Could reasonably be expected to
The phrase ‘could reasonably be expected to’ appears in various provisions of the RTI and IP Acts and is the relevant test to be applied when assessing various grounds for non-disclosure. This is an objective test. This means it is ‘approached from the view point of the reasonable decision-maker’.1
In Attorney-General’s Department v Cockcroft (Cockcroft),2 Bowen CJ and Beaumont J considered the phrase 'could reasonably be expected to' which appeared in section 43(1)(c)(ii) of the Commonwealth FOI Act, stating:
In our opinion, in the present context, the words 'could reasonably be expected to prejudice the future supply of information' were intended to receive their ordinary meaning. That is to say, they require a judgment to be made by the decision-maker as to whether it is reasonable, as distinct from something that is irrational, absurd or ridiculous ... It is undesirable to attempt any paraphrase of these words. In particular, it is undesirable to consider the operation of the provision in terms of probabilities or possibilities or the like. To construe s43(1)(c)(ii) as depending in its application upon the occurrence of certain events in terms of any specific degree of likelihood or probability is, in our view, to place an unwarranted gloss upon the relatively plain words of the Act. It is preferable to confine the inquiry to whether the expectation claimed was reasonably based.
Accordingly, the words are to be given their ordinary meaning3 and the relevant expectation must be reasonably based and not irrational, absurd or ridiculous.4 Though it is important to note Hayne J’s cautionary comment in McKinnon v Secretary, Department of Treasury5 that:
"... when their Honours said, as they did [in Cockcroft], that the words required a "judgment to be made by the decision-maker as to whether it is reasonable, as distinct from something that is irrational, absurd or ridiculous," to expect certain consequences, they are not to be understood as having used the latter expression as a paraphrase of the former. Rather, they are to be understood, and have since been understood, as doing no more than drawing an emphatic comparison. To do more would have been, as their Honours correctly said, "to place an unwarranted gloss upon the relatively plain words of the Act".
An expectation of an occurrence that is merely a possibility (ie speculative, conjectural or hypothetical) is unreasonable.6 At the same time, it is not necessary for the decision maker to be satisfied on the balance of probabilities that the expectation will crystalize.7 As explained in Neary and State Rail Authority:8
… There must be more than a mere risk. While the key word used in the relevant provision - `expect' - carries a firmer connotation than words such as `anticipates', it is not necessary that the level of risk be such that it be assessed as more probable than not. Nor is it necessary for the administrator to apply a balance of probabilities calculus similar to that used to set the burden of proof in litigation. All relevant factors, including public interest considerations, should be taken into account. The extent and nature of the effect will be relevant, and often decisive. It is necessary to assess what is reasonable in the circumstances.
Importantly, the expectation must arise as a result of disclosure, rather than from other circumstances.9
 Leech v Sydney Water Corporation  NSWADT 298 citing Neary v State Rail Authority  NSWADT 107.
 (1986) 64 ALR 97 at 106.
 Searle Australia Pty Ltd v PIAC (1992) 108 ALR 163 at 175.
 Cockroft at page 106.
 (2006) 229 ALR 187 at 204.
 Murphy and Treasury Department (1995) 2 QAR 744 at paragraph 44, citing Re B and Brisbane North Regional Heath Authority (1994) 1 QAR 279 at paragraph 160.
 Cockroft at page 106.
  NSWADT 107 at paragraph 35.
 Murphy and Treasury Department (1995) 2 QAR 744 at paragraph 54.