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A healthcare practitioner comforts a lady during a mental capacity assessment illustrating fluctuating capacity

The Mental Capacity Act provides a framework to protect people who lack the capacity to make their own decisions and aims to maximise their ability to participate in any decision-making.

The Act sets out 5 guiding principles to protect people who lack capacity to make specific decisions. It also aims to maximise their ability to participate in decision-making.

  • A person must be assumed to possess capacity unless it is established that he/she does not s1 (2).
  • A person is not to be treated as unable to make a decision unless all practical steps have been taken to assist him/her have been taken s1 (3).
  • A person is not to be treated as unable to make a decision merely because it is unwise s1 (4).
  • Any act done or decision made under this act must be in the person’s best interests s1 (5).
  • Any act done or decision made must have regard for whether it can be made in a way that is the least restrictive to that person’s individual rights and freedoms s1 (6).

The Act, however, does not specifically address the issue of fluctuating capacity. Fluctuating capacity describes the situation where a person sometimes has the capacity to make their own decisions and sometimes does not. This can be due to a number of reasons but generally the cases suggest that these cases can be divided into broadly three groups.

  1. A temporary loss in mental functioning – mental health conditions that cause the person to become temporarily unable to make decisions. A change in mental health condition such as a manic episode brought on by a failure to take medication correctly or something relating to physical health like a urinary infection causing a period of confusion in an elderly person.
  2. Predictably fluctuating capacity – some conditions fluctuate predictably. A person with dementia may perform better in the morning and gradually lost their decision-making ability as the day progresses.
  3. Unpredictable fluctuations of capacity – in some conditions the fluctuations cannot be predicted, this group of clients may have severe brain injuries or brain disorders.

Whilst the Act does not provide any guidance on the approach for dealing with decision making for these individuals the accompanying Code of Practice does offers some guidance. It suggests that some people have fluctuating capacity as a result of “a problem or condition that gets worse occasionally and affects their ability to make their own decisions.” The examples given are manic depression or psychotic illness which have a temporary effect. The Code of Practice indicates that a person with fluctuating capacity may be supported to make a decision and suggests that it may be possible to put off the decision until the person has the capacity to make it.

Where the capacity loss is more permanent it could lead to the finding of a lack of capacity to make certain decisions.

In the case of Re E (Medical Treatment: Anorexia)1 a woman was deemed not to have the capacity to weigh up the factors relevant to making a decision to refuse medical treatment because her overriding compulsion to refuse food compromised her decision-making ability and prevented her from acting in her own best interests.

In the case of Royal Borough of Greenwich v CDM2 the court looked at the ability of a 64-year-old woman, with a personality disorder, to decline treatment for diabetes. The court expanded their analysis to look at micro and macro decisions. The decision in question was viewed as a macro or global decision – an interplay of many factors including health consequences, diet, insulin management, glucose blood testing and admission to hospital for treatment. Whilst the judgement acknowledged that she may have the capacity to make micro decisions in respect of some areas of her treatment sometimes at other times she may not. Overall, the expert opinion in the case suggested that the decision was a macro decision on a much broader footing which she did not have the capacity to make.

Re DY3 the case looked at the capacity of a young women to consent to sexual relations. She suffered from foetal alcohol syndrome and had a learning disability. She was in a settled relationship. Although she was said to have capacity to consent the local authority had raised a question of whether, when she became upset and distressed, she might not have the capacity to consent. In this case the court did not consider there was evidence to suggest that she was unable to give valid consent.

The assessment and management of fluctuating capacity remains a complex issue requiring detailed specialist opinion to confirm whether the client is able to effectively make their own decisions. The development of the case law in this area does assist in this analysis but it remains a balance between offering protection to the most vulnerable whilst ensuring that autonomy is retained where it is possible.

Written by Eve Carter of Hudgell Solicitors

Eve Carter is National Head of Court of Protection Services at Brain Injury Group member firm Hudgell Solicitors and specialises in Mental Capacity and Court of Protection issues.

Hudgell Solicitors serve clients nationwide and have offices in Hull, London and Manchester.

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1 Re E (Medical Treatment: Anorexia) (Rev1) [2012] EWCOP 1639 (15June 2012)
2 [2019] EWCOP 32 (20 February 2019)
3 [2021] EWCOP 28

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