources for the Comprehensive Geriatric Assessment based
Proactive and Personalised Primary Care of the Elderly

Advance Care Planning :

Mental Capacity

Mental Capacity in the UK


Basic principles


Decisions and actions carried out under the Mental Capacity Act 2005 should be tested against the 5 key principles set out in Section 1.

The principles act as benchmarks for decision makers.

Although there is no duty placed on persons or bodies to apply the principles, a failure to do so could be cited in legal proceedings as evidence of unlawful conduct.



The five key statutory principles are:


1. A person must be assumed to have capacity unless it is established that he lacks capacity.

2. A person is not to be treated as unable to make a decision unless all practicable steps to help him to do so have been taken without success.

3. A person is not to be treated as unable to make a decision merely because he makes an unwise decision.

4. An act done, or decision made, under this Act for or on behalf of a person who lacks capacity must be done, or made, in his best interests.

5. Before the act is done, or the decision is made, regard must be had to whether the purpose for which it is needed can be as effectively achieved in a way that is less restrictive of the person’s rights and freedom of action.



What do the principles mean?


  • Key Principle 1


A person over the age of 16 is assumed to be mentally capable of making their own decisions.

This assumption can only be overridden if the person concerned is assessed as lacking the mental capacity to make a particular decision for him or herself at the relevant time.

The Mental Capacity Act sets out how this assessment should be conducted in Section 3.

Consequently, in legal proceedings, the burden of proof will fall on the person who asserts that capacity is lacking.


  • Key Principle 2


This provision, which is aimed at maximising the decision making capacity of individuals, is expanded upon in Section 3 (2) of the Mental Capacity Act.

The Explanatory Notes to the Mental Capacity Act suggest that "all practicable steps" could include "providing information relevant to the decision in a simple format, making sure the person is in an environment he is comfortable in or involving an expert in helping the person express his views" (para.18). The Parliamentary Joint Committee that reviewed the then draft Mental Capacity Bill said that such steps "might include using specific communication strategies, providing information in [a] more accessible form, or treating an underlying mental disorder to enable a person to regain capacity" (para.70).

Providing information over time may allow a person to assimilate information more completely, thereby maximising their actual understanding.

Resource constraints are clearly relevant to the practicability of the assistance that might be required.


  • Key Principle 3


This principle underpins the right to personal autonomy by preserving the right of a person to make an irrational, unusual or eccentric decision which, if viewed objectively, is not in that person’s best interests without the person being treated as being mentally incapable.

It does not prevent a capacity assessment being undertaken in respect of a person who makes an unwise decision, a series of unwise decisions, a decision that puts that person at risk, or who makes a decision which does not reflect that person’s values, beliefs or approach to risk taking.


  • Key Principle 4


The best interests principle, which must guide all actions done or decisions made on behalf of a person who lacks capacity is expanded upon is Section 4 of the Mental Capacity Act.

A clinician who follows a valid and applicable advance decision is not acting "for or on behalf of a person who lacks capacity", he or she is acting on the instructions of a capacitated individual.

The best interests principle does not therefore apply to such decisions and healthcare professionals must comply with a valid and applicable advance decision, even if they do not consider that it would be in the patient’s best interests to do so.


  • Key Principle 5


Someone making a decision on behalf of a mentally incapacitated person must consider whether it is possible to decide or act in a way that would interfere less with the person’s rights and freedom of action, or whether there is a need to act at all.

The intervention should be proportionate to the particular circumstances of the case.

On the basis that only "regard" must be had to this principle, an option which is not the least restrictive option can still be in the person’s best interests.

Advance Care Planning, CGA based Proactive Primary Care of the Elderly

This topic is part of the Advance Care Planning domain of the

Comprehensive Geriatric Assessment

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Advance Care Planning is one of 8 domains of the

Comprehensive Geriatric Assessment (CGA)

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