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When people lack mental capacity

Someone can lack mental capacity if they have an injury, disorder or condition that affects the way their mind works. This could mean they have difficulty making decisions all of the time or that it might take them a long time to make a decision.

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.

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
• 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 you should consider 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)

You must not treat the person as unable to make a decision just because they make decision 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.

• Download 'the Mental Capacity Act 2005 Code of Practice' (PDF, 1131K)

• Help with PDF files

If you need to make decisions for someone else

Any decision you make for someone who lacks capacity must be made in that person's best interests.

When working out what is in someone's best interests there are some common things that you must always consider:

• all relevant circumstances should be considered
• you should make every effort to encourage and enable the person who lacks capacity to take part in making the decision
• if there is a chance that the person will regain the capacity to make a particular decision in the future
• the person's past and present wishes and feelings, beliefs and values
• the views of other people who are close to the person lacking capacity, as well as the views of an attorney or deputy

There are two main ways you can make decisions for someone else:

• as someone’s attorney under an Enduring or Lasting Power of Attorney agreement
• being a deputy appointed by the Court of Protection

These are legal arrangements and can’t fulfil these roles without agreement from the Court of Protection or the Office of the Public Guardian.

Each of these roles has responsibilities and duties you can carry out on behalf of someone else.

• What is a Lasting Power of Attorney?

• Becoming a deputy and your responsibilities