When is a decision merely unwise?

Steve Treviss
7 February 2019

This article looks at the distinction that the Mental Capacity Act 2005 makes between lacking mental capacity to make a decision and merely unwise decisions, explains the test used to make that distinction, and emphasises the importance of the provision.

The Concept

A founding principle of the MCA is that a person must not be ‘treated as unable to make a decision merely because he makes an unwise decision’. This allows a distinction to be made between decisions thought to be simply unusual or eccentric, on the one hand, and ones which are due to an inability, due to mental impairment, to carry out the mental process needed to make that decision, on the other. The distinction is important because in preventing others from imposing their own values, beliefs, preferences and attitudes on the person whose mental capacity is being assessed, the individual’s personal autonomy is preserved. For example, if a doctor decides that a certain form of treatment is in your best interests, you should not be deemed to lack the mental capacity to make a decision about whether or not to have the treatment, purely on the basis that you are refusing expert advice.

When a decision is merely unwise and the functional test

This raises the important question of when a decision stops being merely unwise and becomes about the ability to make that decision.

The starting point is that a person is always presumed to have mental capacity to make any given decision. If there is reason to believe that someone might lack the capacity to make a decision, then they have to be assessed. Mental capacity is determined using a two-stage test. Firstly, the person has to have ‘an impairment of the mind or brain’. Secondly, they must be unable to carry out the process of making the decision as a result of that impairment. Both elements of the test must be met. If one element is not met, the person should be deemed to have capacity to make the decision.

However, it is the second part of the two-stage test, known as the ‘functional test’, which allows the distinction to be drawn between people making unwise, eccentric or even risky decisions that do not result in a lack of capacity, and actually being unable to make a decision. This is because the functional test shifts the focus away from a judgement by a capacity assessor on the outcome of the decision and what they think is a sensible conclusion to arrive at, and instead focuses on a set of abilities needed to arrive at that decision.

The set of abilities needed to make a decision on a specific issue involve being able to understand the information relevant to the decision, to retain, and use or weigh that information as part of the process of making the decision that you are able then to communicate. If an individual is able to do this as part of the decision-making process, they should be deemed capable of making the decision, whether the outcome is thought to be unwise or not. It is therefore the process by which a person arrives at a decision, and not the decision itself, that determines whether a person is capable of making it.

So, to return to our initial example of medical treatment, a consultant may recommend an operation that has life-saving potential. However, the patient may decide that, against the professional advice, he does want to go through with this. Broadly speaking, provided he understands the information that he has been given, can retain it sufficiently to consider it in a reasoned way, and can communicate that decision to the consultant, there should be no question that he has the capacity to make a decision to refuse the operation.

Conclusion

The net effect of this provision is therefore to provide a threshold, beyond which, a person’s ability to make a decision cannot be questioned. More importantly, it acts to prevent any assessment of capacity to make a particular decision being based on the subjective beliefs and values of the assessor, or indeed those that might have been instrumental in raising the question of capacity that led to that assessment, meaning that (to the extent that this is possible) an objective approach that preserves and protects personal autonomy, is taken.

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