The High Court of Australia has been busy today on the Torts front, handing down 2 fairly significant decisions. In this email I will discuss the more general one on medical negligence, and if I get the chance later today will discussion the slightly narrower decision on Malicious Prosecution.

In Wallace v Kam [2013] HCA 19 (8 May 2013) http://www.austlii.edu.au/au/cases/cth/HCA/2013/19.html the plaintiff consented to to an operation without being warned of two risks of quite distinct physical harm which might eventuate (a risk of nerve damage and a separate risk of paralysis). The risk of nerve damage materialised, the more serious risk of paralysis did not. The Court accepted findings (or assumptions) made below that if warned of the nerve damage risk alone, the plaintiff would probably still have agreed to go ahead with the procedure. But if given both warnings that should have been given, he would not have undertaken the procedure. Could the doctor be held liable in these circumstances for the eventuation of the nerve damage risk, which the plaintiff would have accepted?

The joint judgment of 5 members of the Court is, with respect, a particularly lucid analysis. The analysis of s 5D of the CLA 2002 is especially clear and helpful, although the decision is still of great relevance on general common law principles. In effect the Court confirms what many of us have been saying:

1. That s 5D(1)(a) is simply the "but for" test, is there a historical connection with the harm? See [16]

2. That s 5D(1)(b), which requires the question to be answered, "is it appropriate for the scope of the negligent person's liability to extend to the harm so caused", is to be answered by considering previous common law decisions:

"[22] In a case falling within an established class, the normative question posed by s 5D(1)(b) is properly answered by a court through the application of precedent. Section 5D guides but does not displace common law methodology. The common law method is that a policy choice once made is maintained unless confronted and overruled."

Here it was accepted that "but for" causation was established- the plaintiff would, on the facts, not have gone ahead with the operation had both warnings been given, which should have been given. However, the "normative" question was whether it was appropriate for the doctor's liability to extend to a consequence which the plaintiff, if warned, would have accepted as a possible outcome. Reference was made to the well-known mountaineer example and the Court in the end agreed with the majority in the NSWCA that liability should not extend to this outcome. In the end, as the Court said, while it sounds somewhat glib: "Mr Wallace should not be compensated for the materialisation of a risk he would have been prepared to accept"- [32].

Other important points are made in what I consider to be a very clear analysis. A distinction is drawn between a case where a number of separate risks of the same physical harm are present, and the current one, where the two risks were independent of each other- see [33]-[35] citing a Scottish decision I had not come across before. The law is not compensating Mr Wallace for interfering with his freedom of choice, or for the "increased risk" of harm he suffered; the compensation is for the physical injury- [39]. US decisions are cited which accord with this view. Prof Stapleton's scholarship is extensively cited, as are article from other list members.

Regards

Neil