20 In Chugg v Pacific Dunlop Ltd (1990) 170 CLR 249, involving a prosecution under the Occupational Health and Safety Act 2004 (Vic), the relevant Act defined "practicable" to include the cost of implementation of measures. Dawson, Toohey and Gaudron JJ (Brennan J generally agreed and Deane J agreeing) held at 261:
One consideration tells against overmuch significance being given to the relative knowledge of an employer and an informant. The questions of safety and practicability, in many cases, raise issues of common sense rather than special knowledge: see Neill v NSW Fresh Food & Ice Co Pty Ltd (1963) 108 CLR 362, per Taylor and Owen JJ at 368. See also Australian Oil Refining Co Ltd v Bourne at 193-194. In some cases the mere identification of the cause of a perceptible risk may, as a matter of common sense, also constitute identification of a means of removing that risk, thereby giving rise to a strong inference that an employer failed to provide "so far as is practicable" a safe workplace. In other cases the same inference will arise from the identification of some method which would remove or mitigate a perceptible risk or hazard. And, in such cases, that inference might well be further strengthened by the failure of an employer to call evidence as to matters, such as cost and suitability, peculiarly within his knowledge: see Jones v Dunkel (1959) 101 CLR 298.
A consideration of the relative knowledge of an employer and an informant does not, in our view, provide an indication that the defendant bears the onus of proof on the issue of practicability in a prosecution for an offence under s 21 of the Act. In particular, the subject matter of practicability is not necessarily new or different from the subject matter of a rule requiring that a workplace be safe. So much is evident from par (a) of the definition of "practicable", which looks to "the severity of the hazard or risk in question". And, although matters pertaining to cost and suitability of the means of avoiding a risk or hazard may be peculiarly within the knowledge of the defendant, the question of practicability does not depend on facts peculiarly within the knowledge of a defendant in the same way as does a question whether a proscribed act was done, in the terms used in Edwards, "in specified circumstances or by persons of specified classes or with specified qualifications or with the licence or permission of specified authorities". That is because questions of cost and suitability are but aspects of the overall question of practicability. And they are aspects upon which, in a good many cases, the practical evidentiary burden will, in any event, fall on a defendant for, as earlier indicated, evidence as to the nature of the risk, the cause of the risk or means by which the risk may be avoided will often be all that is necessary to ground an inference that practicable means of avoiding the risk were not taken.
21 The approach in Chugg supports the Prosecutor's approach to what "practicable" means. The Defendant's submission that it requires the Prosecutor to stand in the Defendant's shoes and determine against all the criteria specified in the request for particulars, including financial, that a particular approach is practicable is not maintainable. The Prosecutor's solicitor's letter of 11 September 2008 defined available "practicable means" and "as may be necessary" for the purposes of that element of the offence. The Defendant knows the case and evidence it must meet.