DBE17 (by his litigation guardian Marie Theresa Arthur)

The plaintiff, DBE17, by his litigation guardian Marie Theresa Arthur, brought proceedings against the Commonwealth of Australia. The dispute concerned allegations of unlawful detention. The matter came before the High Court of Australia.

The primary legal issues before the Court were whether it had a discretion regarding which court to remit the matter to, and if so, which court should be preferred. A further consideration raised by the Court was whether section 486B of the *Migration Act 1958* (Cth) might preclude the action. The Court also had to determine whether the proceedings related to a "migration decision" for the purposes of section 476B of the *Migration Act*, which dictates that such matters must be remitted to the Federal Circuit Court.

The plaintiff argued that the proceedings were founded in tort for false imprisonment and did not challenge any migration decision. The claims alleged detention for periods where the stated purposes for detention, namely processing a visa application or determining removal to an offshore processing facility, were not being pursued. The plaintiff contended that the detention became unlawful when the Commonwealth acted too slowly in pursuing these purposes, rather than challenging the validity of any visa application or decision. The plaintiff submitted that the references to migration decisions in the pleadings were merely factual markers to delineate periods of detention, and that the core subject matter was the detention itself, not a migration decision. The Court considered the definitions of "migration decision" and "privative clause decision" within the *Migration Act* and the operational nature of section 189, which mandates detention of unlawful non-citizens.