6.2 Relevant principles
33 In Minister for Immigration and Border Protection v Eden [2016] FCAFC 28; (2016) 240 FCR 158 (Eden) the Full Court (Allsop CJ, Griffiths, and Wigney JJ) identified, as is the case here, that the Minister's power to cancel a visa is only enlivened if the Minister reasonably suspects that the visa-holder does not pass the character test (as defined in s 501(6) of the Act) and the visa-holder does not satisfy the Minister that he or she satisfies the character test (Eden at [15]). There is no question that the discretion was enlivened in the present case. Once enlivened, the court in Eden identified that some of the relevant principles concerning legal unreasonableness are:
58 First, the concept of legal unreasonableness concerns the lawful exercise of power. Legal reasonableness, or an absence of legal unreasonableness, is an essential element in the lawfulness of decision-making: Li at 350[26] and 351[29] (French CJ), 362[63] (Hayne, Kiefel and Bell JJ) and 370[88] (Gageler J); Singh at 445[43]; Stretton at [4] (Allsop CJ) and [53] (Griffiths J).
59 Second, the Court's task in determining whether a decision is vitiated for legal unreasonableness is strictly supervisory (Li at 363[66]). It does not involve the Court reviewing the merits of the decision under the guise of an evaluation of the decision's reasonableness, or the Court substituting its own view as to how the decision should be exercised for that of the decision maker: Li at 363[66] (Hayne, Kiefel and Bell JJ); Stretton at [12] (Allsop CJ) and [58] (Griffiths J); see also M64/2015 v Minister for Immigration and Border Protection [2015] HCA 50; (2015) 90 ALJR 197 at 203[23]. Nor does it involve the Court remaking the decision according to its own view of reasonableness: Stretton at [8] (Allsop CJ).
60 Third, there are two contexts in which the concept of legal unreasonableness may be employed. The first involves a conclusion after the identification of a recognised species of jurisdictional error in the decision making process, such as failing to have regard to a mandatory consideration, or having regard to an irrelevant consideration. The second involves an "outcome focused" conclusion without any specific jurisdictional error being identified: Li at 350[27]-351[28] (French CJ), [72] (Hayne, Kiefel and Bell JJ); Singh at [44]; Stretton at [6] (Allsop CJ).
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62 Fourth, in assessing whether a particular outcome is unreasonable, it is necessary to bear in mind that within the boundaries of power there is an area of "decisional freedom" within which a decision-maker has a genuinely free discretion: Li at 351[29] (French CJ), 363[66] (Hayne, Kiefel and Bell JJ). Within that area, reasonable minds might differ as to the correct decision or outcome, but any decision or outcome within that area is within the bounds of legal reasonableness: Li at 363[66] (Hayne, Kiefel and Bell JJ); Stretton at [7] (Allsop CJ). Such a decision falls within the range of possible lawful outcomes of the exercise of the power: Li at 375[105] (Gageler J); Stretton at [11] (Allsop CJ).
63 Fifth, in order to identify or define the width and boundaries of this area of decisional freedom and the bounds of legal reasonableness, it is necessary to construe the relevant statute: Li at 349[24] (French CJ), 363[67]-364[67] (Hayne, Kiefel and Bell JJ); Stretton at [55] and [62] (Griffiths J). The task of determining whether a decision is legally reasonable or unreasonable involves the evaluation of the nature and quality of the decision by reference to the subject matter, scope and purpose of the relevant statutory power, together with the attendant principles and values of the common law concerning reasonableness in decision-making: Stretton at [7] and [11] (Allsop CJ). The evaluation is also likely to be fact dependant and to require careful attention to the evidence: Singh at 445[42].
64 Sixth, where reasons for the decision are available, the reasons are likely to provide the focus for the evaluation of whether the decision is legally unreasonable: Singh at 446[45]-447[47]. Where the reasons provide an evident and intelligible justification for the decision, it is unlikely that the decision could be considered to be legally unreasonable: Singh at [47]. However, an inference or conclusion of legal unreasonableness may be drawn even if no error in the reasons can be identified. In such a case, the court may not be able to comprehend from the reasons how the decision was arrived at, or the justification in the reasons may not be sufficient to outweigh the inference that the decision is otherwise outside the bounds of legal reasonableness or outside the range of possible lawful outcomes: Li at 367[76] (Hayne, Kiefel and Bell JJ); Stretton at [13] (Allsop CJ).
65 Seventh, and perhaps most importantly, the evaluation of whether a decision is legally unreasonable should not be approached by way of the application of particular definitions, fixed formulae, categorisations or verbal descriptions. The concept of legal unreasonableness is not amenable to rigidly defined categorisation or precise textural formulary: Stretton at [2] and [10] (Allsop CJ) and [62] (Griffiths J). That said, the consideration of whether a decision is legally unreasonable may be assisted by reference to descriptive expressions that have been used in previous cases to describe the particular qualities of decisions that exceed the limits and boundaries of statutory power. A number of those cases, and the descriptive expressions used in them, are referred to in Li and in the judgment of Allsop CJ in Stretton (at [5]). The expressions that have been utilised include decisions which are "plainly unjust", "arbitrary", "capricious", "irrational", "lacking in evident or intelligible justification", and "obviously disproportionate". It must be emphasised again, however, that the task is not an a priori definitional exercise. Nor does it involve a "checklist" exercise: Singh at 445[42]. Rather, it involves the Court evaluating the decision with a view to determining whether, having regard to the terms, scope and purpose of the relevant statutory power, the decision possesses one or more of those sorts of qualities such that it falls outside the range of lawful outcomes.
34 In the fifth point above the Full Court emphasises the need evaluate the nature and quality of the decision by reference to the subject matter, scope and purpose of the relevant statutory power, together with the attendant principles and values of the common law concerning reasonableness in decision-making. In Eden, as in the present case, s 501(2) was under consideration. At [19] that Court observed that there are a number of indicators that suggest that the Minister's discretion under s 501(2) is, and is intended to be, broad. That is a relevant consideration in assessing whether a decision under s 501(2) of the Act is unreasonable in a legal sense. The indicators include, but are not necessarily limited to, the following: the absence of an express list of considerations to be taken into account; the broad statement of the object of the Act in s 4(1) as being to "regulate, in the national interest, the coming into and presence in, Australia of non-citizens"; the fact that the discretion is conferred upon the Minister who holds political office and is accountable to Parliament; the fact that a decision under s 501(2) which is made by the Minister personally is not subject to merits review; and the fact that the Minister is obliged by s 501G(1)(e) of the Act to provide a written statement of reasons. See also; BCR16 v Minister for Immigration and Border Protection [2017] FCAFC 96 at [24] (Bromberg, Davies and Mortimer JJ); Poroa v Minister for Immigration and Border Protection [2017] FCA 826; (2017) 252 FCR 505 at [10] (Perry J).