Mental Capacity Act (MCA) 2005


The Mental Capacity Act 2005 provides the legal framework for acting and making decisions on behalf of individuals who lack the mental capacity to make particular decisions for themselves.  Everyone working with (and/or caring for) an adult who may lack capacity to make specific decisions, must be able to provide evidence of compliance with the principles of the Act.  This rule applies whether the decisions are life-changing events or everyday matters.

Core principles

The Mental Capacity Act (MCA) is built on five statutory principles that guide and inform all decision making in relation to the estimated two million people who may lack capacity in some aspect of their lives.  The MCA underpins health and social care commissioning and practice.

The core principles are as follows:

  1. A person must not be assumed to lack capacity UNLESS it is proved otherwise.
  2. Until all practical steps have been taken to help someone make a decision, without success, they cannot be treated as lacking capacity.
  3. An unwise decision does NOT in itself indicate lack of capacity.
  4. Any act or decision made must be in the person’s best interests.
  5. Any act or decision should aim to be the least restrictive option to the person in terms of their rights and freedom of action.

Who is affected?

The Act applies to any person who has a condition that causes an impairment of, or disturbance in the functioning of the mind or brain.  This might include somebody with dementia, learning disabilities, brain injury (for example, stroke or physical trauma to the brain), mental health problems, autism or confusion (for example, from an infection or due to substance misuse).


The Mental Capacity Act 2005 defines lack of capacity in the following way:

A person lacks capacity in relation to a matter if, at the material time, he is unable to make a decision for himself in relation to the matter because of an impairment of, or a disturbance in the functioning of, the mind or brain.

Capacity is decision and time specific.  Capacity assessments refer to a person’s ability to make a particular decision at a particular moment in time, they are not a blanket judgment on a persons ability.


When applying the MCA, certain categories of people are legally required to have regard to relevant guidance contained in the MCA code of practice.

These people include anyone acting in a professional capacity for, or in relation to, a person who lacks capacity, and anyone being paid for acts for, or in relation to, a person who lacks capacity.

Deprivation of Liberty Safeguards (DoLS)

The Mental Capacity Act Deprivation of Liberty Safeguards (MCADoLS) were introduced into the Mental Capacity Act 2005 through the Mental Health Act 2007 (which received Royal Assent in July 2007). The MCADoLS came into force 1 April 2009.

The MCA DOL safeguards apply to anyone aged 18 and over, who has a mental disorder or disability of the mind – such as dementia or a profound learning disability - who lacks the capacity to give informed consent to the arrangements made for their care and/or treatment, and for whom deprivation of liberty is considered to be necessary in their best interests to protect them from harm.

The safeguards cover patients in hospitals, and people in care homes registered under the Care Standards Act 2000, whether placed under public or private arrangements.

The safeguards are designed to protect the interests of an extremely vulnerable group of service users, and to:

  • Ensure people can be given the care they need in the least restrictive regimes.
  • Prevent arbitrary decisions that deprive vulnerable people of their liberty.
  • Provide safeguards for vulnerable people.
  • Provide them with rights of challenge against unlawful detention.
  • Avoid unnecessary bureaucracy.

A Deprivation of Liberty (DoL) refers to a restriction of an individual’s freedom such as physical restraint or constant supervision. The DoLS are a set of legal requirements which ensure that individuals are only deprived of their liberty in a necessary and proportionate way and provide protection for individuals once a DoL has been authorised. The safeguards relate to adults aged 18 and over who are deprived of their liberty in a hospital or care home. They only apply to individuals who have a mental health condition and lack the capacity to make decisions about their care.

One of the key safeguards is that organisations must apply for the authorisation to deprive someone of their liberty. The authorisation process involves completing an application form which is sent to the local Council with Adult Social Services Responsibilities (CASSR or council). The council organises the relevant assessments and these inform the decision to either grant or not grant the authorisation. There are 6 criteria that must be assessed and fulfilled for the authorisation to be granted. Details about the applications, assessments and the individuals involved are recorded by councils and then submitted to the Health and Social Care Information Centre (HSCIC) through the DoLS data collection.


The MCADoLS Acid Test - Deprivation of Liberty after the Cheshire West case.

The six requirements remain the same following the Cheshire West judgement; the following six conditions must be met. The person must:

  1. Be 18 years and over;
  2. Have a mental disorder;
  3. Lack capacity for the decision to be accommodated in the hospital or care home;
  4. Not have made a decision, when they had capacity, to refuse treatment or care;
  5. Not be ineligible for DoLS;
  6. Need to be deprived of liberty, in their best interests.

The difficulty comes in working out whether a situation in a hospital or care home amounts to a deprivation of liberty.

The Supreme Court has now confirmed, in response to the Cheshire West case, that there are now two key questions to ask – these questions form the ‘acid test’:

  1. Is the person subject to continuous supervision and control? (All three aspects are necessary AND
  2. Is the person free to leave? (The person may not be saying this or acting on it but the issue is about how staff would react if the person did try to leave.)

So this now means that if a person is subject both to continuous supervision and control and not free to leave they are deprived of their liberty. 

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