Consideration
34 This matter involves executive detention pursuant to s 189(1) of the Act. The lawfulness of a person's detention under s 189(1) depends on whether an officer holds reasonable suspicion or knowledge that the detained person is an unlawful non-citizen. Thus, an applicant for a writ of habeas corpus seeking to challenge the lawfulness of his or her current detention under s 189(1) must show some basis on which a court could conclude that he or she is not an unlawful non-citizen or the detaining officer did not reasonably suspect that he or she is an unlawful non-citizen. That evidentiary burden relates to the circumstances of the exercise of the statutory power to detain and its nature. Once an applicant's evidence puts one or more of those questions in issue, the onus shifts to the respondent to establish that the current detention is lawful.
35 What constitute reasonable grounds for suspecting a person to be an unlawful non-citizen for the purposes of s 189(1) of the Act must be judged against what the detainer knows or reasonably suspects at the relevant time (ie. at the time the detention was effected or is sought to be maintained): Thoms v Commonwealth (2022) 96 ALJR 635 at 641 [21] per Kiefel CJ, Keane and Gleeson JJ.
36 It may be observed immediately that before the primary judge the appellant failed to discharge his evidentiary onus. The primary judge found as much in his reasons at [11], to which we have referred to above, and against which there is no challenge on appeal.
37 The appellant submitted further that there is no distinction between the requirements of an application for habeas corpus and a claim for false imprisonment. The appellant referred to the observations of Mortimer J in McHugh 283 FCR at 665 [282] where her Honour said:
Thus, on the present state of authority there is no distinction to be drawn between the burden of proof in false imprisonment and any other claim for release based on unlawful detention, whether described as habeas corpus, or as orders in the nature of habeas corpus, or as mandatory injunctions. In terms of the burden of proof no distinction is maintained and in each situation the burden is seen as lying on the detainer. While not all judicial minds may have approached the matter seeing them as equivalent (eg see Black CJ's reasons in Vadarlis at [70]), the present state of authority is clear …
38 We have dealt with that passage of her Honour's judgment above. It may be accepted that the tort of false imprisonment has two elements, first, the fact of imprisonment and, second, upon that element being satisfied by the applicant for relief, the onus shifts to the respondent to show lawful authority to justify that imprisonment: Lewis v Australian Capital Territory (2020) 271 CLR 192 at 206 [24] per Gageler J; Taylor 222 CLR at 650-651 [140] per Kirby J. As to the latter case, although Kirby J was in dissent, there is no issue concerning this point.
39 Three things should be observed about the appellant's submission. First, it fails to give due recognition to the difference in the nature of proceedings for the issue of a writ of habeas corpus (or an order in the nature of habeas corpus) and proceedings for damages for the tort of false imprisonment. In each case, the applicant bears an onus of proof that must be discharged before the detainer is called upon to prove the lawfulness of the detention (if it can do so). While the onus on the detainer is the same in each proceeding, the onus on the applicant is different. In the case of habeas corpus, the applicant must demonstrate that, at the time of applying for the writ, there is a "case fit to be considered". In the case of false imprisonment, the applicant must demonstrate only the fact of his or her imprisonment.
40 Secondly, and linked to the first, proving the fact of imprisonment is not the same as proving in habeas corpus proceedings that there is a "case fit to be considered" so as to oblige the detainer to demonstrate the lawfulness of the detention at the time of the application and or hearing. Thus, although in the cited passage Mortimer J identified that the burden of proof was the same for both false imprisonment and any other claim for release based on unlawful detention whether described as habeas corpus or otherwise, her Honour was not disagreeing with the long line of authority that in an application for a writ of habeas corpus (or an order in the nature of habeas corpus) it is the applicant who must first discharge the evidentiary burden that, at the time of the hearing, to use her Honour's words, there is a "case fit to be considered" by the court that the applicant's detention is unlawful. In any event, her Honour's observations about this issue were obiter dicta in respect of causes of action other than that for false imprisonment.
41 Thirdly, the submission fails to recognise the two causes of action have different timing requirements in relation to the evidentiary onus on each of the applicant and detainer. The two causes of action, although having the same ultimate burden of proof for the detainer, differ in the times at which that burden is called upon to be satisfied. As the authorities to which we have referred make clear, an applicant for a writ of habeas corpus or an order in the nature of habeas corpus must satisfy the evidentiary burden, at the time the application is heard, that there is a "case fit to be considered" before the detainer is called upon to discharge its substantive burden.
42 In contrast, in an action for false imprisonment, after the applicant has proved the fact of imprisonment and the duration of that imprisonment, the onus shifts to the detainer to prove the lawfulness of the imprisonment or detention throughout the period of the imprisonment or detention. That is not the same issue that arises on an application for a writ of habeas corpus or ascertaining if imprisonment or detention is lawful at a particular point in time, namely, the hearing.
43 The appellant's submission that his initial detention in 2013 was unlawful not only was unsupported by his affidavit filed in support of the application but was also irrelevant to the issue to be considered, namely, whether there was a sufficient basis to consider whether his detention was unlawful at the time of the hearing and, if so, whether the respondent had shown that it was in fact lawful.
44 That is not to say that the circumstances in which a person is detained can never be relevant to the question of whether any current detention is lawful. For example, a person arrested and taken into custody in reliance on a defective warrant of arrest or other instrument purporting to authorise his or her detention may result in unlawful imprisonment because the invalidity of the warrant or other instrument denies the lawfulness of any such detention. Likewise, if a person is taken into immigration detention without any officer forming the state of mind required by s 189(1), the detention is unlawful unless and until an officer forms such a state of mind: Fernando 200 FCR at 19 [84], [87], 20 [90]-[91] per Gray, Rares and Tracey JJ.
45 Here, the primary judge made an unchallenged finding that, at the time of the hearing, an officer knew or reasonably suspected that the appellant was an unlawful non-citizen as required by s 189(1) of the Act so that his claim for the issue of a writ of habeas corpus (or an order in the nature of such a writ) failed. Moreover, as the appellant acknowledged in his submissions in the appeal, he "made no claim that his detention was unlawful, and was not required to do so".
46 In addition, the appellant led no evidence to suggest that, at the time of the hearing, he did not have the status of an unlawful non-citizen or that an officer did not have reasonable grounds to suspect that he was.
47 As we have explained, the appellant had an evidentiary onus to show an arguable basis that, at the time of the hearing, his detention was unlawful. However, since the primary judge found as a fact that, at the hearing, his detention under s 189(1) was lawful, he was correct to dismiss the appellant's claim for the issue of the writ.