Ethics England Wales

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5. Best interests

What does the Act mean by best interests?

All decisions taken on behalf of someone who lacks capacity must be taken in his or her best interests. The Act provides a checklist of common factors that must be taken into account when making a best interests judgement.

Subsequent case law has established that when assessing an individual’s best interests, decision makers must look at their welfare in the broadest sense. This must extend beyond medical factors to incorporate social and psychological dimensions of wellbeing. As part of the assessment process the courts have made it clear that the decision maker must also make a reasonable effort to put themselves in the place of the patient and ask what their attitude to the proposed treatment would be.


What should you take into account when assessing best interests?

Lacking capacity to make a decision should not exclude an individual from participating in the decision-making process as far as is possible. The decision maker must also take into account the likelihood that the person will regain capacity. A decision should be delayed if it can reasonably be left until he or she regains the capacity to make it.

Other relevant factors are likely to include:

  • the person’s past and present wishes and feelings, including any relevant written statement made when she or he had capacity – this would include general statements of wishes, beliefs or values where they would have an impact on the decision
  • other factors the person would have considered if able to do so – such as the effect of the decision on other people.

A crucial part of any best interests judgment will involve a discussion with those close to the individual, including family, friends or carers, where it is practical or appropriate to do so, bearing in mind the duty of confidentiality. (For more on information sharing, see card 16.) It should also include anyone previously nominated by the person as someone to be consulted.

Where an individual appointed to act under a Lasting Power of Attorney or a deputy appointed to make decisions by the Court of Protection has the authority to make the decision, they should be provided with as much information as is necessary for them to make the decision in question.

Further information about attorneys and court-appointed deputies is given later in the tool kit (see cards 11 and 12).


Are there any exceptions to the best interests principle?

There are two circumstances when the best interests principle will not apply. The first is where someone has previously made an advance decision to refuse medical treatment while they had capacity. Where the advance decision is valid and applicable, it should be respected, even if others think that the decision is not in his or her best interests (for more information on advance decisions, see card 9).

The second exception relates to the enrolment of incapacitated adults in certain forms of research. This is covered in more detail in card 10.


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