Informed consent is both a legal requirement and a core professional obligation. To be valid, consent must be voluntary, given by a competent person, and based on adequate information — including material risks. The landmark Rogers v Whitaker decision and the High Court’s approach to material risk disclosure sets the standard in Australia. Documenting consent properly is your most important protection when a complaint arises.
Informed consent is one of the most litigated and complained about areas of medical practice. Allegations of inadequate consent — ‘the doctor didn’t tell me that could happen’ — are among the most common bases for medical negligence claims and AHPRA complaints in Australia.
Part of the challenge is that consent is not a form — it is a process. A signature on a piece of paper does not prove that informed consent was obtained. Conversely, the absence of a written consent form does not mean consent was invalid. Understanding the legal framework — and what it actually requires — is essential for every practitioner.
The Legal Standard: Rogers v Whitaker and the Material Risk Test
The foundational Australian case on informed consent is Rogers v Whitaker (1992) 175 CLR 479, a decision of the High Court of Australia. In that case, the Court established that a doctor has a duty to warn patients of any material risk involved in a proposed treatment.
A risk is ‘material’ if:
- A reasonable person in the patient’s position would be likely to attach significance to the risk; or
- The doctor knows or ought reasonably to know that the particular patient would be likely to attach significance to it
This is a two-part test — objective and subjective. It is not enough to warn only about statistically significant risks. If there is any reason to believe this particular patient would want to know about a specific risk — even a rare one — the duty to disclose arises.
The High Court’s approach was reinforced in Rosenberg v Percival (2001) and, most importantly, in Wallace v Kam (2013), which dealt with the limits of causation in consent cases. Most recently, the law has continued to evolve in ways that further strengthen the patient’s right to be informed.
Key Legal Principle: The standard for consent disclosure is patient-centred, not doctor-centred. You cannot defend a failure to warn by arguing that ‘most doctors wouldn’t have told the patient about that risk.’ The question is whether this patient would have wanted to know. When in doubt, disclose.
The Five Elements of Valid Consent
For consent to be legally valid in Australia, it must satisfy five core requirements:
- Capacity: The patient must have decision-making capacity at the time consent is given. An adult patient is presumed to have capacity unless there is evidence to the contrary. Capacity is decision-specific — a patient may have capacity to consent to one procedure but not another.
- Voluntariness: Consent must be freely given, without coercion, undue influence, or duress. This includes subtle forms of pressure — for example, a patient who feels they have no real choice, or who has been made to feel that declining would have adverse consequences.
- Information: The patient must have received sufficient information to make an informed decision. This includes the nature and purpose of the procedure, material risks and side effects, available alternatives (including the option of no treatment), and likely consequences of not proceeding.
- Comprehension: The patient must have understood the information provided. Language barriers, health literacy, emotional distress, or the complexity of the information can all affect comprehension. It is not enough to recite risks if the patient cannot understand them.
- Agreement: The patient must have actively agreed to the procedure. Silence or passivity is not consent.
Written vs Verbal Consent: What Does the Law Require?
There is no universal legal requirement in Australia for written consent for all medical procedures. However, for significant invasive procedures — particularly surgical procedures — written consent is both best practice and standard of care in most clinical contexts.
The practical position is as follows:
- For routine procedures and general practice consultations, verbal consent (properly documented in the clinical notes) is typically adequate
- For surgical procedures, anaesthesia, significant diagnostic procedures (e.g., lumbar puncture, cardiac catheterisation), and procedures with material risks, a written consent form is standard
- Written consent forms are not legally conclusive — they are evidence of the consent process but do not replace the need for a proper discussion
- Hospital and practice policies may impose additional requirements — always comply with institutional requirements in addition to the legal minimum
Documenting Consent: What Your Notes Must Show
In any complaint or legal claim involving consent, your clinical notes are your primary evidence that a proper consent process occurred. Good consent documentation should include:
- That the procedure was explained, including its purpose and nature
- The specific risks and side effects that were discussed
- That alternatives were discussed, including the option of no treatment
- That the patient was given an opportunity to ask questions
- That the patient appeared to understand the information
- That the patient agreed to proceed
- If a consent form was used, that it was completed, signed, and retained in the record
A note that simply says ‘consent obtained’ or ‘patient agreeable to procedure’ is generally insufficient. You should record, at minimum, the key risks discussed and the patient’s expressed understanding.
Clinical Scenario: The Undisclosed Risk: Dr Chen performs a relatively routine procedure — a nerve block for shoulder pain. She discusses the main risks (infection, bruising, incomplete effect) but does not mention the rare risk of pneumothorax, which occurs in fewer than 1 in 1000 cases. The patient develops a pneumothorax and lodges a complaint.
The question: Was this a material risk that should have been disclosed? Under Rogers v Whitaker, the answer may well be yes — a pneumothorax requiring hospital admission and possible intervention is exactly the kind of outcome that a patient would attach significance to, regardless of its statistical rarity. Dr Chen should have documented the risks discussed in detail. Her best defence would have been a contemporaneous note recording that she advised of the pneumothorax risk, and the patient acknowledged this and wished to proceed.
Key lesson: In any procedure with potentially serious (even if uncommon) complications, disclose those complications and document that you have done so.
Consent for Minors
Consent for medical treatment of children and young people is one of the most legally complex areas of consent law. The key principles are:
Children Under 18 — Parental Consent
As a general principle, parents or legal guardians provide consent for medical treatment of children under 18. Where both parents hold parental responsibility, either parent can generally consent to routine medical treatment, but both should consent to major procedures where practicable.
Gillick Competence / Mature Minor Doctrine
A child below the age of 18 may be capable of consenting to their own medical treatment independently of their parents — if they have sufficient maturity and intelligence to understand the nature and consequences of the proposed treatment. This is sometimes called ‘Gillick competence’ (from the UK case) or the ‘mature minor’ doctrine.
In assessing whether a minor has the competence to consent, consider:
- Their age and maturity
- Their ability to understand the nature of the treatment and the consequences of not treating
- Whether the decision is consistent with their welfare
Note: Australian courts have held that even a Gillick-competent minor may require parental (or court) approval for major or irreversible treatments. The threshold for accepting a minor’s independent consent rises with the seriousness of the treatment.
Disputed Consent Between Parents
Where parents disagree about whether a child should receive medical treatment, and the matter cannot be resolved, the question may need to be referred to a court or child welfare authority. In urgent situations where delay would endanger the child, you can provide emergency treatment without parental consent.
Consent and Decision-Making Capacity
For adult patients who lack decision-making capacity, consent must be obtained from a substitute decision-maker. The hierarchy of substitute decision-makers varies by state but generally follows this order:
- A person holding an Enduring Power of Attorney (medical treatment decisions)
- A court-appointed guardian
- A close family member or unpaid carer, in order of relationship (spouse/partner, adult child, parent, sibling)
In NSW, the person responsible framework under the Guardianship Act applies. In Victoria, the Medical Treatment Planning and Decisions Act 2016 governs substitute decision-making. Equivalent legislation exists in each state and territory.
In an emergency, where a patient lacks capacity and there is no time to identify or consult a substitute decision-maker, you may provide treatment necessary to prevent serious harm or death. Document the emergency circumstances carefully.
Withdrawal of Consent
A competent patient has the right to withdraw consent to treatment at any time — even mid-procedure, if it is practicable to do so. This is a fundamental principle of autonomy. The obligation to respect a patient’s withdrawal of consent does not disappear because a procedure is already underway.
Practically, this creates genuine difficulty in some surgical contexts. The obligation is to stop if you can do so without causing greater harm than continuing. If stopping mid-procedure would itself cause injury, the clinical and ethical calculus is more complex, and you should document the circumstances in detail.
Consent for Telehealth Consultations
The expansion of telehealth raises specific consent issues. Key points:
- Patients should be made aware of the limitations of telehealth — including that the absence of a physical examination may affect clinical assessment
- For telehealth consultations involving procedures that would ordinarily require written consent (e.g., initiating certain treatments, obtaining consent for a subsequent in-person procedure), the consent process should mirror the standard applied to in-person consultations
- Record in the clinical notes that the consultation was conducted via telehealth and that the patient was informed of the telehealth format
Frequently Asked Questions
Q: A patient signed a consent form before surgery, but later claims they didn’t understand the risks. Am I protected by the signature?
A signed consent form is evidence that a consent discussion occurred — not conclusive proof that the consent was informed and valid. If the patient can show they did not understand the risks, or that the risks were not adequately explained, the signature alone may not be enough. Your clinical notes recording the risks discussed are as important as the form itself.
Q: Does consent need to be renewed if a significant period of time passes before a procedure?
Yes, as a matter of best practice. If a patient consented to a procedure some time ago but circumstances have since changed — new information about risks, a change in the patient’s condition, or a significant delay — the consent should be reviewed and reconfirmed. Do not rely on stale consent.
Q: Can a patient refuse treatment that would clearly save their life?
Yes — a competent adult patient has the right to refuse treatment, even life-saving treatment. The right to refuse is one of the most fundamental expressions of patient autonomy under Australian law. Your obligation is to ensure the patient has the information to make an informed refusal (including the consequences of refusing), and to document that discussion. You cannot override a competent patient’s refusal.
Q: What about patients with cognitive impairment — does any capacity mean full consent capacity?
No. Capacity is decision-specific and can fluctuate. A patient with early dementia may have capacity to consent to a simple procedure in a good period but not to a complex one. Assess capacity for each decision, at each presentation, using an appropriate assessment framework. If capacity is borderline or uncertain, documenting your assessment process is essential.
Q: Is consent required for a physical examination?
Yes. Every physical examination requires consent — even a routine one. Implied consent (the patient presenting for examination) covers routine examination; express verbal consent is appropriate for more intimate examinations. For genital, breast, or rectal examinations in particular, explicit verbal consent should be obtained and documented every time, regardless of prior examinations.
