Mental capacity and decision making

The Mental Capacity Act (MCA) protects a person's money, health and welfare, if they can't make all their own decisions because of a problem with how their brain functions.

This could be due to dementia, stroke or brain injury, or learning disability or mental health problem.

  • They may have the capacity to make everyday decisions, but not to make larger, more complex decisions.
  • They may have the capacity to make decisions one day but not the next.
  • Their capacity to make decisions might improve or get worse over time.

Find out how to check mental capacity on GOV.UK.

How does it affect family, friends and unpaid carers?

The Act protects a person's rights and is relevant to anyone who has a relative or friend who may lack capacity.  It covers major decisions about someone’s property and financial affairs, health and welfare and where they live.

  • It covers everyday decisions about personal care, when the person can’t make those decisions for themselves.
  • It clarifies the process for caring for people who may lack capacity.
  • It clarifies how decisions should be made for your relative or friend if they are unable to make those decisions for themselves.
  • It sets out when you should be consulted about decisions made on behalf of your relative or friend.
  • It sets out how your relative or friend is protected when others are making decisions on their behalf.

If a person lacks mental capacity, you can only make decisions about their health and finances if you have power of attorney - see representing someone who needs care and support.

Find out more about mental capacity on GOV.UK.

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