What is the Mental Capacity Act (2005)?

The Mental Capacity Act (2005) is a key piece of legislation designed to empower and protect individuals aged 16 and over in England and Wales who may lack the capacity to make certain decisions for themselves.

Understanding mental capacity

Mental capacity refers to a person’s ability to make their own decisions. Under the Act, someone is considered to lack capacity if they are unable to:

• Understand the information relevant to the decision.
• Retain that information long enough to make the decision.
• Weigh up the information to reach a decision.
• Communicate their decision in any way.

Capacity can vary depending on the decision and the timing. For example, someone may have the capacity to decide what to eat for lunch but not to manage their finances. Capacity can also fluctuate due to factors such as illness, mental health conditions, or injury.

The five key principles of the Mental Capacity Act

The Act is guided by five core principles:

1. Assume Capacity – Every adult is presumed to have the capacity to make decisions unless proven otherwise.
2. Right to Make Unwise Decisions – Making a decision that others might consider unwise does not mean a person lacks capacity.
3. Support to Make Decisions – People must be given all possible help to make a decision before concluding they lack capacity.
4. Best Interests – Any decision made on behalf of someone who lacks capacity must be in their best interests.
5. Least Restrictive Option – Decisions should aim to limit a person’s rights and freedoms as little as possible.

How the Act protects individuals

The Mental Capacity Act ensures that:

• Individuals are supported in making decisions about their lives.
• If a person lacks capacity, decisions are made in a way that respects their dignity, rights, and preferences.
• Legal frameworks are in place for important decisions, such as managing finances, healthcare, and accommodation.

Most decisions about care and support

Most decisions about a person’s care and support will be written down in their Support Plan or Needs Assessment. Bigger decisions may require an assessment to agree if someone has capacity to make that decision. These will be for decisions including:

• Admission to hospital, residential, or nursing care.
• Serious medical treatment.
• Where the person lives.
• Managing money and finances.
• Any care, interventions, or treatment where there are different options or opinions.

When a person is assessed as lacking capacity, it will be necessary for a decision to be made on their behalf.

Best interests and decision-making

Any action taken or decision made on behalf of a person who lacks capacity must be in their best interests. The “best interests” process involves:

• Considering the person’s past and present wishes, feelings, and beliefs.
• Consulting with people close to them, such as family members, friends, or carers.
• Avoiding assumptions based on age, appearance, or medical condition.

Sometimes a ‘Best Interests’ meeting is needed, particularly if the decision is significant or people hold differing opinions.

If a person lacks capacity for a very big decision and there is no one who can make it on their behalf, an Independent Mental Capacity Advocate (IMCA) may be asked to assist.

What is the point of a capacity assessment?

A capacity assessment is not about judging the quality or outcome of a decision someone makes—it is about understanding whether they are able to make the decision. The Mental Capacity Act sets clear criteria for assessing capacity. A person is considered able to make a decision if they can:

• Understand the information relevant to the decision.
• Retain that information, even if only for a short period.
• Use or weigh up the information to make an informed choice.
• Communicate the decision, whether verbally, through sign language, or by any other means.

Capacity assessments are decision-specific and time-specific. For example, a person may have the capacity to decide what to wear but might struggle with more complex decisions, such as managing finances.

Are any decisions not covered by the Mental Capacity Act?

The Mental Capacity Act does not apply to certain highly personal decisions or those governed by separate legislation. This ensures that these decisions respect individual autonomy or adhere to specific legal frameworks. Examples of decisions that cannot be made on someone’s behalf include:

• Consenting to marriage or a civil partnership.
• Consenting to sexual relationships.
• Deciding to place a child for adoption.
• Voting in an election.

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