(b) to give evidence in proceedings or to give assistance in relation to an investigation pursuant to a request made by or on behalf of the Attorney-General, not being a request in terms of section fourteen, for assistance in a criminal matter; the person, subject to subsection (2), shall not be detained, prosecuted or punished in Zimbabwe for any offence that is alleged to have been committed, or that was committed, before the person’s departure from the foreign country pursuant to the request, or be subjected to any civil suit in respect of any act or omission of the person that is alleged to have occurred before the person’s departure from the foreign country pursuant to the request, or be required to give evidence in any proceedings in Zimbabwe other than the proceedings to which the request relates. (2) Subsection (1) shall cease to apply to a person— (a) once the person has left Zimbabwe; or (b) where the person has had the opportunity to leave Zimbabwe but has remained in Zimbabwe otherwise than for— (i) the purpose to which the request related; or (ii) the purpose of giving evidence in proceedings in Zimbabwe certified by the Attorney-General, in writing, to be proceedings in which it is desirable that the person give evidence; or (iii) the purpose of giving assistance in relation to an investigation in Zimbabwe certified by the Attorney-General, in writing, to be an investigation in relation to which it is desirable that the person give assistance. (3) A certificate given by the Attorney-General for the purposes of subparagraph (ii) or (iii) of paragraph (b) of subsection (2) shall have effect from the day specified in the certificate. 18 Status of person prosecuted for offence committed after departure from foreign country (1) Where a person has come to Zimbabwe pursuant to a request to a foreign country in terms of section fourteen, the person shall be taken, for the purposes of this Act to be in Zimbabwe pursuant to the request during any period which the person remains in Zimbabwe for the purpose of being tried for a Zimbabwean criminal offence that the person is alleged to have committed after the person’s arrival in Zimbabwe from the foreign country. (2) Without limiting the generality of subsection (1), the person shall be kept in such custody as the AttorneyGeneral directs in terms of section sixteen. 19 Limitation on use of evidence by certain persons Where— (a) a person is in Zimbabwe— (i) pursuant to a request in terms of section fourteen, (ii) to give evidence in proceedings, or to give assistance in relation to an investigation pursuant to a request made by or on behalf of the Attorney-General, not being a request in terms of section fourteen, for assistance in criminal matters; and (b) the person has given evidence in the proceedings to which the request related or in proceedings certified by the Attorney-General in terms of subparagraph (ii) of paragraph (b) of subsection (2) of section seventeen in relation to that person; that evidence shall not be admitted or otherwise used in any prosecution of the person for an offence against the law of Zimbabwe, other than the offence of perjury in relation to the giving of that evidence. 20 Conditions of imprisonment The provisions of the Prisons Act [Chapter 7:11] relating to— (a) the conditions of imprisonment of persons convicted of offences; and (b) the treatment of any such persons during imprisonment; and (c) the transfer of any such persons from prison to prison; shall apply, mutatis mutandis, in relation to a person who is in Zimbabwe pursuant to a request in terms of section fourteen and who has been committed to a prison in accordance with a direction of the Attorney-General in terms of this Act. 21 Release of certain persons upon request by foreign country Where— (a) a person is being held in custody in accordance with a direction of the Attorney-General in terms of section sixteen; and (b) the foreign country from which the person has been brought requests the release of the person from custody; the Attorney-General shall direct that the person be released from custody.