18Power to obtain information and documents about unlawful non‑citizens

18  Power to obtain information and documents about unlawful non‑citizens  (1) If the Minister has reason to believe that a person (in this subsection called the first person) is capable of giving information which the Minister has reason to believe is, or producing documents (including documents that are copies of other documents) which the Minister has reason to believe are, relevant to ascertaining the identity or whereabouts of another person whom the Minister has reason to believe is an unlawful non‑citizen, the Minister may, by notice in writing served on the first person, require the first person:  (a) to give to the Minister, within the period and in the manner specified in the notice, any such information; or  (b) to produce to the Minister, within the period and in the manner specified in the notice, any such documents; or  (c) to make copies of any such documents and to produce to the Minister, within the period and in the manner specified in the notice, those copies.  (2) A notice under subsection (1) must set out the effects of section 21 of this Act and sections 137.1 and 137.2 of the Criminal Code.