Prisoners of unsound mind
43.—(1)  Whenever a prisoner undergoing a sentence of imprisonment appears to the Minister on the certificate of a registered medical practitioner to be of unsound mind, the Minister may, by order in writing, setting forth the grounds of belief that the prisoner is of unsound mind, direct his removal from any prison to any mental hospital or other fit place of safe custody within Singapore, there to be kept and treated as the Minister directs —
(a)until the expiration of the term of imprisonment ordered by the sentence; or
(b)if it is certified by a medical officer that it is necessary for the safety of the prisoner or of others that he should be detained under medical care and treatment, until he is discharged according to law.
(2)  When it appears to the Minister on the certificate of a registered medical practitioner that such prisoner has again become of sound mind, the Minister shall, by an order in writing, return him to the prison from where he was removed if his term of imprisonment has not expired, but if the term has expired, shall direct him to be discharged.
(3)  Section 40 of the Mental Disorders and Treatment Act (Cap. 178) shall apply to every person confined in a mental hospital under this section after the expiration of the term of imprisonment to which he has been sentenced, and the time during which he is so confined shall be reckoned as part of such term.
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