Consent and special needs patients: a review

It is well accepted in the medical and dental profession that consent is required for every procedure undertaken, be it an examination or a more invasive procedure such as a dental extraction or surgical intervention. This consent may be oral, written or implied. However, every procedure carries a list of risks and benefits, and it is the responsibility of every clinician to obtain informed consent – giving the patient all the available information, including risks and benefits of treatment along with any alternatives.

Informed consent requires:

• All relevant information to be given to the patient

• The patient must be capable of making the decision

• The decision must be voluntary.

Capacity to consent is the duty of the clinician and he/she must ensure that the patient has the relevant capability. It is a part of the clinicians’ duty of care to the patient and a failure to do so could be seen as negligent.

Legal rules concerning the capacity to consent have historically acted as a protective mechanism for those persons who for one reason or another are considered to be unable to give informed, legal consent. Capacity refers to the ability of a person to perform a given task.

Parents generally have joint legal guardianship of a child and their estate while they are under the age of 18 and have the legal ability to make decisions concerning the minor’s welfare. When a person has reached the age of 18 years, parents or guardians cease to have a legal right to make decisions on their behalf.

The law operates with a presumption of capacity unless this is refuted. Some adults suffer from a temporary or permanent impairment of their decision-making capacity – those with an intellectual disability, dementia, psychiatric illness, acquired brain injury or inability to communicate their decision. These adults will be referred to as vulnerable for the purpose of this article.

A vulnerable adult may be able to consent to a minor procedure such as dental examination but not to a procedure with more wide ranging connotations such a general anaesthesia for a dental clearance. In the legal context, capacity is a threshold requirement for persons to have the ability to make decisions concerning their own welfare. Autonomy and self-determination are the pivotal keystones upon which human independence is based, and a finding that an adult lacks capacity results in the restriction or complete loss of basic human rights (Law Reform Commission Consultation Paper, 2005).

In re a Ward of Court (No. 2), which was a Supreme Court case concerning the withdrawal of feeding from a woman who had been in a persistent vegetative state (PVS) for more than 20 years following complications during a gynaecological operation, Hamilton CJ stated: ‘The loss by an individual of his or her mental capacity does not result in any diminution of his or her personal rights recognised by the Constitution, including the right to life, the right to bodily integrity, the right to privacy, including self determination, and the right to refuse medical care or treatment. The ward is entitled to have all these rights respected, defended, vindicated and protected from unjust attack and they are in no way lessened or diminished by reason of her incapacity’.

There has been an increased interest in the concept of consent in relation to the vulnerable adult in Ireland. The question of who, if anybody, has the legal authority to consent on behalf of another person over the age of 18 years has been debated, particularly in the fields of medicine and dentistry.

The number of patients with some degree of mental disability seeking care from the community or general dental services is rising (Bridgman AM et al, 2000). There are 25,416 people in Ireland with an intellectual disability, including 7,730 in residential care (Crowley E et al, 2003). Senior citizens constitute a significant portion of the population and although the majority of over 65s are not mentally ill, depression and dementia are of significant concern.

This article will address consent, focusing on consent in relation to an adult with limited powers of decision-making, and discuss recent recommendations by The Law Reform Commission in this area.

Assessment of capacity

The merit of a patient’s agreement to treatment is that it recognises his or her entitlement to make his or her own decision (Bridgman AM et al, 2000). For a person’s consent to be valid, he or she must be:

• Capable of taking that particular decision (competent)

• Taking the decision in a voluntary capacity

• Provided with the necessary information to enable them to make the decision (informed consent) (Department of Health, 2001).

It is accepted that consent is implied in many cases by the fact that the patient has come to the doctor/dentist for treatment. The Irish Medical Council has clear guidelines regarding informed consent: ‘Informed consent can only be obtained by a doctor who has sufficient training and experience to be able to explain the intervention, the risks and benefits, and the alternatives. In obtaining this consent the doctor must satisfy himself/herself that the patient understands what is involved by explaining in appropriate terminology. A record of this discussion should be made in the patients’ notes’ (Irish Medical Council, 2004).

The Irish courts have no single definition of capacity, but have indicated in a variety of different cases that an adult is presumed to have legal capacity unless otherwise proven. Other jurisdictions have varying policies: in Victoria, Australia, capacity is defined in terms of ‘lack of capacity’, in the United States the movement is towards ‘measurement of the ability to function in society’ and in Canada capacity is defined as the ‘ability to understand information relevant to making a decision’ (Law Reform Commission Report, 2006).

The presumption of capacity accommodates the notion of fluctuating capacity and lucid intervals. This renders the assessment of the capacity to make a healthcare decision fraught with unpredictability. Doctors and dentists make such assessments on a daily basis but there is little guidance available. There is also a disturbing lack of consensus in the medical profession as to how capacity is assessed. Tests such as the Mini-Mental State Examination (MMSE) (where a patient’s orientation, registration, attention, calculation, recall and language are tested), and the Wechsler Adult Intelligence Scale (designed by David Wechsler to test verbal and performance skills in different age groups) are useful, but should not determine the ability to make healthcare decisions.

The British Medical Association has published a Consent Tool Kit to help with these decisions. To show capacity, the patient should be able to:

• Understand in simple language what the medical treatment is, its purpose and

nature, and why it is being proposed

• Understand its principal benefits, risks and alternatives

• Understand in broad terms what will be the consequences of not receiving the

proposed treatment

• Retain the information for long enough to use it and weigh it in the balance in order to arrive at a decision.

Scotland’s Adults with Incapacity Act 2000 resulted in the setting up of a code of practice on medical treatment that assists medical practitioners to assess an adult’s capacity to make a healthcare decision. A wide range of factors are considered, including whether the person:

• Is capable of making and communicating their choice

• Understands the nature of what is being asked and why

• Has memory abilities that allow the retention of information

• Is aware of the alternatives

• Has knowledge of the risks and benefits involved

• Is aware that such information is of personal relevance to them

• Is aware of the right to, and how to, refuse, as well as the consequences of refusal

• Has ever expressed their wishes relevant to the issue where greater capacity existed

• Is expressing views consistent with their previously preferred moral, cultural, family and experiential background.

The endeavour to find a functioning standard of competency has been portrayed as ‘a search for the holy grail’ (Roth et al, 1977). Wong and Clare investigated three approaches to determining capacity: status, outcome and functional (Wong et al, 1999).

The status approach

The status approach is a generalised approach to capacity that assesses the patient by his/her disability rather than taking into the account the seriousness of the decision to be made. This approach defines capacity using the membership of a specific group or population, or through the possession of certain distinct characteristics. Thus all adults are presumed to have capacity while children do not.

Historically, the medical profession, along with society in general, has regarded those with a mental illness as deficient in the necessary decision-making power to give informed consent and this view is still widely held. This puts the responsibility on the patient with a mental illness to establish his/her capacity rather than enjoying the presumption of capability. It has the capability of operating in a prejudicial manner in respect of those with a varying capacity, such as those with long periods of capacity interspersed with periods where rational thought is impaired by mental illness. However, critics of this approach are reminded that there are cases where capacity is seen to be permanently absent such as in the case of PVS (persistent vegetative state) or advanced dementia, and it would be unnecessary to reassess the capacity of these patients every time consent is necessary (Law Reform Commission Consultation Paper, 2005).

The principal problem with the status approach is that it assumes uniformity within a particular group and this approach has been rejected in case law (Scottish Executive, 2000).

The outcome approach

Outcome as a measure of capacity makes an assessment based on the repercussions of the patient’s decision. The result of this decision is taken as an indicator of the patient’s capacity. This approach holds the patient’s choice up to conventional wisdom and the greater the deviation, the higher the probability of a finding of incapacity. This restricts individuality and there is a greater danger of a finding of incapacity if a patient rejects a doctor’s advice.

Lack of capacity is just one explanation of a patient’s dismissal of advice: they might not want the treatment, be poorly informed or be unable to make a decision because of anxiety (Bellhouse J et al, 2001). The courts have found that a patient’s decision may well reflect the presence or absence of understanding but is not an automatic indication of capacity (Law Reform Commission Consultation Paper, 2005).

The functional approach

This is the most widely respected model of capacity, and is based on demonstrating the extent to which the patient’s competence meets the requirements involved in making the decision.

This involves an assessment of their level of comprehension and communication ability, and relating these to the particular task, thus making the notion of capacity both time and situation specific (Scottish Executive, 2000).

Capacity is seen to be specific to each decision and although some people will lack the capacity for all decisions, for example those in a coma, others suffer from a more limited impairment and will be capable of making certain decisions. Therefore it is not appropriate to undertake a standardised assessment but rather to narrow an individual judgement to the decision to be made.

When an individual is found to lack competence, this approach allows an attempt to improve capacity through education, changing the format of the information presented – i.e. in pictures rather than words – or treating the underlying condition. The irony of this can sometimes be found in that treating the condition may well be the issue requiring consent. The functional model of capacity is in direct contrast to the all-or-nothing approach employed under the status approach.

Integration of approaches

The functional and outcome approaches may be combined to form a sliding scale, the limit depending on the significance of the decision. Another arrangement combines status and function so that capacity is questioned only in certain groups – although this can be seen as discriminatory against these groups. It is, however, the approach suggested by The Law Commission in England and Wales and in Scotland (Scottish Executive, 2000)

Mechanisms to address loss of capacity

The existing legal régimes to deal with an adult who lacks capacity are wardship and enduring powers of attorney.

The ward of court régime is a substitute decision-making system for adults under Irish law, with a paternalistic approach to consent. The President of the High Court has responsibility for the system and can delegate to the registrar and staff of the Office of Wards of Court. The procedure for bringing a patient into wardship is accessible in the Lunacy Regulation Act 1871.

Wardship proceedings are usually carried out in respect of people who have a significant loss of capacity and who have an estate that requires protection and use in the best interests of that patient. The patient must be declared to be of ‘unsound mind and incapable of managing his person or property’. This must be supported by two medical doctors and the term ‘unsound mind’ is necessary for the matter to proceed. Capacity is assessed on an all-or-nothing basis. An inquiry order is made and a consultant psychiatrist will examine the person. Notice is served on the patient, who has the right to submit any objections in writing to the Registrar.

Declaring a person a ward of court results in a substantial loss of decision-making capacity, and it is significant that a ward of court is not entitled to consent to medical treatment.

The Law Reform Commission has identified a number of problems with the wardship regime: ‘The wards of court system is cumbersome and outdated, the language is inappropriate and the procedures involved are lengthy. Legislation does not deal with how decisions about the person of the ward are to be made.’

An adult who is a ward of court can apply to the President of the High Court to be discharged from wardship. If medical proof of a restoration in the patient’s legal capacity is adequate, control of their person and property will be returned to the patient.

An Enduring Power of Attorney (EPA) allows an adult with sufficient capacity to plan for a future loss of capability under the Powers of Attorney Act 1996. This will allow another adult or a solicitor to make decisions on behalf of the patient if they experience a substantial loss of the requisite capacity, thus avoiding the necessity for them to be made a ward of court at a later date and retaining as much autonomy as possible for the patient. However, an EPA can only be executed by an adult with the appropriate mental capacity and may be unsuitable for adults with an intellectual disability.

The EPA can vary, with the patient in a position to give the appointed person power over property, financial and personal care decisions, or a combination of the above. Personal care decisions do not include decisions on medical and surgical treatment. The Law Reform Commission has recommended that persons appointed under an EPA have the same power as those proposed for personal guardians i.e. minor or emergency healthcare decisions, unless specifically withheld by the patient (Law Reform Commission Report, 2006).

If the EPA does not give sufficient powers, wardship proceedings may still be necessary, and the courts have the power to invalidate any EPA in that case.

Recommendations have been made by the Law Reform Commission regarding the current wards of court system and its replacement by the guardianship system involving two proposed orders: intervention and guardianship orders.

An intervention order would become relevant where a person has some capacity but requires intervention in a minimal way. A guardianship order would be relevant where a person lacks capacity and requires the help of another person to make decisions. A guardianship board rather than a court should make decisions regarding an individual’s capacity, with appeals directed to the High Court. This board should be multi-disciplinary including doctors, psychiatrists, psychologists, social workers, lawyers and lay persons.

The establishment of a new, independent Office of Public Guardian is recommended, which would organise substitute and assisted decision-making on behalf of vulnerable adults. This office would take over most but not all of the functions currently carried out by the Registrar of Wards of Court. The Office should be separate to the courts and headed by the Public Guardian, who would be an independent office holder.

A guardianship order would involve the appointment of a Personal Guardian to make decisions on behalf of an adult who lacks capacity. It is recommended by the Law Reform Commission that this should be a spouse or family member who should consider first and foremost the best interests of the vulnerable adult.

The Personal Guardian should have the power to give consent to any necessary routine medical treatment. Certain major healthcare decisions such as non-therapeutic sterilisation would not fall within the remit of the Guardianship Board and would be reserved for the High Court (Law Reform Commission Report, 2006).

Previously, legal precedent regarding emergency treatments has been laid down according to the common law doctrine of consent. It does not replace informed consent but rather provides a defence for the clinician.

The Council of Europe lays down four principles:

1. Intervention on a person who is unable to consent should only be carried out for his/her direct benefit

2. Intervention must be authorised by their ‘representative’ or a body provided for by law

3. The previously expressed wishes of the person must be taken into account

4. When, because of an emergency situation, the appropriate consent cannot be obtained, any medically necessary intervention may be carried out immediately for the benefit of the individual involved (Council of Europe, 1997).

Under the law of torts, treatment without consent may lead to a claim for trespass to the person, while under the Non-Fatal Offences Against the Person Act 1997 it may constitute an assault.

Role of the family

It is a widespread practice among medical professionals that an adult who lacks the capacity to consent will have a consent form signed by a next of kin as a risk management strategy. It is legally binding that a person under the age of 16 must have a parent or legal guardian consent on his/her behalf. However, when an adult lacks the capacity to make healthcare decisions, no other adult is legally entitled to consent on their behalf. It is considered good practice to involve next of kin in any healthcare decisions and to have an assent form signed, but this is more a public relations exercise than any legal safeguard.

Problems will arise when there is a disagreement between relatives as to whether or not to consent, or if relatives disagree with the clinician regarding the best interests of the patient. It has been shown that relatives consistently choose a lower level of intervention than the patients would themselves (O’Neill D, 1997).

The Irish Medical Council states that: ‘A wide ranging consultation involving parents/guardians and appropriate carers should occur. Where necessary, a second opinion should be considered before decisions on complex issues are made.’

As most vulnerable adults in Ireland are not wards of court, they are treated by most doctors and dentists on the basis of consulting widely. However, this practice is divergent with the law.


This review has discussed in depth the situation in Ireland regarding informed consent in relation to adults with a limited decision-making capacity.

The Law Reform Commission would prefer to define capacity with a view to people as individuals and not on the basis of labels such as mental disorder (Law Reform Commission Report, 2006).

It is obvious that anomalies exist in the law and at the moment clinicians are relying on a number of measures – i.e. widespread consultation and the signing of consent forms by next of kin – to overcome these problems. However, it has become clear that these procedures, while considered good practice, would not provide legal justification if a treatment was to be challenged in court (Dickenson D, 2001).

Decisions regarding treatment are usually based on issues of quality of life and technical futility. Technical futility is important, as every patient deserves the opportunity of specialist referral (O’Neill D, 1997).

The only safe ground for the clinician is within the wardship of court system, where the courts will make healthcare decisions for the patient.

The doctrine of necessity is also heavily relied on to provide a defence in relation to the carrying out of procedures on vulnerable adults. Irish law does not clearly lay out the concept of necessity but it is often taken in the broad sense – e.g. if an adult who is unable to consent to treatment requires a filling and is likely to experience pain in the tooth if the restoration is not placed, this could be seen as a necessity. Therefore routine treatment can be considered a necessity, as well as emergency treatment for trauma, sepsis or pain.

The doctrine was tested in the Irish law Courts in 1937 in the case of Holmes v Heatley. In this case a young boy had a local anaesthetic administered to allow for a minor operation. Consent was taken from his parents. The boy became unco-operative before the end of the procedure and a GA had to be administered to complete the suturing. The patient died under GA. A claim was brought by the parents on the basis that a GA without consent amounts to assault and battery. The High Court decided that the GA was necessary in an emergency situation and the surgeon had a legal defence.

It is obvious that reform is necessary in Irish law and the healthcare professions need to be taken out of the legal limbo they face when dealing with consent and the vulnerable adult. As the Law Reform Commission has decided, a uniform, statutory definition of capacity is necessary.

A functional approach to capacity is recommended with appropriate terminology that recognises the dignity of all human beings. Capacity should be based on an adult’s ability to understand the nature and consequences of a decision in the context of available choices at the time the decision is to be made. The paternalistic approach so favoured by Hippocrates is now obsolete, and it is not the duty of the medical professional to protect the patient from information (Jones B, 2000).

The Commission recommends that a person will lack capacity if they are unable to communicate in any way with a third person, when this is necessary to implement the decision. It would be appropriate to enact legislation to provide a substitute decision-maker who could, among other roles, make healthcare decisions. The Commission also recommends that this new legislation should give powers to the Minister for Health to appoint a working group that would lay down a code of practice for healthcare professionals.

It would resolve the present situation where some medical professionals will only carry out procedures relating to the life or death of the patient, and others rely on the doctrine of necessity to carry out all routine treatment (Law Reform Commission Consultation Paper, 2005).

It would benefit both the patient and the clinician if there was a clear procedure for consent in relation to the vulnerable adult, and this reform is long overdue in Ireland.


Bellhouse et al (2001) Decision-making capacity in adults. APT 7: 295-301

Bridgman AM, Wilson MA (2000) The treatment of adult patients with mental disability. Part 1: Consent and duty. BDJ 189(2): 66-68

Bridgman AM, Wilson MA (2000) The treatment of adult patients with a mental disability. Part 2: Assessment of competence. BDJ 189(3): 143-146

Council of Europe (1997) Convention for the protection of human rights and dignity of the human being with regard to the application of biology and medicine. Oviedo. 4 IV

Crowley E, Whelton H et al (2003) Oral health of adults with an intellectual disability in residential care in Ireland. Department of Health and Children

Department of Health UK (2001) Seeking consent: working with older people. Department of Health Publications, London

Dickenson D (2001). Decision-making competence in adults: a philosopher’s viewpoint. Advances in Psychiatric Treatment 7: 381-387

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Law Reform Commission (2006) Report. Vulnerable adults and the law. LRC 83

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Wong JG, Clare ICH et al (1999) Capacity to make healthcare decisions: its importance in clinical practice. Psychological Medicine 29: 437-446

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