CONCLUSION
38 To the extent that the applicant's case against the respondents depends upon nothing more than its claim that the current Minister is approaching the question of "public interest" in a different manner to his predecessor, it is untenable.
39 The Minister's predecessor may have taken a more benign view of the importation of weapons of this type. If he did, that still cannot form the basis of a conclusion that the Minister's decision in this case was unreasonable. The requirement in s 77EA that the Minister base his decision upon "the public interest" confers upon him a broad and multi-faceted discretion. Reasonable minds are likely to differ as to what that term entails. If the Minister's decision is, ultimately, held to be unreasonable in the Wednesbury sense, it will be because it was wholly irrational and not because his predecessor did not share this Minister's views.
40 It follows that I would be minded to strike out the grounds of review, and the particulars in support thereof, that depend entirely upon reasoning of the type just discussed. I say that in the context of an interlocutory application brought for the sole purpose of obtaining leave to deliver interrogatories aimed at assembling evidence to support a factual finding that leads nowhere in a legal sense. As I will not be hearing this matter when it comes before the Court for final determination, it is sufficient for me to do no more than refuse the application for leave to deliver those interrogatories that relate to the period prior to 6 December 2007 without, at this stage, proceeding to strike out the grounds of review that I regard as untenable.
41 The position regarding the period after 6 December 2007 is more difficult. At a theoretical level, there might be a case in which it could be shown that the Minister has discriminated against the applicant, singling it out for adverse treatment and ignoring the acts of its competitors. Such conduct on the part of the Minister might be amenable to judicial review, if not under the ADJR Act, then certainly pursuant to s 39B.
42 However, the difficulty with that approach in the present case is that the structure of s 77EA provides little scope for its application. There would have to be some basis for believing that the Minister has deliberately set out, in his decision of 6 December 2007, to treat the applicant differently from its competitors.
43 It is possible, in some circumstances, to use later developments as the basis for an inference as to what motivated an earlier decision. In J D Heydon, Cross on Evidence (7th Australian ed, 2004), the learned author observes (at [1170]) in relation to what he characterises as "retrospectant evidence":
"The argument for the reception of this kind of evidence is the converse of that which demonstrates the relevance of prospectant evidence: the subsequent occurrence of an act, state of mind or state of affairs justifies an inference that the act was done, or that the state of mind or affairs previously existed."
44 It is well-established that a person's anterior intention can be proved by his or her subsequent acts. Nonetheless, there are limits to the extent to which this can be done. The evidence of Mr Potter, which is uncontradicted on this point, makes it clear that the Minister does not take a proactive role in relation to his powers under s 77EA. He simply responds to submissions put forward by Customs, as he did in this case. That makes it difficult, if not impossible, to use the fact that importers of firearms of similar appearance to the Heckler and Koch SL 8-R have not had their weapons detained as the basis for a challenge to the Minister's decision.
45 Once again, I do not think it necessary to formally order that the grounds of review, and the particulars in support thereof, that rely on this mode of reasoning be struck out. That does not mean that I regard them as necessarily having reasonable prospects of success. Indeed, it does not mean that I regard them as necessarily being even arguable. It is sufficient for present purposes to say that leave should not be granted to deliver any interrogatories that relate to these grounds.
46 To grant leave to interrogate in the circumstances presented here would be to encourage not merely "fishing" but full-scale "trawling". It is well-established in relation to discovery that a party who can demonstrate nothing to support an allegation will not be granted access to the documents of the opposing party in the hope of discovering some such support. See, for example, WA Pines Pty Ltd v Bannerman. This principle applies with equal force to those seeking relief under the ADJR Act: Minister for Immigration and Multicultural and Indigenous Affairs v Wong at [29]-[32]. It is not open to a party merely to allege that a decision was made without any proper basis and then seek to use the compulsory process of the Court to attempt to find out if that allegation has any foundation. Before discovery can be ordered, there must be some evidence that can support an arguable case for review, proof of which is likely to be aided by requiring production of relevant documents.
47 The same approach should be taken to the grant of leave to deliver interrogatories.
48 It should not be thought that I reject absolutely the use of additional evidence on judicial review. While generally the state of mind of the decision maker would be irrelevant in judicial review, there are cases which warrant the reception of such evidence: see, for example, Percerep v Minister for Immigration and Multicultural Affairs (1998) 86 FCR 483 and McCormack v Deputy Commissioner of Taxation Large Business & International [2001] FCA 1700 at [38]. For example, allegations of actual bias may require evidence relating to extraneous matters going far beyond the material before the decision maker. Claims of improper purpose typically present evidentiary difficulties. The Court must determine, in cases of that type, whether a stated purpose was in fact the real purpose. Such claims often fail for lack of sufficient evidence. On occasion, however, documents obtained on discovery and answers to interrogatories can provide evidence of motive or purpose and, accordingly, may be of relevance. See, for example, Minister for Immigration and Multicultural and Indigenous Affairs v Wong at [26].
49 Similarly, grounds of review that involve allegations of fraud or dishonesty, or even seriously improper behaviour, may justify the making of such orders. For a time, there developed a body of case law in this country involving challenges to the validity of search warrants, essentially on the basis that they had been improperly obtained. The principle seems to have been that a warrant obtained by a half-truth should be set aside. See generally the authorities collected and discussed by Aronson, Dyer and Groves "Judicial Review of Administrative Action" (3rd ed, 2004, at 302, fn 339). In some of these cases, far-ranging discovery was ordered and informative documents obtained. Interestingly, however, attempts to deliver interrogatories were generally unsuccessful: see, for example, Grofam Pty Ltd v Macauley (1993) 43 FCR 404, where leave to serve interrogatories on a magistrate who had issued a search warrant was refused.
50 The only grounds of review that could even conceivably support the grant of leave to deliver interrogatories in this case are those alleging discrimination on the part of this Minister when he decided to have the applicant's weapons detained, based upon his later treatment of its competitors. These are ground 7(d) in support of the ADJR Act application and ground 8(e) in support of the s 39B(1A)(c) application. However, as discussed above, those grounds are largely speculative. They do not warrant the grant of leave to interrogate.
51 It follows that I need not determine whether, as the respondents contend, it would be unduly burdensome for them to be required to answer the proposed interrogatories. The applicant has failed to establish any adequate basis for their delivery. The grounds of review to which they are directed are untenable.
I certify that the preceding fifty-one (51) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Weinberg.