What is consent?

by TheEditor

Categories: Law, Medicine

This is an exploration of the concept of consent and its constituents. [This page is being updated continuously – last update: 2020-09-20.

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Although ‘consent’ happens frequently in health and social services, a lot of people are not fully aware that it is primarily a legal issue.  Consent is a vast topic – often the focus of PhD theses and many a journal paper. This article cannot possibly touch on every aspect of consent. Best Interests  issues are not covered. This post is relevant to Prescribing Matters. It applies only to consent procedures applicable to adults.

The ‘world of consent’ changed  significantly after the Mental Capacity Act 2005. Then, the Supreme Court (UK) judgment in Montgomery 2015, working it is way though the courts from around year 2000, made the whole thing very serious when £5 million in compensation was upheld. The case was finally decided at the Supreme Court in 2015. None of that means that one has to be a legally qualified to understand the concept.

I avoid deviations into so-called ‘informed’, ‘valid’ and ‘informal’ consent – because the whole legal landscape has changed from 25 years ago. Everybody is entitled to be informed. I cannot understand how consent can be anything but ‘informed’. Can a person give consent if they’re not informed? I do not think so. Today – it is either consent has been achieved or not.  At the end of this article is a list of supplemental materials. This post is relevant to ‘Prescribing Matters‘. It applies only to consent procedures applicable to adults.

Importance of consent

Consent is fundamental to respecting self-determination or autonomy. The Rights of individuals are well protected by several laws, most importantly Human Rights law. Interventions made without consent may constitute an assault or gross breach of individual rights. Such breaches can attract action in both criminal and civil domains of law.

General ideas

Consent among lay people is taken to mean agreement. In other words if you say, “It is fine – take my blood pressure..” that is often taken as consent for a clinician to carry out the procedure. However, in the law of consent to medical procedures it isn’t.  Mere agreement is considered to be ‘assent‘ – which holds little or no legal value. Consent or agreement is also commonly part of everyday life. Lay concepts even among professionals tend to determine attitudes, which then imperceptibly become grafted onto applications of the law. This is a mistake.

Legal concepts

Consent in law, has far deeper meaning than just ‘agreement’. Agreement is also part of the law of contract. There are different ‘types’ of consent in law. Consent to sexual activity with another person is different to consent to treatment with medications or some other medically related procedure.

Consent is only achieved after a capacitous patient communicates a free willing decision of agreement (i.e. without fear, compulsion or undue influence). But early on it is important to keep in mind that in law a patient can refuse to communicate a decision without reason, poor reasoning or being totally irrational. (see Areas of doubt below)

The foundation of consent is ‘capacity’. This is where things get difficult for a significant number of health professionals, from my experience. Part of the difficulty is that capacity (and consent) are primarily legal concepts. There is no ‘medical consent or capacity’ though that may appear as a heading on medical or surgical consent forms. There are only the legal tests of capacity and consent. Clinicians often distance themselves from intricacies of the law, citing ‘I’m not a lawyer‘ as get out. But there is no ‘get out’ or escape from the legalities for two main reasons. 1) Ignorance of the law is not an excuse. 2) Nearly every regulatory body of health professionals requires them to abide by the law.  Every clinician involved in delivering any sort of treatment or intervention, has to know most of the relevant law on consent/capacity. Where they may be lacking, they would do well to seek legal advice.

Unpacking consent

As indicated above consent is necessarily hinged to capacity.

Patients must have the necessary capacity to give valid consent. In England and Wales, the Mental Capacity Act (2005) is used and sets out a statutory test, which states that to be able make a decision, the patient must be able to:

  • understand information relevant to the decision
  • retain that information
  • use or weigh it as part of a decision, AND
  • communicate their decision effectively, by any means.

The Mental Capacity Act is clear that patients should be presumed to have capacity unless it can be established otherwise.

Capacity for treatment decisions

  1. Capacity is a legal test of decision-making ability. It is at the heart of individual autonomy. Rights to self-determination are presumed and protected by several laws.
  2. What is in the patient’s best interests will be a consideration always, but that is not part of the capacity assessment. This often appears surprising to some professionals. However, ‘best interests’ is a separate topic in law after capacity is determined as lost.
  3. A person is presumed to be of capacity unless there is sound evidence to indicate otherwise. Diagnoses of mental disorder do not remove rights to self-determination. There are specific exceptions to that general rule, which are highly regulated by Part IV of the Mental Health Act 1983.
  4. There is nor can there be, any general capacity for treatment. This should become obvious below.
  5. Capacity is person specific – the individual being treated. No comparison with another person or borrowing from another person’s situation is possible.
  6. Save for children, a person cannot consent for another adult – unless by a specific legal provision, usually regulated by strict laws (beyond the scope of this article).
  7. Capacity is treatment specific. This may come down to several factors:
    1. Who is delivering the treatment?
    2. What is the exact treatment? (The treatment isn’t ‘medication’. It is the specific medication(s). Similarly it isn’t ‘surgery’. It is the specific type of surgery and all that flows from the procedure)
    3. Complexity of decisions to be made by the patient based on complexity of information to be processed and weighed in the balance.

Capacity assessment

I had drawn up these questions based on research into case-law and statute law. The questions were adopted in North Wales by Betsi Cadwaladr University Health Board on my recommendation for a capacity assessment form, and implemented after full legal scrutiny. A serious word of caution: the form is not the evidence of capacity. It is only evidence that a capacity assessment took place. As capacity or lack of it, is to be demonstrated it is essential to have robust evidence in documentation on what the findings were. If such an assessment ever comes under scrutiny of the courts, an assessment form will be insufficient.

1.Does the patient demonstrate understanding of the treatment information given (which includes the medical condition/s being treated and proposed specific treatments)?
2.Has the patient retained knowledge of proposed treatment(s) and of any reasonable alternatives, for sufficient time, with aids and assistance in order to form a decision?
3.Does the patient demonstrate awareness of common and material risks of treatment, as explained to them?’ [Montgomery –v-Lanarkshire Health Board * ]
4.Has the patient demonstrated awareness of the benefits of treatment and any relevant limitations or qualifications on beneficial outcomes?
5.Has the patient demonstrated the ability to weigh in the balance relevant benefits against the risks of treatment(s)?
6.Can the patient, with aids or assistance, communicate a decision relevant to this matter?

Material risk is any risk to which a reasonable person in the patient’s position would attach significance (re: Montgomery v Lanarkshire Health Board [2015] UKSC). This could include very rare side-effects and possibilities, which could be important to the patient. Failing to mention to the patient that there could be some uncommon terrible side-effect or adverse outcome (such as death or serious injury), exposes the assessor or treating doctor to risk of litigation if such risk materialises. There is a some acceptance of ‘therapeutic exception’. However, it is burdensome. See ‘Areas of doubt‘ below.

Areas of doubt

In this part address some statements and questions commonly encountered by me over the years. As the context is medical, doctors are referred to. As per disclaimer, this is opinion and not advice.

Montgomery was about shoulder dystocia – nothing to do with the everyday prescribing of millions of medications. 

Doctors may think like that. However, what’s more important is what the Supreme Court thinks. All doctors are required by the GMC to obey the law – even if they are not lawyers. Courts deal with principles of law. Whilst the decisions by the courts may have arisen from a particular situation, the principles decided apply everywhere – unless the courts make an explicit exception. Therefore Montgomery applies to ‘everything’, like it or not.

What if there are several medications – like about 7 – surely the NHS would meltdown if doctors had to go through each medication for side-effects, pros and cons etc.

The law makes no exceptions for service constraints or time availability. A doctor’s duty is to the patient and to carry out the letter of the law. The General Medical Council (GMC) said so; not me.

Sometimes there is an urgent or life threatening situation. There would be no time to address all this.

The law allows for exceptions in situations where there may be immediate needs to protect life or safety. How the law operates in those areas of exception, will need to be known and carefully applied. This comes from studying relevant Statutory guidance and from training. It is not a simple matter of saying ‘There is an immediate  or urgent need‘.

There could be hundreds of side-effects and dozens of complications to cover. How realistic is all this?

Unfortunately the law on capacity/consent is not interested in that. It is what it is. Consent is legal business.  The reality is that there aren’t hundreds of side-effects for a single medication. The British National Formulary will list several for many medications. A prescriber can gain the skill of addressing these in an efficient way. The same applies to potential complications – and the business of explaining benefits.

People almost never remember more than about 5 key facts.

Whilst this is commonly the case, it is possible to group information together in a way that can be recalled by the patient. They do not have to recite what has been told to them; just an understanding and recollection key elements of the facts. So by way of example, extrapyramidal side-effects can be named individually and then grouped together in words such as ‘movement problems I’ve told you about’. The law doesn’t expect the patient to be turned into a doctor in a 15 minute consultation.

What if a person lacks capacity to decide where to live – is it necessary to test capacity to consent to medical treatment?

Yes. There a different kinds of capacities. Capacity is decision-specific. It is possible that a person may lack capacity about where to live but still have capacity to decide about medications.

But other doctors and nurses do not spend as much time with consent. 

Cultural ideas and traditional practice are irrelevant. All who avoid carrying out the correct procedures are wrong. Following deficient practice of others is not sound reasoning, and it is unlikely to be legally accountable.

Sometimes it is obvious that the patient is not of capacity. If they cannot string two words together properly, do we have to go through everything? 

Yes. The burden of proof is on the assessor to show that the person who may appear to lack capacity, has failed to demonstrate it. This is because the law assumes that every adult person is of capacity for everything. This is the starting point. So, if an assessor is finding a lack of capacity on a specific decision-making issue, it is the assessor who has to show how and why. Both the demonstration of capacity and failure to demonstrate it must be carefully documented. If the patient cannot string two words together then careful documentation must be made about what happened in assessing each of the heads of capacity. Read up what the GMC says at para 64 in their guidance.

The patient doesn’t have the intellectual ability to weigh up the information. What then?

Assessors are obliged to assist the patient. After such assistance, with aids where necessary, the other aspects of capacity are assessed.

The patient doesn’t believe anything is wrong with him. He is totally insightless. Obviously he won’t accept medication because it would be pointless from his perspective.

It is settled law that a patient who doesn’t believe anything is wrong with them or the treatment information, can be of capacity. Neither belief nor insight are criteria constituting capacity. The capacity assessment should be attempted to completion, so long as it is safe to do so. A patient could satisfy all the legal criteria for capacity and then refuse to give agreement. The refusal to give agreement means that they have not consented. These issues were settled back in 1994 in the case of Re: C 1994 – where an insightless delusional patient suffering with schizophrenia, believing he was a surgeon, disagreed with real expert surgeons’ advice that his gangrenous ulcerated leg should be amputated (complications of diabetes). The court ruled in favour of the patient. The patient kept his leg and it improved! Read up what the GMC says at para 64 in their guidance.

Sometimes patients refuse to give agreement or reject a proposition for treatment having understood everything. It is irrational and may be caused by delusional ideas or personality disorder. This surely must mean they cannot be of capacity.

There is no general lack of capacity. Firstly the law allows people the autonomy to make unwise or even irrational decisions. Next – irrational rejection of factual information based on delusion, does not mean they lack capacity. This often seems totally weird and without common sense to trainees especially. Importantly, all of these issues have been tested in the courts several times. After distilling all those precedents from the courts, the Mental Capacity Act 2005, codified the principles of capacity. This is how the legal tests have evolved to be defined today (see 45 second video above).

In the case of Re: W 2002, a prisoner suffering with ‘psychopathic disorder’, had inflicted wounds on himself in his lower right leg with a broken lavatory seat. He kept the wound open, forcing various objects into it. The leg became quite infected. W complained of hallucinations, which weren’t seen as part of schizophrenia. He was seen by a consultant surgeon retained by his lawyers. The surgeon suggested amputation but alternatives were discussed. From the judgment:

He said graphically, “I continue to put faeces, metal and other objects in the wound in my leg.” Why does he do it? “I would like to die. I have no support from the prison authorities and hopefully to do this will kill me.” He explained what the surgeon, Mr. McCarthy has said to him about the prospects of what has happened to him. He clearly understood what the choices were from the surgeon. He says, “I hope the consequence will be death. I am aware it will be from blood poisoning, septicaemia and gangrene. Until the Prison Service facilitate medical intervention, which I clearly need, I have stated I do not wish to have treatment to my leg. If I am transferred to a special hospital I would accept treatment.

W was found to have capacity to consent or refuse treatment. The issue in this case was W’s apparent unreasonableness and irrationality, though he may have appeared to have his own manipulative sort of reasoning. The High Court confirmed the finding from Sidaway v Board of Governors of the Bethlem Royal Hospital [1985] AC 871 and Re: MB [1997] EWCA Civ 3093 that “A mentally competent patient has an absolute right to refuse to consent to medical treatment for any reason, rational or irrational, or for no reason at all, even where that decision may lead to his or her own death.” That principle had been confirmed in other cases over the years.

How far does one have to go to assist the patient?

There is no prescription about this. For a patient with cognitive impairment attempts should be made to communicate effectively. Sometimes a relative or carer who is well known to the patient may assist communication. For hearing-impaired patients, it is necessary to use a sign-language interpreter or other appropriate means of communication.

What if the capacity assessment is incomplete because the allocated clinic time has run out (or is running out)? 

There are no exceptions in the law to assume capacity or lack of it, in these situations. Alternative arrangements will need to be made for completing the assessment. Practitioners seeking consent (which includes capacity),  would do well to find the skill and competence to improve the time-efficiency of their assessments. Organisational constraints need to be addressed ahead of consultations so as to ensure sufficient time is available to the patient.

But people may not receive timely treatment and that may cause more complications, when it is obvious that they are not of capacity.

Doing good is not an easy defence for violating the patient’s rights which are particularly protected by Statute. Circumventing capacity assessments on the grounds of harm-avoidance is not a defence either. (There are exceptions for very urgent situations but one has to be very careful with this). Some practitioners may take the chance and construct a capacity assessment when it has not been completed. This is known to happen. It is called dishonesty.

Can I delegate someone else to obtain consent – like a nurse or junior doctor? This was common practice 20 years ago.

The short answer is yes. But the world changed after the Mental Capacity Act 2005. The longer answer is that it depends on whether that person delegated to, will have as intimate knowledge as the doctor prescribing or doing the procedure. What if a doctor delegates to another and some important piece of information is not given to the patient? What if something goes dreadfully and unexpectedly wrong – who gets sued? Note that in Montgomery the compensation figure was £5 million!  Capacity and consent are very specific issues and duties rest primarily with the doctor doing the treatment or in charge of it. The GMC may be more persuasive than me – at para 26 of their guidance and at para 32.

Can any information on risk be withheld from the patient? Some of this can cause distress.

The issue is conceptualised as ‘therapeutic exception’ but it is not to be dealt with lightly. Note that in Montgomery the Supreme court said at para 88, ” The doctor..is entitled to withhold from the patient information as to a risk if he reasonably considers that its disclosure would be seriously detrimental to the patient’s health. The doctor is also excused from conferring with the patient in circumstances of necessity, as for example where the patient requires treatment urgently but is unconscious or otherwise unable to make a decision.” The issue is not simply about distress. The exception can only be made where information is perceived to be ‘seriously detrimental‘. A doctor will be burdened to document what was withheld and to be able to justify how that information was deemed ‘seriously detrimental’. But note also the word ‘reasonably‘. This means that if there is a complication the doctor will be required to show to the satisfaction of a court how his/her considerations were reasonable. The legal expectations of ‘reasonability’ are beyond the scope of this article. For sure it isn’t a matter of what the doctor simply ‘feels is reasonable’.

This is all a bit too much. I treat patients. I’m not a lawyer! 

Saying that in court or at the GMC, may not be a good idea.

Supplemental reading

  1. Consent: patients and doctors making decisions together (General Medical Council)
  2. Flowchart for assessing capacity (GMC)
  3. Re: C 1994 The Independent, Law Report 1993. (Easy read)
  4. The discrepancy between the legal definition of capacity and the British Medical Association’s guidelines  (Journal of Medical Ethics 2003. )
  5. NHS: Consent to treatment
  6. Montgomery – £5 million in damages (the Medical Defence Union)
  7. Montgomery and informed consent: where are we now? (British Medical Journal BMJ 2017;357:j2224)


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