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Mental Capacity Act

The Mental Capacity Act protects people who cannot make decisions for themselves or lack the mental capacity to do so. This could be due to a mental health condition, a severe learning difficulty, a brain injury, a stroke or unconsciousness due to an anaesthetic or accident.

The Act's purpose is:

  • To allow adults to make as many decisions as they can for themselves. 
  • To enable adults to make advance decisions about whether they would like medical treatment in the future. 
  • To allow adults to appoint, before losing mental capacity, another person to make decisions about personal welfare or property on their behalf when they no longer have the capacity. 
  • To allow decisions about personal welfare or property and affairs to be made in the best interests of adults when they have not made any future plans and do not have the capacity to make a decision. 
  • To ensure an NHS body or local authority will appoint an independent mental capacity advocate (I.M.C.A.). The advocate will support someone who cannot make a decision about serious medical treatment, or about hospital, care home or residential accommodation, when there are no family or friends who can be consulted. 
  • To provide protection against legal liability for carers who have honestly and reasonably sought to act in the person's best interests. 
  • To provide clarity and safeguards around research in relation to those who lack capacity.

Under the Mental Capacity Act a person is presumed to make their own decisions 'unless all practical steps to help him (or her) to make a decision have been taken without success'.

Every person should be presumed to be able to make their own decisions. You can only take a decision for someone else if all practical steps to help them to make a decision have been taken without success. For example, someone might have the capacity to walk into a shop and buy a laptop but not to go into an estate agent and purchase a property.

Incapacity is not based on the ability to make a wise or sensible decision.

How to decide if a person lacks capacity to make decisions

If you are concerned about someone's health or wellbeing, you may need to know if they are capable of making their own decisions. Some people might need someone else to make decisions for them. You can find out here how someone's mental capacity can be assessed and how you can help them make decisions.

When people lack mental capacity

Every day people make decisions about lots of things in their lives from what to wear or what to eat to making decisions about medical treatment or financial matters. The ability to make decisions is called mental capacity. Some people have difficulties making some decisions all or some of the time. This could be because they have:

  • a temporary condition such as infection, illness, accident or the influence of alcohol or drugs;
  • a learning disability;
  • dementia;
  • a mental health problem;
  • a head injury;
  • a stroke.

The Mental Capacity Act 2005 sets out the legal rights for supporting and protecting vulnerable people who are not able to make their own decisions. It makes clear who can take decisions, in which situations, and how they should go about this. It also enables people to plan ahead for a time when they may lose capacity.

How mental capacity is assessed

An assessment of someone's mental capacity should be made at the time a particular decision needs to be made, usually by the person who needs the decision to be made. It is not usually necessary to undertake a formal assessment of capacity for what people eat or what people wear.

Any assessment starts with the assumption that the person has the capacity to make the decision in question.

An assessment must never be based simply on their age, their appearance, assumptions about their condition, or any aspect of their behaviour.

A solicitor can decide if someone is capable of making decisions or understanding things such as a will or a Lasting Power of Attorney. If in doubt, they can get an opinion from a doctor or another appropriate professional.

The Court of Protection has power to decide whether someone has mental capacity or not if there is a disagreement.

How to tell if someone can make a decision

There are several things to think about when assessing if a person can make a decision:

  • If the person understands what decision they need to make and why they need to make it
  • If the person understands what might happen if they do or do not make this decision
  • If the person can understand and weigh up the information relevant to this decision
  • If the person can communicate their decision (by talking, using sign language or any other means)
  • If the person can communicate with help from a professional (such as a speech and language therapist)
  • If there is a need for a more thorough assessment (perhaps by involving a doctor or other professional expert)

The person must not be treated as unable to make a decision just because they make decisions you don't agree with.

The Mental Capacity Act Code of Practice gives more detailed guidance on how to assess someone's ability to make decisions. 

Assessing capacity

If you are a professional making an assessment of someone's capacity you must complete the Capacity Assessment form.