The Mental Capacity Act 2005

The Mental Capacity Act 2005

The Mental Capacity Act (MCA) 2005 came into force in 2007.  It is designed to protect adults who are unable to make decisions for themselves.  It applies to everyone involved in the care, treatment and support of people aged 16 and over living in England and Wales who are unable to make all or some decisions for themselves.  It is designed to protect and restore power to vulnerable people who lack capacity.  It also supports those who have capacity, are over the age of 18, and choose to plan for their future.  All professionals have a duty to comply with the MCA Code of Practice and it also provides support and guidance for less formal carers.  The Act introduces a new criminal offence of ill treatment or wilful neglect of a person who lacks capacity.

A lack of mental capacity could be due to:

  • a stroke or brain injury
  • a mental health problem
  • a learning disability

  • confusion, drowsiness or unconsciousness caused by an illness - or the treatment for it
  • substance misuse.
The 5 principles underpinning the MCA

The MCA is underpinned by 5 key principles:


Presume capacity

It must always be assumed that an adult has the capacity to make his or her own decisions unless it is proved otherwise, as this is their right.  You cannot assume that someone cannot make a decision for themselves just because they have a particular medical condition or disability.


Give all practicable support

Every effort should be made to encourage and support people to make the decision for themselves before anyone treats them as not being able to make their own decisions. If lack of capacity is established, the person should still be involved in making the decision and their views must still be central to the decision.


Unwise decisions

People have the right to make decisions that others might regard as unwise decisions, and it does not mean they lack capacity.  Everyone has their own values, beliefs and preferences which may not be the same as other people's.


Best interests

When an individual lacks capacity to make their own decision, someone must make it in the best way for them. They should do this by consulting with the person and those who know and care for them.


Least restrictive option

When someone makes a decision on behalf of a person lacking capacity they must consider whether there is a less restrictive option, i.e: one that interferes less with the person’s rights and freedoms of action, or whether there is a need to decide or act at all.  Any intervention should be weighed up carefully.


The MCA recognises that lack of capacity may not be a permanent condition.  A person may be unable to make a particular decision at a particular time because their mind or brain is affected by illness or disability. Therefore, assessments of capacity should be time and decision-specific, and must not be based upon age, appearance, condition or behaviour alone.

Two stage test of capacity

Two stage test of capacity

The MCA sets out a two stage test of capacity to determine whether a person lacks capacity to make a particular decision at a particular time. 

Stage 1. Does the person have an impairment of, or a disturbance in the functioning of, their mind or brain?

Stage 2. Does the impairment or disturbance mean that the person is unable to make a specific decision when they need to?

The MCA says that a person is unable to make a decision if they cannot do one or more of the following:

  1. understand information given to them about the decision to be made – ‘relevant information’
  2. retain that information in their mind
  3. use or weigh up the information to make the decision
  4. communicate their decision – this could be by talking, using sign language or any other means.  Every effort should be made to find ways of communicating with someone before deciding that they lack capacity to make a decision based solely on their inability to communicate. Family, friends, carers or other professionals should also be involved.
The role of the IMCA

The Independent Mental Capacity Advocate (IMCA)

The MCA created the role of the IMCA, a statutory safeguard for people who lack capacity to make some important decisions and have have nobody else to support or represent them, or to be consulted (other than paid staff). 

IMCAs must be instructed by local authorities or NHS bodies to support people who are eligible to make decisions about where they live or serious medical treatment.  Local authorities and NHS bodies may also instruct an IMCA to represent eligible individuals in care reviews, where nobody else is available to be consulted; and to support people who are the focus of adult protection proceedings, whether or not family, friends or others are involved. The Deprivation of Liberty Safeguards have introduced further roles for IMCAs.

Other new roles, bodies and powers

Other new roles, bodies and powers

The MCA introduced a new form of Power of Attorney: Lasting Powers of Attorney (LPAs). The LPA allows people over the age of 18 to formally appoint one or more people to look after their health, welfare and/or financial decisions, if at some time in the future they lack capacity to make those decisions for themselves. The Act also created statutory rules with clear safeguards so that people can make a decision in advance to refuse medical treatment if they should lack capacity in the future.

A new court was also introduced, along with a new public official to protect people who lack capacity and to supervise those making decisions on their behalf. The Court of Protection is a specialist court for all issues relating to people who lack capacity to make specific decisions. If an issue is particularly serious and a decision cannot be reached, the court makes decisions and appoints deputies to act on behalf of people who are unable to make decisions about their personal health, finance or welfare.  The Court tailors the powers of the deputy according to the circumstances of the individual.

The role of the Public Guardian was also introduced to protect people who lack capacity from abuse. The Public Guardian is supported by the Office of the Public Guardian (OPG). The OPG maintains a register of LPAs and previous Enduring Power of Attorneys (EPAs). It also maintains a register of the Court-appointed Deputies and is responsible for supervising them.

Click here for more information about our IMCA service.