The ‘Mental Capacity Act’ is an important law for people with a learning disability.

It helps make sure that people who may lack capacity make their own decisions and get the support they need to make those decisions.

Where they are not able to make their own decision, it says a decision must be made that is in their ‘best interests’.

The Mental Capacity Act

The Mental Capacity Act 2005 is a law that protects vulnerable people over the age of 16 around decision-making. It says that:

Every adult, whatever their disability, has the right to make their own decisions wherever possible. 

People should always support a person to make their own decisions if they can. This might mean giving them information in a format that they can understand (for example this might be easy read information for a person with a learning disability) or explaining something in a different way.

But if a decision is too big or complicated for a person to make, even with appropriate information and support, then people supporting them must make a ‘best interests’ decision for them.

The 5 main principles of the Mental Capacity Act

  1. Everyone is believed to have capacity to make decisions unless it can be proved that they do not.
  2. A person should be supported to make their own decisions using all practicable steps before it is decided that they are unable to do so.
  3. A person should not be considered unable to make a decision simply because their decision is considered unwise or eccentric by others. (If capacity is in doubt at this stage and the person has a disorder of the mind, no matter how caused, use the four point capacity test below).
  4. Any decision made on behalf of someone who lacks capacity must be made in their best interests.
  5. Any best interests decision must take account of all the circumstances and take the least restrictive course of action available to maintain the person’s basic rights and freedom.

Supporting someone to make a decision

Before deciding that someone lacks the capacity to make a decision, all practical and appropriate steps must be taken to help them make the decision themselves. 

The Mental Capacity Act Code of Practice is important guidance on how the law should be applied in particular situations. It includes a summary about how to help someone make a decision in four main principles:

1. Provide relevant information

  • Does the person have all the relevant information they need to make a particular decision?
  • If they have a choice, have they been given information on all the alternatives?

2. Communicate in an appropriate way

  • Could information be explained or presented in a way that is easier for the person to understand (for example, by using simple language or visual aids)?
  • Have different methods of communication been explored if required, including non-verbal communication?
  • Could anyone else help with communication (for example, a family member, support worker, interpreter, speech and language therapist or advocate)?

3. Make the person feel at ease

  • Are there particular times of day when the person’s understanding is better?
  • Are there particular locations where they may feel more at ease?
  • Could the decision be put off to see whether the person can make the decision at a later time when circumstances are right for them?

4. Support the person

  • Can anyone else help or support the person to make choices or express a view?

Making a best interests decision

If, after all steps have been taken to support someone to make their own decision, the person is assessed as lacking capacity to make that particular decision, then a ‘best interests’ decision must be made.

The person who makes the ‘best interests’ decision is called the ‘decision maker’. Who the decision maker is will depend on the situation and the type of decision.

For example:

  • For most day-to-day decisions the ‘decision maker’ is likely to be the person who is supporting the person.
  • Where it is a decision about healthcare it will be the relevant health professional.

Whoever is the decision maker, it is important they talk with others involved with the person, and involve the person themselves as much as possible, to get a good understanding and therefore make the best decision they can.

Best interests checklist

The Mental Capacity Act sets out a best interests checklist, which must be followed when making a best interests decision:

  1. Will the person regain capacity?
  2. Involve the person.
  3. Consult all relevant people.
  4. Consider all the information.
  5. Do not make any assumptions.
  6. Consider past, present and future wishes.
  7. The very least restrictive option.

The full checklist is in the Mental Capacity Act Code of Practice.

Involve the person you are making a best interests decision for

When a best interests decision is being made the person must still be involved as much as possible.

Mencap and BILD’s Involve Me resource is about creative ways that can be used to ensure people remain at the heart of decision making, and how their preferences can be captured and used to influence decisions about their lives even if they lack capacity to make the decision.

Independent Mental Capacity Advocate (IMCA)

If a person has no family or friends for the decision-maker to consult with on important decisions like serious medical treatment or changes of accommodation, then an Independent Mental Capacity Advocate must represent the person’s views.

They are a legal safeguard for people who lack the capacity to make big decisions. More on Independent Mental Capacity Advocates.

Mental Capacity Act Resource Pack

Download our guide

Download resource Mental Capacity Act resource pack

Power of attorney

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FAQs about the Mental Capacity Act

What does 'mental capacity' mean?

Mental capacity is the ability to make an informed (having appropriate information) decision based on understanding a given situation, the options available, and the consequences of the decision.

Just because someone is not able to make one decision, this does not mean they can’t make other decisions. People should always support a person to make their own decisions if they can do so.

What is a 'best interests' decision?

This means they make the decision on behalf of the person, but in making the decision, they must do so in the person’s ‘best interests’.

They must involve the person as much as possible in working out what the right decision is and involve others who know them well, such as family and friends.

If you are a family carer of someone with a learning disability, you may find our Mental Capacity Act resource pack useful, which you can download to the right.

What if a family member is not being involved when a best interests decision is being made about their loved one?

When making a best interests decision, the decision-maker should involve the person’s family and others who know the person well .

Irwin Mitchell Solicitors have developed a short guide for families in partnership with Ambitious About Autism, Mencap and the Challenging Behaviour Foundation. It explains the rights of families to be consulted when best interests decisions are being made and provides template letters to challenge when this isn’t happening.

See Irwin Mitchell's best interests decision tool.

What if the person’s family don’t think the final decision made is truly in the person’s best interests?

If others do not think the final decision made is truly in the person’s best interests they have the right to challenge it. There are various things that can be done, for example:

  • Ask for an advocate to be involved
  • Ask for a second opinion
  • Make a complaint.

If none of these things work, and there is still a disagreement, the Court of Protection could be asked to decide the matter.

How is capacity assessed?

To have capacity to make a particular decision at a given time a person must be able to:

  1. understand the information relevant to the decision, including the reasonably foreseeable consequences of making or not making the decision
  2. retain that information long enough to make the decision
  3. use or weigh the information as part of the decision making process
  4. communicate the decision in any recognisable way.

Failing any one of the above means the person lacks the capacity to make this decision this time.

What decisions can be made under the Mental Capacity Act?

These can be everyday decisions about what to eat or what clothes to wear - family, carers and support workers may assess capacity often and support people to make their own decisions like this.

Some decisions are more significant such as where to live, how to spend large amounts of money or what medical treatment to have. Professionals may be involved in assessments which include these bigger decisions.

What decisions can't be made?

Decisions that cannot be made for another person under the Mental Capacity Act, include the decision to get married or consenting to sex. Read the Mental Capacity Act Code of Practice for full information on this.

Court of protection deputyship

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Involve me - a practical guide

How to involve people with profound and multiple learning disabilities (PMLD) in decision-making and consultation

Download resource Involve me practical guide

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