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Mental Capacity Act (MCA) practice guidance

Part 2 The Principles

Mental Capacity Act section 1; Code of Practice Chapter 2

  1. A person must be assumed to have capacity unless it is established that s/he lacks capacity.
  2. A person is not to be treated as unable to make a decision unless all practicable steps to help him/her to do so have been taken without success.
  3. A person is not to be treated as unable to make a decision merely because s/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/her best interest.
  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?

The five Principles of the Mental Capacity Act (MCA) are part of the legislation, so it is a legal obligation to respect these Principles whenever MCA is used.

Principle 1: The Principles assume capacity. Unless you have evidence that someone lacks capacity, you must assume that they can make their own decision. If there are doubts about someone’s capacity this must be assessed rigorously, and you need to find the evidence about their capacity. (Part 6: How to assess capacity)

Principle 2: You need to do everything you realistically can to enable someone to make their own decision. For instance, make sure they are comfortable; explain the information in as many ways as possible, use different communication methods and visit as often as possible. (Part 6: How to assess capacity)

Principle 3: Everyone makes decisions which might seem unwise to other people. An unwise decision should not be taken as an indication of someone’s capacity. For instance, someone may refuse treatment or care which they clearly need. If they have capacity to make this decision this is their right and they can refuse up to the point of death: if they lack capacity others will need to make a best interests decision for them. The person’s capacity for the decision must be carefully assessed and their refusal must not be used as evidence of a lack of capacity. (Part 8: Best interests decisions)

Principle 4: Everything done under MCA must be done in the interests of the individual. This means that a best interests decision made under MCA must be in that person’s interests and not in the interests of their family, of other people on the ward or the general public. (Part 8: Best interests decisions)

Principle 5: Anything done under MCA must be the minimum action necessary, must allow the person as much freedom of choice as possible and must follow their wishes as closely as possible. (Part 8: Best interests decisions)