Plaintiffs M69-2007 v Minister for Immigration & Citizenship & Anor

In *Plaintiffs M69-2007 v Minister for Immigration & Citizenship & Anor*, the High Court of Australia considered the lawfulness of the detention of asylum seekers who had arrived in Australia by boat. The plaintiffs, identified only by a pseudonym, were detained pursuant to s 189(1) of the *Migration Act 1958* (Cth) upon their arrival in Australian waters. They sought declarations that their detention was unlawful and damages for false imprisonment. The Minister for Immigration and Citizenship and the Commonwealth of Australia were the respondents.

The central legal issue before the High Court was whether the executive government, through the Minister, had the constitutional power to detain non-citizens who arrived in Australia unlawfully, in circumstances where the *Migration Act* mandated such detention. Specifically, the Court had to determine if the power to detain, as exercised under the *Migration Act*, was supported by the executive power of the Commonwealth under s 61 of the *Constitution*, or if it infringed upon the implied constitutional prohibition against the executive government detaining individuals without lawful authority.

Hayne J, delivering the sole judgment, held that the detention of the plaintiffs was lawful. His Honour reasoned that the *Migration Act* validly conferred the power to detain non-citizens who arrived in Australia unlawfully. This legislative power was not beyond the constitutional reach of the Parliament. The executive power of the Commonwealth, as established by s 61 of the *Constitution*, extended to the implementation of laws enacted by Parliament, including those relating to immigration and border control. Therefore, the detention mandated by the *Migration Act* was a lawful exercise of executive power in accordance with parliamentary will, and did not offend any constitutional principle.

The High Court dismissed the plaintiffs' application for declarations and damages.