Public Prosecutor v Mark Kalaivanan s/o Tamilarasan

Mark Kalaivanan s/o Tamilarasan was convicted after trial of aggravated sexual assault by penetration and three related charges arising from 15 July 2017, when he let himself into an unlocked flat, falsely claimed to be a police officer, molested the woman inside and then sexually assaulted her in the toilet. He had serious antecedents, including a 2003 conviction for aggravated rape. The aggravated charge carried a mandatory minimum of 8 years' imprisonment and 12 strokes of the cane.

The High Court sentenced him to preventive detention and 12 strokes. On 9 September 2024 the Court of Appeal raised the preventive detention to the maximum of 20 years, backdated it to his arrest, and let the caning stand. It then emerged that he had been certified medically unfit for caning before the appeal, owing to several conditions including cervical spondylosis. At a further hearing under s 332 of the Criminal Procedure Code, the Prosecution sought six months' imprisonment in place of the caning; the judge remitted the caning in full in Public Prosecutor v Mark Kalaivanan s/o Tamilarasan [2025] SGHC 89. The Prosecution appealed in Criminal Appeal No 21 of 2024.

1. Whether a court can impose imprisonment in place of caning on an offender sentenced to preventive detention
2. Whether such imprisonment can be added if the total would exceed the 20-year maximum for preventive detention
3. Whether additional imprisonment in place of caning was warranted on the facts

Section 332(2)(b) allows imprisonment in place of caning in addition to any other punishment, which read alone could include preventive detention. But that power is expressly subject to any other written law, and s 304(2) provides that preventive detention is imposed in lieu of any sentence of imprisonment. The court held that this covers all imprisonment, including a term substituted for caning, so the substituted term is absorbed into preventive detention. That fitted the distinct protective purpose of preventive detention, its safeguards of a 20-year cap and one term per trial, and the rule that later imprisonment runs concurrently with it. It would also be odd for an offender released on licence to then begin a prison term.

Even if the power existed, it could not push the effective term past 20 years. Section 332(3) permits exceeding the maximum term of imprisonment for an offence, not the maximum period of preventive detention. Unlike s 318(3), which was amended to mention preventive detention, s 332(3) was not. Following Kamis bin Basir v Public Prosecutor [2024] 3 SLR 1713, adding imprisonment on top of maximum preventive detention would undermine the statutory cap.

On the facts, applying Amin bin Abdullah v Public Prosecutor [2017] 5 SLR 904, a sentence should not be enhanced without grounds. Twenty years' preventive detention was already sufficiently retributive and deterrent, and six more months would have little marginal effect. The exemption was on medical grounds, so general deterrence was not lost. Isham bin Kayubi v Public Prosecutor [2021] SGCA 22 involved greater harm, and if the long preventive detention could not deter him, six months more was unlikely to.

The Court of Appeal dismissed the Prosecution's appeal on 10 September 2025, leaving the caning remitted in full with no additional imprisonment. It held that the law does not allow imprisonment in place of caning where preventive detention is ordered, especially where the maximum term has been imposed, and that such imprisonment would not have been necessary in any event.