Table 2

Mental capacity legal framework in UK jurisdictions

UK territoryLegal basisTest of capacityProxy decision- makersAdvance decisions
England and Wales5 6Mental Capacity Act 2005A person is unable to make a decision for himself if he has impairment of, or a disturbance in the functioning of, the mind or brain and this means that he is unable to:

  1. understand the information relevant to the decision

  2. retain that information

  3. use or weigh that information as part of the process of making the decision, or

  4. communicate his decision (whether by talking, using sign language or any other means)

 		Lasting power of attorney relevant to Health and Welfare
Court appointed deputy		The Mental Capacity Act 2005 allows a person over 18 with capacity to make an advance decision to refuse treatment.
Valid and applicable advance decisions to refuse treatment must be respected.
If they relate to life-sustaining treatment then they must be in writing, signed and witnessed.
Scotland7 8Adults with Incapacity (Scotland) Act 2000‘Incapable’ means incapable of:

  1. acting, or

  2. making decisions, or

  3. communicating decisions, or

  4. understanding decisions, or

  5. retaining memory of decisions

by reason of mental disorder or of inability to communicate		Welfare powers of attorney
Guardian		A competently made advance statement made orally or in writing to a practitioner, solicitor or other professional person would be a strong indication of a patient's past wishes about medical treatment but should not be viewed in isolation from the surrounding circumstances.
An advance directive to refuse specific treatment may be binding and is described as “potentially binding” in the code of practice which recommends that advice be sought.
Northern Ireland9Common lawA person is unable to make a decision for himself if he has impairment of, or a disturbance in the functioning of, the mind or brain and this means that he is unable to:

  1. understand the information relevant to the decision

  2. retain that information,

  3. use or weigh that information as part of the process of making the decision, or

  4. communicate his decision (whether by talking, using sign language or any other means)

 		Not applicableAn advance decision to refuse treatment may well be valid under the common law.

  • 1. Specific mental capacity legislation is enacted in England and Wales (The Mental Capacity Act 2005) and Scotland (Adults with Incapacity (Scotland) Act 2000). Legislation relating to mental capacity and mental health (The Mental Capacity Bill) is proceeding through the legislative process in Northern Ireland. That remains a common law jurisdiction but the principles remain very similar to those codified in the Mental Capacity Act 2005. There are, however, no provisions related to welfare attorneys.

  • 2. Although the approach taken to adults who lack capacity by the Mental Capacity Act 2005 and the Adults with Incapacity Act 2000 is similar, there are some important differences. For example, in Scotland the ‘General Power to Treat’ part 5 of the Act gives a general authority to treat a patient who is incapable of consenting to the treatment in question, on the issuing of a certificate of incapacity. The general principles of the Act must be applied by the practitioner who issues such a certificate and gives treatment under it. The common law authority to treat a patient in an emergency remains in place.

  • 3. The principle of ’best interests’, though expressed differently, applies in all jurisdictions. Common law, the Mental Capacity Act 2005 and the Adults with Incapacity Act 2000 expect that people's wishes (including those expressed when the patient had capacity even if not in the form of an advance decision) should be taken in to account and that the practitioner should consult widely with those who have an interest in the patient's welfare. The holders of a relevant power of attorney that covers the treatment must of course be consulted.