s 42 Information: embarking passengers
(1) Schedule 2 to the Immigration Act 1971 (c. 77) (control on entry, &c.) shall be amended as follows. (2) In paragraph 3(1) for the words from “and if he is not” to the end substitute— and, if he is not a British citizen, for the purpose of establishing— (a) his identity; (b) whether he entered the United Kingdom lawfully; (c) whether he has complied with any conditions of leave to enter or remain in the United Kingdom; (d) whether his return to the United Kingdom is prohibited or restricted. (1A) An immigration officer who examines a person under sub-paragraph (1) may require him, by notice in writing, to submit to further examination for a purpose specified in that sub-paragraph. (3) After paragraph 16(1A) insert— (1B) A person who has been required to submit to further examination under paragraph 3(1A) may be detained under the authority of an immigration officer, for a period not exceeding 12 hours, pending the completion of the examination. (4) In paragraph 21(1) after “16” insert “ (1), (1A) or (2) ” .