25 Finally, the Commissioner argued that his construction accorded with the evident purpose of the PSO Act referred to in the Regulation Impact Statement contained in the Explanatory Memorandum, namely to encourage the recycling of unconsumed used oil that otherwise would be disposed of and present a significant and growing environmental hazard.
26 For the following reasons, the Commissioner's construction is not accepted.
27 The word "including" in a definitional clause can serve a number of different functions. Ordinarily, where "includes" is used in a statutory definition it may have either or both of two functions: to extend the ordinary meaning of the particular word to bring within the scope of the meaning of that word something that otherwise would not be encompassed by it (Re Gray; Ex parte Marsh (1985) 157 CLR 351, 364-365; [1985] HCA 67 at [18]; Zickar v MGH Plastic Industries Pty Limited (1996) 187 CLR 310; [1996] HCA 31); and/or to avoid possible uncertainty as to whether something may come within the definition by expressly providing for its inclusion (Corporate Affairs Commission (SA) v Australian Central Credit Union (1985) 157 CLR 201, 206-207; [1985] HCA 64 at [5]; BHP Billiton Iron Ore Pty Ltd v National Competition Council (2008) 236 CLR 145, 159; [2008] HCA 45 at [32]). The word "includes" can also provide an exhaustive explanation of the meanings to be attached to the word if the context in which the word appears reveals that intention: YZ Finance, 398-399, 402. See also Pearce DC and Geddes RS, Statutory Interpretation in Australia (8th ed, LexisNexis Butterworths, 2014) at [6.60]-[6.63].
28 In YZ Finance the question was whether the appellant had a right to sue on a promissory note pursuant to s 24(1) of the Money-lenders and Infants Loans Act 1941 (NSW). Whether it had that right depended upon whether the action was a proceeding for the enforcement of a "security" made or taken to secure the payment of the money lent and interest. "Security" was defined in s 24(2) as follows:
In this section 'security' includes bill of sale, mortgage, lien, and charge of any real or personal property, and any assignment, conveyance, transfer or dealing with any real or personal property to secure the repayment of any loan.
The majority (McTiernan, Kitto, Taylor and Windeyer JJ, Menzies J dissenting) had regard to the legislative context and held it was consistent with the evident purpose of s 24(1) to read the definition of "security" in s 24(2) as an exhaustive definition of the types of the securities to which s 24(1) applied, where those securities all shared as their common element the right of recourse against specific property.
29 In the present case, there are a number of textual and contextual reasons for concluding that Parliament did not intend the words in parentheses to be exhaustive of the petroleum based oils which are "oils" for the purposes of the PSO Act.
30 First, the items enumerated as "petroleum based oils" include "greases". Mr Winn's evidence was that a grease is not an oil. Mr Winn explained as follows at [36]-[38] of his affidavit:
A grease is produced by combining a base oil or lubricant base oil…, a thickening agent and various additives. In the majority of cases the thickening agent is commonly referred to as "soap". The base oil or lubricant base oil usually makes up about 80-95% of the grease, the thickening agent usually makes up about 5-20% and the remainder is made up of the additives.
Greases are semi-solids. This means that they are neither a liquid nor a solid. Its natural state lies somewhere in between and, in that state, a grease will not move. But if you "push" a grease, it will move. Greases will become softer as the temperature rises, and will become a liquid when the melting point of the thickener is exceeded.
A grease is not an oil. This is because an oil, in its natural state, is a liquid. Liquids will start to move at the slightest pressure, force or stress. A grease on the other hand will not move until the force or stress exceeds a certain amount when they give way. There is a spectrum of greases, ranging from very hard greases to very soft greases, but the key point of difference between a grease and an oil is that at almost zero pressure, a grease does not move whereas an oil will.
(Emphasis added.)
31 Senior counsel for the Commissioner argued that grease nonetheless is apt to be included in the list because grease contains 80% to 95% lubricant base oil and the only reason it is not a liquid is because thickener is added to it. It was further argued that a grease can be a liquid when heated to a sufficient temperature. Significantly though, whereas the other products enumerated in the parentheses are all oils or oil-based fluids, grease is not, or at the least may not normally be, regarded as an oil. The inclusion of greases tends to indicate that the function of the word "including" in this context was not intended to indicate an exhaustive explanation of the meaning of "petroleum based oils" in the context of the PSO Act, but rather to expand the meaning of "petroleum based oils" to include greases or at least to make clear that the expression covers greases.
32 Secondly, the items enumerated as "petroleum based oils" do not cover all possible forms of non-fuel petroleum based oils. Mr Winn gave as an example a lubricant to be used as a "machine tool slideway" lubricant. If the Commissioner's construction is accepted, this type of lubricant would not be an "oil" for the purposes of the PSO Act. Mr Winn's evidence also was that products other than lubricants are made from base oils produced from crude oil, such as white oil, crop oil and mould oil. If the Commissioner's construction is accepted, these types of oils would also not be "oils" for the purposes of the PSO Act. Senior counsel for the Commissioner sought to distinguish these types of oils by arguing that they are oils that are not apt to produce waste because they are wholly consumed by their very use and so, the argument went, are not "oils" in respect of which benefits under the PSO Act are intended to be available. Such an argument, however, gives the expression "petroleum based oils" a substantive operation by using the expression to exclude "oils" which are not apt to be recycled from the scope of the PSO Act. However, it is s 9 of the PSO Act, not the definition of "oils", which is the operative section for determining entitlement to a benefit under the PSO Act. The definition of "oils" in s 6(1) should not be treated as a substantive provision. The function of a statutory definition was considered in Gibb v Commissioner of Taxation (1966) 118 CLR 628; [1966] HCA 74 where Barwick CJ, McTiernan and Taylor JJ said at 635 [10]:
The function of a definition clause in a statute is merely to indicate that when particular words or expressions the subject of definition, are found in the substantive part of the statute under consideration, they are to be understood in the defined sense - or are to be taken to include certain things which, but for the definition, they would not include. Such clauses are, therefore, no more than an aid to the construction of the statute and do not operate in any other way...
A definition only has the function of indicating that, when the word or the expression appears in the substantive provisions of the Act, it is to be understood in the defined sense.
33 Thirdly, whilst it can be said that the products listed in the parentheses have the "common element" identified by the Commissioner, namely they are oils not primarily used for fuel, the evidence showed that some of the products can be and are used as a fuel. Mr Winn gave evidence that lubricants for engines (motor oils) are commonly used as a fuel to power an engine as the lubricant (or motor oil) burns or combusts. Senior counsel for the Commissioner accepted that any of the products in the parenthetical list could be combusted but argued that fact did not tell against their inclusion within the sub-genus of oils which are not used primarily for fuel. It is not enough, however, to identify some common characteristic. The definition of "oils" must be construed in its legislative context and, significantly, unlike in YZ Finance, the context does not support a construction of "petroleum based oils" as an exhaustive definition. The objects of the PSO Act set out in s 3 make it plain that the purpose of the Act is to encourage and reward the recycling of used oil. As by s 9 of the PSO Act only used oils that are recycled qualify for the payment of benefits, an oil that has been combusted in use and is not recyclable does not qualify. It is thus unnecessary to read the "inclusive" product list as exhaustive of the petroleum based products qualifying for benefit entitlements under the Act to give effect to the purpose of the Act. Furthermore, just as some oils which are not used primarily for fuel can be and are used for fuel, some oils which are used primarily for fuel can have other uses, creating waste oil and becoming apt for recycling. Diesel is such an example. The confined reading for which the Commissioner contends is not consistent with, nor promotes, the object and purpose of the Act.
34 Fourthly, another textual reason for concluding that the word "including" is not intended to define the scope of the expression "petroleum based oils" exhaustively is that the expression "petroleum based oils" also applies to synthetic equivalents of goods covered by paragraph (a). Another item which does not fit neatly into the parenthetical list is brake fluid. Mr Winn's evidence was that brake fluids were historically made from a petroleum product, though in recent years have been produced from polyglycol ethers and are considered synthetic. In his experience, even where brake fluid is oil based, it is not generally referred to as an oil. Thus, absent the reference to brake fluids in the parenthetical list, there might otherwise be uncertainty as to whether a synthetic equivalent of brake fluid will come within the expression "petroleum based oils" in circumstances where it is evident from the specific inclusion of brake fluid in the list that brake fluid is intended to be covered by the expression "petroleum based oils".
35 Fifthly, the word "means" is used in other definitions in s 6(1) where it is clear that the definition is intended to be exhaustive: eg the definition of "recycled oil" and "used oil".
36 Sixthly, contrary to the Commissioner's submissions, there is no disconformity or inconsistency between the PSO Act and the Excise Tariff Act and Customs Tariff Act if "petroleum based oils" in s 6(1) of the PSO Act are not confined to "petroleum based oils not primarily used for fuel". Prior to the insertion of Item 15, petroleum products, including lubricants (lubricant based oils), hydraulic oils, and transformer oils were classified to Item 11. The rates of tariff depended on whether the product was for use as fuel or "for other use" or the product was a recycled product on which customs or excise had been paid. With the insertion of Item 15, petroleum products not for use as fuel continued to be classified for tariff purposes but under the new Item 15, which also imposed new rates of tariff on those items, consistent with the intention that benefits payable under the PSO Act be offset by revenue collected through tariffs on petroleum based oils. Significantly, the differentiation between Item 11 (as the relevant Item was at the time the PSO Act was enacted), now Item 10, and Item 15 relates to the use of the petroleum product, not whether the petroleum product is an oil: see Item 11(d) (as it was when the PSO Act was enacted) and Item 10(h).
37 Seventhly, although the PSO Act and the consequential amendments to the Excise Tariff Act and Customs Tariff Act were passed as a package of legislation, they do not constitute a legislative scheme in the sense described in Certain Lloyd's Underwriters v Cross (2012) 248 CLR 378; [2012] HCA 56 ("Cross"). In considering the operation of the Legal Profession Act 1987 (NSW) and the Civil Liability Act 2002 (NSW), Kiefel J stated at 414 [97]-[98]:
For a scheme to be identified, it must involve two statutes not just having a wider common purpose and some connection, but operating together. If the operation of each statute could be said to depend upon the other, there would be a warrant for construing them together in this way. …
It does not follow from the identification of a broader purpose beyond the more immediate objects of each of the two statutes, nor from the limited connection between them, that they were interdependent in any meaningful way. It is necessary to consider each of the statutes and the means by which they are intended to achieve their respective objectives, in order to determine whether they form part of a single scheme. …
The PSO Act, the Excise Tariff Act, and the Customs Tariff Act do not have co-extensive fields of operation and do not deal with the same subject matter but have different purposes and operate independently of each other. The fact that the benefits payable under the PSO Act are funded through excise and customs duties levied on petroleum products does not mean that the Acts operate together and provides no warrant for Item 15 of the tariff classification to be used to control the meaning of "petroleum based oils" as that expression appears in the PSO Act.
38 Also contrary to the Commissioner's submission, it is incorrect to say, as the Commissioner did in his written submissions, that "oils" were never subject to excise until the insertion of Item 15 nor is it correct that diesel is not an "oil" for the purposes of the Excise Tariff Act. As earlier stated, before the insertion of Item 15, the tariff rates on the petroleum products within Item 11 were set by reference to the use of the particular petroleum product, not by reference as to whether the product was an "oil" or not. There is no inconsistency with the Excise Tariff Act if diesel is an "oil" for the purposes of the PSO Act.
39 Eighthly, the Commissioner's reliance on terminology in the Explanatory Memorandum does not advance his case. Statements made in the Explanatory Memorandum cannot displace the text of the statute under construction: Saeed v Minister for Immigration and Citizenship (2010) 241 CLR 252, 265-266; [2010] HCA 23 at [33]-[34]; Cross, 405 [70]. Similarly, the Commissioner's reliance on the Regulation Impact Statement to support his argument that the PSO Act was not intended to apply to recycled diesel cannot displace the provisions of the Act. In the Regulation Impact Statement, the "statement of the problem" was said to be that waste minimisation is a significant issue in Australia and that around 68-71% of virgin lubricant oil was not recovered or reused, and presented a significant and growing environmental hazard. It is unquestionable that the PSO Act was enacted to provide incentives to recycle waste lubricant oil but it is also consistent with the mischief that the Act is intended to remedy that it apply to all waste oil, not just lubricants. There is no evident reason to exclude recycled diesel from the scope of the Act because its primary purpose is for use as a fuel.
40 Ninthly, contrary to the Commissioner's submissions, an harmonious reading of the PSO Act and the Excise Tariff Act does not require that Item 15 be read synonymously with the inclusive list of products enumerated in the expression "petroleum based oils" in the PSO Act. The express exclusion from Item 15 of the Schedule to the Excise Tariff Act of "goods for use as a fuel" does not confirm the genus of the items included in the parenthetical list of "petroleum based oils" in s 6(1) of the PSO Act. The expression "petroleum based oils" in the PSO Act does not contain the words of limitation appearing in Item 15 nor does the PSO Act define the expression "petroleum based oils" in terms of the excise duty classification. In contrast, s 6(2) of the PSO Act does provide that an expression used in the PSO Act that is also used in the Products Grants and Benefits Administration Act 2000 (Cth) "has the same meaning as in that Act, unless the contrary intention appears". There is nothing to suggest that the expression "petroleum based oils" in s 6(1) of the PSO Act was intended to be confined to those products listed in Item 15 of the Schedule to the Excise Tariff Act.
41 Finally, neither a liberal nor a generous reading of the expression "petroleum based oils" in s 6(1) of the PSO Act is required for the recycled diesel in this case to constitute "recycled oil" as that term is defined for the purposes of the PSO Act: cf Commissioner of Taxation v Bargwanna [2009] FCA 620; IW v City of Perth (1997) 191 CLR 1; [1997] HCA 30. Diesel is a petroleum based oil within the ordinary signification of that expression and, for the reasons given, both the text and purpose of the PSO Act support the conclusion that Parliament did not intend the words in parentheses to be exhaustive of the petroleum based oils which are "oils" for the purposes of the PSO Act.
I certify that the preceding forty-one (41) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Davies.