Assessing mental capacity: the Mental Capacity Act

What does the Mental Capacity Act do?

The act protects people who lack the mental capacity to make decisions. Until the Mental Capacity Act 2005 was implemented no statutory law covered this area. Courts previously dealt with capacity under “common law,” which consists of the accumulated judgments of individual cases. The Mental Capacity Act is underpinned by five key principles (box 1), which are illustrated in a hypothetical scenario (box 2).

Why do I need to know about the Mental Capacity Act?

An assessment that a person lacks capacity has major implications; it gives clinicians influence over that person, and this influence could, potentially, be abused. The Mental Capacity Act provides important safeguards to patients’ rights, and it also provides help for clinicians in dealing with capacity problems. In general hospitals, more than 30% of patients on acute medical wards may lack capacity.2 A slightly higher proportion (44%) of psychiatric inpatients lack capacity to make the primary decision for which they were admitted.3 4 Two million people in the UK are estimated to lack capacity through mental illness, learning difficulties, dementia, or physical illnesses that affect brain function (such as delirium or head injury).5

Until now, capacity has mostly been assessed in patients who refuse the management suggested by the clinical team; such patients are often referred to psychiatrists for capacity assessments.6 Clinicians are also often unaware that their patients may have difficulty in making decisions.2 Surveys indicate that clinicians have limited understanding of the law pertaining to capacity.7 8

What has the Mental Capacity Act changed?

Much of the Mental Capacity Act simply codifies previous common law, but it also changes the law in significant ways. The act introduces several new concepts and services: a code of practice; a criminal offence for wilful neglect or ill treatment of people without capacity; an independent mental capacity advocate service; and advance decisions. It has also expanded the role of several existing services, such as the court of protection and frameworks such as lasting power of attorney and court deputies.

What is the code of practice?

The code accompanies the Mental Capacity Act, and it is designed to guide those responsible for interpreting the act.9 Clinicians are legally required to “have regard to” (have read and understood) its guidance and, if later asked, prove they did. Consequently, any departures from this will be hard to justify. The code of practice can be viewed and downloaded online.9

What is the independent mental capacity advocates service?

The service comprises the independent organisations that assign someone to support and represent “unbefriended” people who lack capacity. Their recommendations do not need to be adhered to by clinicians, although they should be taken into account as part of the decision making process. Each local authority (borough) has appointed its own independent mental capacity advocates service.

The code specifies when to instruct an independent mental capacity advocate. They can be instructed for care reviews or adult protection cases, but they must be instructed and then consulted when serious medical treatment is being proposed (such as ventilation, major surgery, chemotherapy, and discontinuation of artificial nutrition or hydration). They must also be involved when accommodation for more than 28 days in hospital or eight weeks in a care home is being arranged or changed.

What is a lasting power of attorney?

This replaces the enduring power of attorney system, where a person could appoint a named person (the “donee”) with the authority to make decisions on their behalf if they lost capacity. Previously this only applied to property and affairs. The Mental Capacity Act widens this authority to decisions about personal welfare, including health care and social affairs. It includes all decisions except those about the withdrawal of life saving treatment, unless explicitly authorised in the agreement. Existing enduring power of attorney agreements will continue as before, but new appointments will be to the lasting power of attorney system.

Property and affairs lasting power of attorney agreements can start before a person has lost capacity, but personal welfare ones cannot. Clinicians treating people without capacity must follow the decision of a donee, unless they are thought not to be acting in the person’s best interests or to be abusing the person lacking capacity, in which case you should follow the guidance of the code of practice. In serious cases you may need to seek a decision from the court of protection.

When making a lasting power of attorney agreement, the limits of the powers granted are specified—this is known as the “nature and effect.” Decisions about life sustaining treatment must be specified in the lasting power of attorney, and a signed statement from the attorney and a certificate completed by an independent third party are required.

A parallel system exists where the court of protection can appoint a deputy for someone who already lacks capacity. The deputy is likely to be a family member or director of social services. The deputy can consent on the person’s behalf but can never consent to decisions that will shorten the person’s life.

What are advance decisions?

Advance decisions can be drawn up by anybody to specify treatments they would not want if they lost capacity. They cannot demand treatments. Provided advance decisions are made when the person had capacity, and they are sufficiently specific to cover the patient’s current predicament, clinicians must respect them. They can be made verbally and can be reversed by the individual if they regain capacity. Advance decisions that refuse life sustaining treatments (such as ventilation) have to be written, signed, and witnessed to be valid. It is incumbent on clinicians to find out if an advance decision exists and assess whether it is valid.

What is the court of protection?

This specialist court has been greatly changed by the Mental Capacity Act. It previously only adjudicated on the financial matters of people without capacity, but its role has widened to include health and welfare decisions. It will be more accessible and available to arbitrate on disputes and is now able to “establish precedent” with the same powers as the High Court.

What legal protection do I have under the Mental Capacity Act?

Section 5 of the act protects from legal liability those providing health care (and personal care) for people without capacity, provided they had “reasonable belief” that the person lacked capacity and their actions were in the person’s best interests. Documentation is key in such situations. However, the act does not protect from liability those professionals who have been negligent, or who have gone against the wishes of an attorney (or deputy) acting within the scope of their power.

How is capacity assessed?

Assessing capacity is a two stage process. For a person to lack capacity, he or she must have an impairment of or disturbance in the functioning of the brain or mind, and this defect must result in the inability to understand, retain, use, or weigh information relevant to a decision or to communicate a choice (figure⇓). Note that there is both a diagnostic threshold and a component that is specific to a decision. Capacity can be assessed only in relation to a specific decision. This has been described as a “functional” approach rather than a “status” approach, where a person—having reached a diagnostic threshold—would be described as lacking capacity for all decisions. Capacity needs to be reassessed for each decision, particularly if the impairments fluctuate over time, as in delirium.

Flow chart of how to decide whether or not a person aged 16 or over has capacity

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Under principle 3 of the Mental Capacity Act, a patient cannot be deemed to lack capacity just because the treating clinicians disagree with his or her decision. People are entitled to make unwise decisions (principle 2)—what matters is not the decision itself, but the way it was reached.

How do I decide what is in someone’s best interests?

When deciding on best interests, you should consider not just the intervention likely to lead to the best clinical outcome, but you should place yourself in the patient’s shoes and ask what they would have wanted if they still had capacity. The views of relatives and others who know the person well may be crucial to making this decision. Clinical problems have a variety of management options, ranging from doing nothing to radical treatments, and the least restrictive option should be used (principle 5 of the Mental Capacity Act).

Restraint can be used to achieve this, but its use is limited by the act (box 3) and it cannot amount to “deprivation of liberty” (see interaction with Mental Health Act).

How do the Mental Capacity Act and Mental Health Act interact?

This is a complex area. The Mental Health Act is relevant only when treating a mental disorder; in most circumstances it is not relevant when treating physical illnesses.

Patients detained under the Mental Health Act who refuse physical health treatments need to have their capacity assessed. Incapacity should not be assumed in such patients (principle 1 of Mental Capacity Act).

Except when a court of protection order—a consequence of which is the deprivation of liberty—is in place, the Mental Capacity Act cannot be used to give care involving deprivation of liberty (see code of practice for details). Treatments that are prohibited in advance decisions or treatments that are not consented to by an attorney can still be given under the Mental Health Act if they are to treat a mental disorder.

The current Mental Health Act (1983) is due to be replaced by a new one (2007) in 2008. Among other changes, it will modify the Mental Capacity Act by clarifying how to deal with patients who lack capacity to decide whether or not to stay in hospital (or a care home), but who do not object to staying. Such patients are referred to as “Bournewood” patients, and the lack of statutory provisions for them is called the Bournewood gap.