Mental capacity

Mental capacity

Mental capacity

‘Mental capacity’ means being able to make your own decisions

Someone lacking capacity – because of an illness or disability such as a mental health problem, dementia or a learning disability – cannot do one or more of the following four things:

  • Understand information given to them about a particular decision
  • Retain that information long enough to be able to make the decision
  • Weigh up the information available to make the decision
  • Communicate their decision.

We all make decisions, big and small, every day of our lives and most of us are able to make these decisions for ourselves, although we may seek information, advice or support for the more serious or complex ones. For large numbers of people their capacity to make certain decisions about their life is affected either on a temporary or on a permanent basis.

  • A person with a learning disability may lack the capacity to make major decisions, but this does not necessarily mean that they cannot decide what to eat, wear and do each day.
  • A person with mental health problems may be unable to make decisions when they are unwell, but able to make them when they are well.
  • A person with dementia is likely to lose the ability to make decisions as the dementia gets more severe.

What causes a lack of mental capacity?

A lack of mental capacity could be due to:

  • A stroke or brain injury
  • A mental health problem
  • Dementia
  • A learning disability
  • Confusion, drowsiness or unconsciousness because of an illness or the treatment for it
  • Substance or alcohol misuse.

The Mental Capacity Act 2005

Many people provide health treatment or social care support to people who may have difficulties making some or all decisions about their lives. Details of the Assisted Decicion Making Bill 2013 is here: http://humanrights.ie/mental-health-law-and-disability-law/assisted-decision-making-capacity-bill-2013-finally-published/

The Act can apply to all sorts of decision such as:

  • major decisions such as decisions about personal finance, social care or medical treatment
  • everyday decisions such as decisions about what to wear or eat

The law works on the principle that everyone is assumed to have capacity to make decisions for themselves if they are given enough information, support and time. It protects their right to make their own decisions and to be involved in any decisions that affect them. A person’s capacity must be judged according to the specific decision that need to be made, and not solely because of their illness, disability, age, appearance or behaviour.

An important principle in the law is that just because someone is making what seems to be an unwise decision (even if they have an illness or disability) this does not necessarily mean they lack capacity. There are legal safeguards that must be followed when making a decision on behalf of some who lacks the capacity to make the decision – it must be done in their ‘best interest’.

Plan to protect your mental health and wellbeing:


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