Section 189Migration Act 1958 (Cth)

Detention of unlawful non‑citizens

(1) If an officer knows or reasonably suspects that a person in the migration zone (other than an excised offshore place) is an unlawful non‑citizen, the officer must detain the person.

(2) If an officer reasonably suspects that a person in Australia but outside the migration zone:

(a) is seeking to enter the migration zone (other than an excised offshore place); and

(b) would, if in the migration zone, be an unlawful non‑citizen;

the officer may detain the person.

(3) If an officer knows or reasonably suspects that a person (other than a person referred to in subsection (3A)) in an excised offshore place is an unlawful non‑citizen, the officer must detain the person.

(3A) If an officer knows or reasonably suspects that a person in a protected area:

(a) is a citizen of Papua New Guinea; and

(b) is an unlawful non‑citizen;

the officer may detain the person.

(4) If an officer reasonably suspects that a person in Australia but outside the migration zone:

(a) is seeking to enter an excised offshore place; and

(b) would, if in the migration zone, be an unlawful non‑citizen;

the officer may detain the person.

(5) In subsections (3), (3A) and (4) and any other provisions of this Act that relate to those subsections, officer means an officer within the meaning of section 5, and includes a member of the Australian Defence Force.

Note: See Subdivision B for the Minister’s power to determine that people who are required or permitted by this section to be detained may reside at places not covered by the definition of immigration detention in subsection 5(1).

Sourced from the Federal Register of Legislation at 26 May 2026. For the latest information on Australian Government law please go to https://www.legislation.gov.au. Verify the current text against the official source before relying on it.

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