Skip to main content

Adults lacking capacity

The Mental Capacity Act (MCA) 2005 provides a statutory framework for people who may not be able to make their own decisions, for example because of learning difficulties, brain injury or mental health problems. It sets out who can take decisions, in which situations, and how they should go about this. The Act applies to England and Wales only.

Where a prospective participant is approached to take part in the research and lacks the capacity to give informed consent to participate a ‘legal representative’ may give assent on his / her behalf. The person unable to give consent should still receive information according to their capacity to understand, setting out the risks and benefits of participating in the research.

In the case of an adult this could be a person designated by the adult, a relative or an independent person nominated by, for example, the hospital at which the research is being undertaken. If the adult has appointed a representative who is available, then this person must be used to give assent. A relative can only be used if the person has not appointed a representative or if the representative is not available. An independent person should only be used if both the adult’s representative and a relative are not available.

Consequently, an independent person must only be used to give assent on an adult’s behalf where the research cannot be conducted if there is delay (i.e. research in an clinical emergency situation), where the person whose representative or relative is not available is indispensable for the research, and where the research is of sufficient importance to justify the giving of assent on behalf of the adult concerned. In such cases the independent person, responsible for the care of the adult, cannot be used if s/he is involved in the research or has any direct interest in it.

At the heart of the MCA in terms of concepts and values are the five ‘statutory principles’. Consider the five principles as the benchmark – use them to underpin all acts done and decisions taken in relation to those who lack capacity. In doing so, you will better empower and protect individuals who lack capacity. It is useful to consider the principles chronologically: principles 1 to 3 will support the process before or at the point of determining whether someone lacks capacity. Once you have decided that capacity is lacking, use principles 4 and 5 to support the decision-making process.

The five key underpinning principles (Section 1, MCA)

Principle 1: A presumption of capacity

Every adult has the right to make his or her own decisions and must be assumed to have capacity to do so unless it is proved otherwise. This means that you cannot assume that someone cannot make a decision for themselves just because they have a particular medical condition or disability.

Principle 2: Individuals being supported to make their own decisions

A person must be given all practicable help before anyone treats them as not being able to make their own decisions. This means you should make every effort to encourage and support people to make the decision for themselves. If lack of capacity is established, it is still important that you involve the person as far as possible in making decisions.

Principle 3: Unwise decisions

People have the right to make what others might regard as an unwise or eccentric decision. Everyone has their own values, beliefs and preferences which may not be the same as those of other people. You cannot treat them as lacking capacity for that reason.

Principle 4: Best interests

If a person has been assessed as lacking capacity then any action taken, or any decision made for, or on behalf of that person, must be made in his or her best interests.

Principle 5: Less restrictive option

Someone making a decision or acting on behalf of a person who lacks capacity must consider whether it is possible to decide or act in a way that would interfere less with the person’s rights and freedoms of action, or whether there is a need to decide or act at all. In essence, any intervention should be proportional to the particular circumstances of the case.

For further guidance on the above area please see the MRC’s website.