Section 4AA of the Migration Act 1958 (Cth) does not give rise to an independent and actionable statutory duty, but it is not merely aspirational — decisions made under the Act must be made in accordance with the affirmed principle that minors shall only be detained as a measure of last resort. The existence of the Minister's non-compellable, non-reviewable discretionary power (s 197AE) and the privative clause (s 474) are key indicators of a contrary intention to the creation of a private right of action.
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