Under Australian law all adults are presumed to have the capacity (aka competency) to decide whether they wish to receive health care, except when it can be shown that they lack the capacity to do so (Australian Commission on Safety and Quality in Healthcare, 2019).

Informed Consent is a patient’s agreement to specific medical treatment and the requirement to warn of material risk prior to treatment (WA Department of Health, 2016). The common law recognises that there are circumstances where an individual may not be capable of giving informed consent (for example, due to impaired decision-making ability) or where consent to treatment may not be required, as in the case of emergency. State guardianship and mental health legislation also provides detailed rules for substitute decision-making concerning the medical treatment of adults who are deemed incapable of giving consent (Australian Law Reform Commission, 2014).

Consent (or refusal of consent) will be valid if it meets the following criteria:

Consent may be explicit or implied (WA Department of Health, 2016)

• Consent may be implied where a patient indicates through their actions that they are willing to proceed with an aspect of their treatment. Implied consent may apply where significant risks to the patient are not anticipated, e.g. a patient holds out their arm to allow their blood pressure to be taken. If there is doubt about whether the actions of a patient imply agreement to proceed or not, their explicit consent must be sought.
• Where a health professional proposes a higher risk/more complex treatment to a patient, the health professional must seek the patient’s explicit consent (also known as express consent) to that treatment before providing it. The health professional must provide relevant information to the patient, including details of the benefits and risks specific to that patient. This could include invasive procedures or the administration of medication.

Australian law recognises that all persons, unless proven otherwise, have the capacity to make decisions about their healthcare. A person has the capacity to make a decision about their care (including refusal of care) if they can (Australian Commission on Safety and Quality in Healthcare, 2019) (WA Department of Health, 2016)

• Understand the nature, consequences and risks of the proposed treatment (or refusal of treatment), and retain the information needed to make a decision;
• Has all their questions answered;
• Has sufficient time to consider the proposed treatment and its consequences;
• Use the information to make a judgement about the decision; and
• Communicate the decision in some way, including by speech, gestures or other means.

Adult are presumed to have capacity until there are reasonable grounds to conclude otherwise. Examples may include acute medical conditions, effects of drugs or a mental health emergency. Officers may use the Capacity Assessment Tool if the officer is uncertain if the patient can demonstrate the requisite capacity to make an informed decision.

Capacity can be regained. Though incapacity may be permanent in some cases, in other cases it will be temporary; for example if a patient regains consciousness or if they are no longer affected by medication or other substances.

Capacity is decision-specific. Capacity must be relevant to the treatment decision. A person may have capacity to make decisions about simple treatments, but not have capacity to make decisions about more complex treatment with longer term ramifications for their health (WA Department of Health, 2016).

Consent for treatment is not required in an emergency. An emergency is a situation where there is imminent threat to the patient’s health or wellbeing. In all cases where treatment is provided without consent, the treatment must be limited to that which is necessary to save life (the doctrine of necessity).

According to WA Health (WA Department of Health, 2016) in the circumstances where a patient:

• lacks capacity; and
• there is no advanced healthcare directive or common law directive indicating the treatment should not take place; and
• a treatment decision cannot be obtained from a substitute decision maker

Under common law, a health professional may apply treatment and transport necessary in circumstances where it is necessary to:

• to save the patient’s life; or
• to prevent serious damage to the patient’s health; or
• to prevent the patient from suffering or continuing to suffer significant pain or distress.

This does not include treatment necessary due to a mental health emergency as defined in the Mental Health Act 2014 which is discussed below.

WA Health (WA Department of Health, 2016) identifies that a person who has capacity and is 18 years or older can make a ‘living will’ i.e. a document which sets out the person’s health care directives to be followed if the person no longer has capacity to make treatment decisions. Health professionals are obliged to follow treatment decisions expressed in an advanced health directive (AHD) except in limited circumstances. Unless an exception applies, AHDs override decisions made by substitute decision makers.

If the person has communicated their intentions regarding future treatment, this communication may be a valid common law directive if their decision (i) was made when they had capacity, (ii) was made voluntarily (without duress or undue influence), and (iii) clearly applies to the treatment that is proposed.

Treatment should be provided in accordance with decisions expressed in AHDs and generally substitute decision makers cannot override these decisions. If an AHD does not cover the treatment decision to be made, then a substitute decision maker should be identified, as set out in the hierarchy of decision makers under Substitute Decision Makers.

A substitute decision (also known as an enduring power of guardianship) maker may be appointed when a patient lacks capacity. Generally this is done in advance of decisions having to be made, and is done by legal means (Parliament of Western Australia, 1990)

Note that a Power of Attorney has authorisation in relation to an individual’s financial and property matters, not health matters (WA Department of Health, 2008)

The following substitute decision maker hierarchy (Figure 2) is described by the WA Department of Health. The treatment decision should be made by the first person in the hierarchy of decision makers for treatment who is:

• 18 years of age or older
• of full legal capacity
• reasonably available
• willing to make the treatment decision.

Officers should note that healthcare professionals (including paramedics) are not specifically identified in the hierarchy; treatment decisions taken by healthcare providers should relate to those elements covered under the doctrine of necessity which is implemented in an emergency.

A child is anyone under the age of 18 years (WA Parliament, 1972). As a general rule, a parent is legally authorised to provide consent for treatment unless the child has been determined as being able to consent on their own. Where a parent is not present a substitute decision maker may be able to provide consent in a non-emergency situation. However, consent is not required in an emergency.

As children get older their capacity to understand treatment and its consequences increases. A minor who fully understands the nature and consequences of the proposed treatment is capable of effective consent or withholding consent. An assessment of a child as a ‘mature minor’ must be made in the context of the treatment in question, that is maturity in relation to one treatment decision does not necessarily equate to maturity for all treatment decisions. There is no specific age at which a child becomes a ‘mature minor’. The more involved the procedure or more serious the condition the higher the threshold required for understanding for a child (as opposed to an adult) to consent (or refuse) (WA Department of Health, 2016).

The treatment of patients with mental illness is governed by the Mental Health Act 20146 (MHA 2014). A voluntary patient (including referred persons) cannot be provided with treatment without informed consent being given to the provision of treatment.

An involuntary mental health patient or mentally impaired accused who is detained in an authorised hospital, can be provided with treatment without informed consent being given prior to the provision of the treatment (WA Department of Health, 2016). This is not currently within the scope of St John WA.

Sections 202 – 204 of the MHA 2014 allow for emergency psychiatric treatment to be provided to a patient without informed consent where treatment needs to be provided to save the person’s life or where treatment needs to be provided to prevent the person from behaving in a way that is likely to result in serious physical injury to the person or another person. If in the professional opinion of the officer it is important for the patient to go to hospital because of a risk to their life or well-being, the officer must contact the police to ask for their assistance. Police officers have power to compel a person against their will under certain circumstances, by invoking sections of the Mental Health Act 2014 and the  Protective Custody Act 2000. Refer to CPG Disturbed & Abnormal Behaviour for further management information of patients suffering a mental health emergency.

Where a patient is identified as having special language requirements, you may be required to rely on family members or friends, however, professional interpreter services are available through the State Operations Centre.

If friends or family are not available to find out which language interpreter is required, use this tool to assist.

Although family and friends may be helpful in interpreting health information to allow provision of some simple care, generally it is not appropriate to rely on them to interpret more complex health information, including refusal of transport decisions where you have a concern about the patient requiring further assessment.