Close the Dictionary; Statutory test for “irrationality”

The Court of Appeal has cautioned against resorting to a dictionary to interpret a statutory term. Rather, context and purpose are the central arms of statutory construction. This featured in South Western Sydney Local Health District v Gould [2018] NSWCA 69. It concerned the application of the proper legal test for section 5O of the Civil Liabilty Act 2002 (NSW). Their Honours found that Levy DCJ erred in applying the legal test for irrationality in section 5O(2) and that its application was procedurally unfair. They held that section 5O applied and there was no liability in negligence.

The judgment is here. Leeming JA provided the main judgment with Basten JA and Meagher JA agreeing.

Section 5O Civil Liability Act 2002 (NSW)

Section 5O was introduced following recommendations in the Ipp Report. It contains the standard of care for professionals, such as doctors. Its effect is that a professional is not liable in negligence if the professional acted in a manner that is widely accepted by peer professional opinion as competent professional practice. But a court is not bound by the peer professional opinion if it considers the opinion to be irrational.


The respondent, a patient, was 8 years old. He presented at Campbelltown Hospital with an open fracture to his thumb. Antibiotics were administered to protect his open fracture from bacteria. He was then transferred to Liverpool Hospital. There he was also administered antibiotics but not an additional antibiotic. He underwent surgery the following morning. He was discharged shortly after. Two weeks later, he developed gangrene. It required amputation of his thumb. He alleged that the failure to administer the additionalantibiotic amounted to a breach of a duty of care which caused the infection that resulted in the loss of his limb.

Primary Decision

The experts considered that the treating staff at Liverpool Hospital acted in manner that was widely accepted in Australia by peer professional opinion to be competent professional practice. Notwithstanding, the primary judge found that these views were “irrational” on the basis that they were made “without soundly based supporting reasoning”. He was not prepared to accept the protection afforded under section 5O.

On appeal

Procedurally unfair

That the decision rested upon section 5O was held to be procedurally unfair. Multiple reasons underscored this. Section 5O(2) (irrationality) had not been pleaded and nor was it mentioned in trial or in submissions. Irrationality was in no way a part of the Plaintiff’s case. One of the experts whose view was considered “irrational” had been not been required for cross examination and all of his evidence was accepted without objection.  No party made submissions that his opinion was irrational.  It came as a “complete surprise” that the entirety of his evidence was found to be irrational by the primary judge.  It was also procedurally wrong for the primary judge to reject the evidence as irrational when no complaint was made about it by the Plaintiff, and no warning was given to the Defendant (or to the experts).

Erroneous reasoning

The primary judge misapplied the legal test for irrationality. He said that “irrational” did not mean “without reasons” but “reasons that are illogical, unreasonable or based on irrelevant considerations”. He gave no explanation for that construction. He then gave dictionary definitions of “unreasonableness”, namely, “without sound or logical reasons, or not endowed or guided by reason”. About this misapplication of the test, Leeming JA said (at [77]):

This is a relatively extreme example of reliance of dictionaries as a substitute for applying the principles of statutory construction. It led to error.

Close the Dictionary

Leeming JA provided an interesting exegesis into statutory interpretation and the limited circumstances in which resort to dictionary based definitions is desirable. Dictionary definitions say little, if anything, about how that term is to be understood in any particular situation. Similarly, the meaning of statutory language is not accomplished by choosing one meaning from a dictionary definition of what is said to be a synonym of the statutory text. In many contexts, the words are not true synonyms, notwithstanding their cognate etymologies. The primary judge had erred by resorting to definitions of “unreasonable” (nor did he refer to definitions of “irrational”). Leeming JA provided (at [79] – [81]):

The legal meaning of a statutory term is but rarely assisted by resort to a dictionary definition…The High Court have approved …the statement…to the effect that a mature and developed jurisprudence does not “make a fortress out of the dictionary” [in Commissioner of Taxation v BHP Billiton Ltd [1] Residual Assco Group Ltd v Spalvins[2] and Thiess v Collector of Customs [3] ). The fact that one of the meanings in a dictionary may support the legal meaning of a statutory term chosen by a court does little to provide a basis for a conclusion as to legal meaning. It often does no more than to provide the illusory comfort that the court’s construction is supported by common usage…

A dictionary will give a range of meanings of a word. The task of a court is to identify, from text, context and purpose, the particular meaning that a statutory provision bears. The function of a dictionary and the function performed by a court construing a statute are utterly different. It must be borne in mind that the meaning of any word used in a statute depends on the context and purpose of the legislation in which it appears: Coverdale v West Coast Council [4] 

That dictionaries tend to be unhelpful is accepted in modern Australian appellate courts. Mason P said that dictionaries “can illustrate usage in context, but can never enter the particular interpretative task confronting a person required to construe a particular document for a particular purpose”: House of Peace  at [25]. In Minister for Immigration and Multicultural Affairs v Khawar [5]  Kirby J candidly acknowledged that he was “now inclined to see more clearly than before the dangers in the use of dictionary definitions”, principally because of the need to have regard to context and purpose.

A dictionary may assist if a question truly arises as to the meaning of a word, especially if it is an historical meaning (in House of Peace, the question was whether use as a “church” in a 1954 development consent comprehended use as a mosque). It may also be accepted that a dictionary may assist a court in identifying the full range of literal meanings a statute might bear, although it is unlikely that modern statutes, which tend to be drafted by parliamentary counsel, will use language that requires resort to a dictionary definition. But even in cases where a dictionary might assist at the outset, the court’s task is not accomplished by surveying the range of meanings found in a dictionary and choosing that which seems most apt. Doing so may often disguise the real reasons which favour a particular legal meaning. As McHugh J said in Kelly v The Queen [6] , “The literal meaning of the legislative text is the beginning, not the end, of the search for the intention of the legislature.”

Proper interpretation

Instead of resorting to a dictionary, what is required in statutory construction is regard to the text together with the legislative context and purpose, with context being regarded at the first stage and in its widest sense. [7] Leeming provided (at [83]):

The approach taken by the primary judge meant that … no attempt [was made] to identify context or purpose. His Honour disregarded the extrinsic materials, which are relatively rich and speak directly to why “irrational” was chosen to qualify the “defence” for which s 5O made provision. His Honour was not assisted by the parties, but they are certainly not to blame, because at no stage were they given an opportunity to be heard as to the proper construction of a section which had not at any time been invoked.

The text, context and purpose of “irrational” in s 5O(2)

The following was held as to the proper construction of section 5O(2) (at [84] – [85]):

“Irrational” is a strong word as a matter of ordinary English. It is unquestionably pejorative in this context…

The section must be read as a whole. Subsection 5O(2) is to be read with subsections (3) and (4). It will be seen that s 5O proceeds on the basis that there may be more than one widely held body of peer professional opinion, each inconsistent with the other, but none of which is necessarily irrational. Adherence to any of those bodies of peer professional opinion – so long as it is widely accepted in Australia – would render a professional defendant not liable. Perry J made the point in Piwonski v Knight [8] that it was impossible for a surgeon to adopt every procedure which some but not all competent surgeons recommended, because some were mutually inconsistent alternatives. That does not mean that any of the mutually inconsistent views was irrational. To the contrary, it emphasises the strength of a conclusion that peer professional opinion is irrational

Nor is the test for irrationality under s 5O(2) satisfied when the basis for a practice is unexplained, or, as the primary judge put it, “oracular”. Competent professional practice to administer lime juice to treat and to ward off scurvy amongst sailors preceded by many decades any understanding of the role of vitamins in human health. The fact that the reasons given in the late 18th and 19th centuries for the practice were wrong, or non-existent, did not make the practice irrational. (It was known to work).

[1] [2011] HCA 17.

[2] [2000] HCA 33 at [27].

[3] [2014] HCA 12 at [23].

[4] [2016] HCA 15 at [18].

[5] [2002] HCA 14 at [103]-[111].

[6] [2004] HCA 12 at [98].

[7] (at [83] and referring to ZTAL v Minister for Immigration and Border Protection[2017] HCA 34 at [14], [35]-[40] and [82]).

[8] [2002] SASC 310 at [74].


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