Consent: patients and doctors making decisions together

Legal annex

This section sets out some of the key elements of the law that deal with medical decisions, risk, capacity and consent. It is not intended to be a comprehensive list of relevant case law and legislation, nor is it a substitute for independent, up-to-date legal advice.

The cases cited are all relevant cases heard under English law. Although they are not binding in Scotland and Northern Ireland, they have ‘persuasive authority’, and are generally followed by the courts in these jurisdictions.

Common law


Chester v Afshar [2004] UKHL 41 Pt 2

The duty to warn patients about risk

Ms Carole Chester was left partially paralysed after surgery for lumbar disc protrusion. Dr Afshar had failed to warn Ms Chester that this was a foreseeable (1–2%) but unavoidable risk of the surgery. The House of Lords concluded that, though the failure to warn was not a direct cause of injury, it did result in negligence. In particular, Lord Bingham stated [para 16]:

A surgeon owes a general duty to a patient to warn him or her in general terms of possible serious risks involved in the procedure. The only qualification is that there may be wholly exceptional cases where objectively in the best interests of the patient the surgeon may be excused from giving a warning…In modern law medical paternalism no longer rules and a patient has a prima facie right to be informed by a surgeon of a small, but well-established, risk of serious injury as a result of surgery.

  • Patients should be told of any possible significant adverse outcomes of a proposed treatment.
  • In this case, a small but well-established risk of a serious adverse outcome was considered by the House of Lords to be ‘significant’.

Refusal of treatment

Re C (Adult, refusal of treatment) [1994] 1 All ER 819

The right of a competent adult to refuse medical treatment/The principle that mental illness does not automatically call a patient’s capacity into question.

C had paranoid schizophrenia and was detained in Broadmoor secure hospital. He developed gangrene in his leg but refused to agree to an amputation, which doctors considered was necessary to save his life. The Court upheld C’s decision.

  • The fact that a person has a mental illness does not automatically mean they lack capacity to make a decision about medical treatment.
  • Patients who have capacity (that is, who can understand, believe, retain and weigh the necessary information) can make their own decisions to refuse treatment, even if those decisions appear irrational to the doctor or may place the patient’s health or their life at risk.


Re MB (Adult, medical treatment) [1997] 38 BMLR 175 CA

Capacity to refuse treatment

MB needed a caesarean section, but panicked and withdrew consent at the

last moment because of her needle phobia. The hospital obtained a judicial declaration that it would be lawful to carry out the procedure, a decision that MB appealed.

However, she subsequently agreed to induction of anaesthesia and her baby was born by caesarean section.

The Court of Appeal upheld the judges’ view that MB had not, at the time, been competent to refuse treatment, taking the view that her fear and panic had impaired her capacity to take in the information she was given about her condition and the proposed treatment. In assessing the case the judges reaffirmed the test of capacity set out in the Re C judgement.

  • An individual’s capacity to make particular decisions may fluctuate or be temporarily affected by factors such as pain, fear, confusion or the effects of medication.
  • Assessment of capacity must be time and decision-specific.


Re B (Adult, refusal of medical treatment) [2002] 2 All ER 449

Right of a patient who has capacity to refuse life-prolonging treatment

B was a 43-year-old woman who had become tetraplegic and who no longer wished to be kept alive by means of artificial ventilation. She asked for ventilation to be withdrawn but the doctors caring for her were unwilling to agree to this. B, whose mental capacity was unimpaired by her illness, sought and obtained a declaration from the court that the hospital was acting unlawfully.

  • A competent patient has the right to refuse treatment and their refusal must be respected, even if it will result in their death.


St George’s Healthcare NHSTrust v S; R v Collins and others, ex parte S [1998] 3 All ER 673

The right of a competent pregnant woman to refuse treatment even if that refusal may result in harm to her or her unborn child/Application of the Mental Health Act 1983

S was diagnosed with pre-eclampsia requiring admission to hospital and induction of labour, but refused treatment because she did not agree with medical intervention in pregnancy. Although competent and not suffering from a serious mental illness, S was detained for assessment under the Mental Health Act. A judge made a declaration overriding the need for her consent to treatment, and her baby was delivered by caesarean section.

The Appeal Court held that S’s right to autonomy had been violated, her detention had been unlawful (since it had been motivated not by her mental state but by the need to treat her pre-eclampsia) and that the judicial authority for the caesarean had been based on false and incomplete information.

  • A competent pregnant woman can refuse treatment even if that refusal may result in harm to her or her unborn child.
  • Patients cannot lawfully be detained and compulsorily treated for a physical condition under the terms of the Mental Health Act.


Re T (Adult) [1992] 4 All ER 649

The effect of coercion/pressure on patient consent

T, a 20-year-old pregnant woman, was injured in a car accident and developed complications that required blood transfusions. She did not indicate on admission that she was opposed to receiving transfusions but after spending some time with her mother, who was a practising Jehovah’s Witness, she decided to refuse the treatment.

The Court of Appeal considered that T had been pressurised by her mother and that her ability to decide about the transfusions was further impaired by the drugs with which she was being treated. The Court allowed the blood transfusions to proceed.

  • A patient’s consent to a particular treatment may not be valid if it is given under pressure or duress exerted by another person.

Requests for treatment

Mr Leslie Burke v GMC [2005] EWCA Civ 1003

This case concerned a wide range of issues, most of which related to decision-making at the end of life. However, for the purposes of this guidance, the key point is the Court of Appeal’s opinion that doctors are under no legal or ethical obligation to agree to a patient’s request for treatment if they consider the treatment is not in the patient’s best interests.

Children and young people

Gillick v West Norfolk and Wisbech AHA [1986] AC 112

Children and young people’s competence to consent to treatment

Mrs Gillick challenged the lawfulness of Department of Health guidance that doctors could provide contraceptive advice and treatment to girls under the age of 16 without parental consent or knowledge in some circumstances.

The House of Lords held that a doctor could give contraceptive advice and treatment to a young person under the age of 16 if:

  • she had sufficient maturity and intelligence to understand the nature and implications of the proposed treatment
  • she could not be persuaded to tell her parents or to allow her doctor to tell them she was very likely to begin or continue having sexual intercourse with or without contraceptive treatment
  • her physical or mental health were likely to suffer unless she received the advice or treatment
  • the advice or treatment was in the young person’s best interests.

This case was specifically about contraceptive advice and treatment, but the case of Axon, R (on the application of) v Secretary of State for Health [2006] EWHC 37 (Admin) makes clear that the principles apply to decisions about treatment and care for sexually transmitted infections and abortion, too.

  • As a result of this decision, a young person under 16 with capacity to make any relevant decision is often referred to as being ‘Gillick competent’.


Making decisions when patients lack capacity

England and Wales

Mental Capacity Act 2005

This Act provides a legal framework for making decisions in relation to people who lack capacity. It clarifies:

  • who can make decisions, including decisions about medical care and treatment, for people who are unable to decide for themselves
  • how those decisions should be made.

Section 1 of the Act sets out five statutory principles that apply to any action taken and decisions made under the Act. These are:

  1. a person must be assumed to have capacity unless it is established that they lack capacity
  2. a person is not to be treated as unable to make a decision unless all practicable steps to help him do so have been taken without success
  3. a person is not to be treated as unable to make a decision merely because he makes an unwise decision
  4. an act done, or decision made, under the Act for or on behalf of a person who lacks capacity must be done, or made, in his best interests
  5. before the act is done, or the decision is made, regard must be had to whether the purpose for which it is needed can be as effectively achieved in a way that is less restrictive of the person’s rights and freedom of action.

In this Act, people lack capacity in relation to a particular matter if, at the material time, they are unable to make a decision for themselves in relation to the matter because of an impairment of, or a disturbance in the functioning of, the mind or brain (section 2(1)).

Doctors and other healthcare professionals must have regard to the supporting Code of Practice, which explains how the Act should work on a day to day basis and sets out the steps that those using and interpreting it should follow when:

  • assessing a person’s capacity, or
  • reaching a decision in the best interests of a person who does not have capacity.

Mental Capacity Act 2005

Mental Capacity Act Code of Practice


Adults with Incapacity (Scotland) Act 2000

This Act provides ways to help safeguard the welfare of people aged 16 and over who lack the capacity to take some or all decisions for themselves, because of a mental disorder or inability to communicate. It also allows other people to make decisions on their behalf. The Act provides various methods of intervening (that is, taking decisions or action) on behalf of an adult who lacks capacity, including in relation to healthcare. The Act sets out the principles that must be followed when deciding whether to intervene.

Any intervention must be:

  • necessary and must benefit the person
  • the minimum necessary to achieve the purpose.

Those making decisions must:

  • take account of the person’s present and past wishes and feelings, and must try every possible means of communicating with the person to find out what these are
  • take into account the views of the person’s nearest relative and primary carer, and of any other person with powers to intervene in the person’s affairs or personal welfare, or with an interest in the person, so far as it is reasonable and practical to do so
  • encourage the person to use any skills they have to make decisions consider whether it would be possible to intervene without using the Act.

In this Act, incapacity means being incapable of acting on, making, communicating, understanding, or remembering decisions by reason of mental disorder or inability to communicate due to physical disorder.

The Act is supported by Codes of Practice setting out guidance for those acting under the legislation, including doctors and other healthcare professionals who are treating adults with incapacity. Part 5 of the Code of Practice covers decisions about medical treatment and research.

Adults with Incapacity (Scotland) Act 2000

Scottish Government site for the Act

Northern Ireland

There is currently no primary legislation on capacity covering Northern Ireland. Decisions about medical treatment and care when people lack capacity must be made in accordance with the common law, which requires decisions to be made in a person’s best interests.

The Bamford Review of Mental Health & Learning Disability (N.Ireland) which produced its final report in August 2007 recommended that there should be a single comprehensive legislative framework for the reform of mental health legislation and the introduction of capacity legislation in Northern Ireland.

On 2 January 2009, the Northern Ireland Department of Health, Social Services and Public Safety (the Department) issued a consultation document, Legislative Framework for Mental Capacity and Mental Health Legislation. As a result of the consultation, the Department is now leading work on a single bill covering mental capacity and mental health to be introduced into the Northern Ireland Assembly in 2011.

The Bamford Review of Mental Health & Learning Disability (N. Ireland)

Delivering the Bamford Vision: The Response of NI Executive to the Bamford Review of Mental Health and Learning Disability, Action Plan 2012–2015

Use of human tissue

England, Wales and Northern Ireland

Human Tissue Act 2004

The Act requires that consent is obtained before:

  • a person’s organs and tissue can be stored or used for purposes such as research, post-mortem examination, and transplantation
  • a deceased person’s organs and tissue can be removed for these purposes.

The Act specifies whose consent is needed and in what circumstances. The Human Tissue Authority (HTA) publishes a Code of Practice which gives detailed advice on how consent should be obtained and recorded.

Human Tissue Act 2004

Human Tissue Authority website – Codes of Practice


Human Tissue (Scotland) Act 2006

The Act requires that authorisation is obtained before a deceased person’s organs and tissue can be stored or used for purposes such as research, post-mortem examination, and transplantation. It does not cover the use and storage of tissue from living people, other than organ donation for transplantation.

Human Tissue (Scotland) Act 2006

Fertility Treatments

Human Fertilisation and Embryology Act 1990 (as amended by the Human Fertilisation and Embryology Act 2008)

This Act provides a legal framework across the UK for all those involved in fertility treatments. It defines the rights of donors, patients and the children who may result from the treatment, restricts research on human and human admixed embryos to specified purposes and places time limits on the storage of embryos, eggs, and sperm. The Human Fertilisation and Embryology Authority (HFEA) was created under the Act to oversee the licensing and compliance of treatment clinics and research centres and to keep new developments under review.

Human Fertilisation and Embryology Act 1990 (as amended)

Human Fertilisation and Embryology Act 2008

Human Fertilisation and Embryology Authority website

Human Rights

The Human Rights Act 1998

The preamble to the Human Rights Act 1998 (HRA) describes it as ‘an Act to give greater effect to rights and freedoms guaranteed under the European Convention on Human Rights’ (the Convention). The HRA only incorporates the rights in Articles 2 to 12 and in Article 14 of the Convention, plus those in the First and Sixth Protocols. The incorporated rights are set out in the First Schedule to the HRA and are referred to as ‘Convention rights’.

As far as it is possible to do so, primary legislation and subordinate legislation must be read and given effect in a way that is compatible with these Convention rights.

The HRA requires that all public bodies must ensure that everything they do is compatible with the Convention rights unless an Act of Parliament makes that impossible. They must provide a way for people to challenge a public body if they believe it has acted, or proposes to act, in a way that is unlawful under the HRA.

The Convention Articles most likely to be relevant to decisions about medical investigations and treatment are:

  • Article 2 (the right to life)
  • Article 3 (the right to be free from inhuman or degrading treatment)
  • Article 8 (the right to respect for privacy and family life)
  • Article 10 (the right to freedom of expression, which includes the right to hold opinions and to receive information)
  • Article 14 (the right to be free from discriminatory practice in respect of these rights).

Ministry of Justice Human Rights pages