Cause of action in trespass
48In the therapeutic context, the defence to the tort of trespass to the person is consent. Where there has been an ostensible consent, which is later challenged, the convenient starting point is to consider the validity of the consent, rather than asking whether it has been obtained by fraud. In principle, consent may be legally ineffective as a result of an innocent mistake or carelessness on the part of the person obtaining it. Further the nature of the consent required is necessary to inform the concept of fraud in this context.
49The modern law with respect to the concept of consent to medical treatment may be traced to virtually contemporaneous developments in Canada, England and in this country. Laskin CJC in the Supreme Court of Canada held that a failure to disclose risks attendant on surgery or other medical treatment does not invalidate the genuineness of the consent, going to negligence rather than battery, "unless there has been misrepresentation or fraud to secure consent to the treatment": Reibl v Hughes [1980] 2 SCR 880; 114 DLR (3d) 1 at [13]. A similar approach, adopted by the Ontario Court of Appeal in Reibl v Hughes (1978) 89 DLR (3d) 112, was followed by Bristow J in Chatteron v Gerson [1981] QB 432. When Sidaway v Board of Governors of the Bethlem Royal Hospital [1984] 1 QB 493 was decided by the English Court of Appeal, Reibl had reached the Canadian Supreme Court and was followed. Dunn LJ adopted the language of Chatterton that "'once the patient is informed in broad terms of the nature of the procedure which is intended, and gives her consent, that consent is real' so that it afford a defence to a battery": at 515D. The reasoning of Bristow J in Chatterton appears to have been first followed in this country by Matheson J in the Supreme Court of South Australia in D v S (1981) 93 LSJS (SA) 405.
50This line of authority has been approved by the High Court in Rogers v Whitaker [1992] HCA 58; 175 CLR 479 at 490, stating that "the consent necessary to negative the offence of battery is satisfied by the patient being advised in broad terms of the nature of the procedure to be performed". Reference was made to the judgment of Bristow J in Chatterton at 443. Commonly, as in Rogers and in Chatterton, the validity of the consent has turned on the adequacy of the explanation given to the patient for the proposed procedure. Both cases were concerned with inadequate disclosures of risks attendant on treatment which were held not to vitiate the consent. However, as Bristow J noted in Chatterton, an action would lie in trespass if, by some accident, the wrong treatment was carried out. He gave an example of a boy admitted to hospital for tonsillectomy who was, through administrative error, circumcised.
51Somewhat different considerations operate in relation to the crime of assault and battery, although it would be a startling result if the medical procedure which was properly characterised as criminal did not give rise to a civil cause of action. In an unlikely case of asserted medical treatment, a man was convicted of rape in respect of sexual intercourse with a 16 year old girl to whom he was giving singing and voice production lessons: The King v Williams [1923] 1 KB 340. The girl's consent was found to have been procured by fraud. The nature of the act to which she consented was, objectively, not medical treatment at all (and he was not a doctor). Nevertheless, cases where doctors have purported to undertake medical procedures for their own sexual or other gratification have also given rise to criminal convictions on the basis that the nature of the act could properly be characterised according to the doctor's motivation or purpose.
52A number of cases subsequent to Williams have been analysed by the Hong Kong Court of Final Appeal in Chan Wai Hung v Hong Kong Special Administrative Region [2000] HKCFA 99; (2000) 3 HKCFAR 288. The cases, involving sexual intercourse or indecent assault, broadly fall into two categories: first, there are cases of sexual activity in respect of which the victim was persuaded that the act involved medical treatment and, secondly, there are cases of conduct which could constitute medical treatment, but which were carried out for an ulterior purpose, usually the sexual gratification of the accused.
53Not all cases, however, have involved sexual assaults. Regina v Richardson [1999] QB 444 involved a dental practitioner who had been convicted on six counts of assault occasioning actual bodily harm, for carrying on practice as a dentist after she had been suspended. The Court of Appeal (Otton LJ, Turner and Dyson JJ) reversed the convictions. After noting that no distinction was to be drawn between sexual and non-sexual assaults, the Court continued at 450:
"The common law is not concerned with the question whether the mistaken consent has been induced by fraud on the part of the accused or has been self-induced. It is the nature of the mistake that is relevant, and not the reason why the mistake has been made. In summary, either there is consent to actions on the part of a person in the mistaken belief that he was other than he truly is, in which case it is assault or, short of this, there is no assault."
54The Court affirmed the general law principle that consent was nullified by deception as to the nature of the act or the identity of the person doing it. The Court declined to extend the latter concept "to cover the qualifications or attributes of the dentist on the basis that the patients consented to treatment by a qualified dentist and not a suspended one": at 450. The Court also rejected concepts derived from the civil law noting that "the criminal and the civil law do not run along the same track".
55In adopting this approach, the Court of Appeal followed the reasoning of the High Court in Papadimitropoulos v The Queen [1957] HCA 74; 98 CLR 249, a case in which the accused was charged with rape on the basis that the woman's consent depended on her (false) belief that the pair had gone through a valid marriage ceremony and that he was, therefore, her husband. The High Court (Dixon CJ, McTiernan, Webb, Kitto and Taylor JJ) stated at 260:
"It must be noted that in considering whether an apparent consent is unreal it is the mistake or misapprehension that makes it so. It is not the fraud producing the mistake which is material so much as the mistake itself. But if the mistake or misapprehension is not produced by the fraud of the man, there is logically room for the possibility that he was unaware of the woman's mistake so that a question of his mens rea may arise. ... For that reason it is easy to understand why the stress has been on the fraud. But that stress tends to distract the attention from the essential inquiry, namely, whether the consent is no consent because it is not directed to the nature and character of the act. The identity of the man and the character of the physical act that is done or proposed seem now clearly to be regarded as forming part of the nature and character of the act to which the woman's consent is directed. That accords with the principles governing mistake vitiating apparent manifestations of will in other chapters of the law."
56The English Court of Appeal in R v Tabassum [2000] EWCA Crim 90; [2000] Cr App R 328 distinguished Richardson on the basis that the Court was there considering an extension to the concept of deception as to the identity of the person performing a procedure. In Tabassum, the victims mistakenly understood that their assailant was medically qualified. The Court held that "they were consenting to touching for medical purposes not to indecent behaviour, that is, there was consent to the nature of the act but not its quality": at 337 [38].
57The criminal law has dealt with the problem caused by fraud or deception inducing consent in different ways. As the English Court of Appeal noted in Richardson, the Law Commission recommended that there should be a new and lesser offence of "obtaining consent by deception" which was to be distinguished from the more serious offence of acting without any consent: Consent in the Criminal Law (1995) (Consultation Paper No 139), par 6.27, quoted in Richardson at 449. In New South Wales, the result in Papadimitropoulos has been reversed with respect to specific offences by providing that a mistaken belief that the accused is married to the victim negates consent to sexual intercourse: Crimes Act 1900 (NSW), s 61HA(5)(b). The section further provides that "a person who consents to sexual intercourse with another person ... under a mistaken belief that the sexual intercourse is for medical or hygienic purposes (or any other mistaken belief about the nature of the act induced by fraudulent means) ... does not consent to the sexual intercourse": s 61HA(5)(c).
58Although in Chatteron Bristow J identified the exception as withholding information in bad faith, constituting fraud, and Dyson J in Appleton referred to the dentist deliberately concealing the truth for financial gain, the reasoning in Papadimitropoulos would appear to establish the correct principle. While the American doctrine of informed consent has not been adopted in Australian law, the requirement of consent is nevertheless founded upon what has been described as a classical expression of principle, articulated by Cardozo J in Schloendorff v Society of New York Hospital 211 NY 125 at 129 (1914), that "[e]very human being of adult years and sound mind has a right to determine what shall be done with his own body; and a surgeon who performs an operation without his patient's consent, commits an assault". That proposition was referred to with approval by the plurality in Marion's Case at 310. Consistently with that principle, a practitioner's honest and reasonable belief that the patient has consented is not a defence to a claim in tort. The absence of consent may flow from the incapacity of the patient, innocent misrepresentation or maladministration by the practitioner or hospital, or fraud on the part of the practitioner or other person responsible for obtaining consent.
59This analysis raises a question as to which party bore the burden of proof. With respect to that issue, there has been remarkably little discussion in Australian case law. In Marion's Case, McHugh J (who was in dissent as to the outcome) stated at 310-311:
"Notwithstanding the English view, I think that the onus is on the defendant to prove consent. Consent is a claim of 'leave and licence'. Such a claim must be pleaded and proved by the defendant in an action for trespass to land.... It must be pleaded in a defamation action when the defendant claims that the plaintiff consented to the publication.... The essential element of the tort is an intentional or reckless, direct act of the defendant which makes or has the effect of causing contact with the body of the plaintiff. Consent may make the act lawful, but, if there is no evidence on the issue, the tort is made out. The contrary view is inconsistent with a person's right of bodily integrity. Other persons do not have the right to interfere with an individual's body unless he or she proves lack of consent to the interference."
60That view would appear to conform to the reasoning of Windeyer J in McHale v Watson [1964] HCA 64; 111 CLR 384 at 388-389, although the issue arose in a somewhat different context. (See also D Mendelson, The New Law of Torts (OUP, 2nd ed, 2010) at 241-242 and RP Balkin and JLR Davis, Law of Torts (LexisNexis, 4th ed, 2009) at [3.7].) However, to the extent that an alternative to reliance on the objective approach is required, this Court should act on the appellant's acceptance that he bore the burden of negativing consent.
61The authorities thus support four broad principles. First, consent is validly given in respect of medical treatment in circumstances where the patient has been given basic information as to the nature of the proposed procedure. However, where the nature of the procedure has been misrepresented consent will be vitiated. Thus, if it were demonstrated, objectively, that a procedure of the nature carried out was not capable of addressing the patient's condition, there can have been no valid consent.
62Secondly, assuming a proposed treatment capable of providing an intended therapeutic effect, for the purposes of determining the effect of a misrepresentation it is necessary to distinguish between core elements, which define the nature of the procedure, and peripheral elements, including risks of adverse outcomes. Absence of advice or wrong advice as to the latter may constitute a breach of the practitioner's duty of care, but will not vitiate the consent.
63Thirdly, the motive of the practitioner in seeking consent to proposed 'treatment' may establish that what was proposed was not intended to be treatment at all, so that the nature of the act to which consent was ostensibly given was not the act carried out. Thus, although the conduct was objectively capable of constituting therapeutic treatment, if it were in fact undertaken solely for a non-therapeutic purpose not revealed to the patient, there will be no relevant consent.
64Fourthly, at least where a real issue has been raised as to the existence of a valid consent, the burden of proof will lie on the defendant practitioner to establish that the procedure was undertaken with consent.
65Much anxious inquiry has been expended on identifying that which constitutes "the nature" of the treatment or, in the language developed in England and Wales, the "nature and quality" of the act: M Somerville, "Structuring the Issues in Informed Consent" (1981) 26 McGill LJ 740; see C Gallavin, "Fraud Vitiating Consent to Sexual Activity: Further Confusion in the Making" (2008) 23 NZUL Rev 87; M Wilson, "Assault in medical law: Revisiting the boundaries of informed consent to medical treatment in South Africa" (2009) 16 JLM 862; The Hon PW Young "Is there any law of consent with respect to assault?" (2011) 85 ALJ 23. In the present case, the difficulty of drawing a clear dividing line between the core elements of the treatment, to which consent must be obtained, and peripheral elements, absence of which will not vitiate consent, does not arise. Rather, the issue is whether treatment which was unnecessary (and now conceded to be so) was presented as necessary (again conceded) so that any apparent consent did not satisfy the criteria for consent to treatment, the treatment in question being unnecessary in the sense that it was not capable of constituting a therapeutic response to the patient's condition.
66It follows from the principles set out above that the concessions made by the dentist are sufficient to demonstrate that the appellant did not consent to the proposed treatment, because it was not in fact treatment necessary for his condition. As a result, the treatment constituted a trespass to the person.
67If, contrary to the foregoing analysis, some kind of fraud is required on the part of the practitioner, I would draw the necessary inference that the dentist was at least reckless as to whether the treatment proposed was either appropriate or necessary for the purpose of addressing the appellant's discomfort, for the reasons given at [47] above in considering the application of s 3B(1)(a).