The Mental Capacity Act helps people aged 16 years and over who lack mental capacity, and those who take decisions on their behalf.
- aspects of common law relating to capacity and consent
- who can take decisions
- how they should do this
It affects anyone who has contact with people who lack mental capacity, for example, due to a learning disability, stroke, illness, mental disorder, the effects of drugs or alcohol or head injury; it also enables people to plan for a time when they may lose capacity in future.
For more information see our Mental Capacity leaflet.
Statutory principles of the Mental Capacity Act (MCA)
The MCA is underpinned by five statutory principles:
a presumption of capacity - every adult has the right to make their own decisions and must be assumed to have capacity to do so, unless it is established that they lack capacity
individuals being supported to make their own decisions - a person is not to be treated as unable to make a decision unless all practicable steps to help him or her to do so have been taken without success
unwise decisions - a person is not to be treated as unable to make a decision merely because he or she makes an unwise decision
best interests - an act or decision made under this act for or on behalf of a person who lacks capacity must be done, or made, in their best interests
least restrictive option - anything done for or on behalf of a person who lacks capacity should be the least restrictive of their rights and freedom of action
Assessing lack of capacity
The Act sets out a single clear test for deciding whether a person lacks capacity to make a particular decision. A lack of capacity cannot be established through a person's age, appearance, condition or aspect of their behaviour.