Case Details
- Citation: [2025] SGCA 44
- Title: Zin Mar New v Public Prosecutor
- Court: Court of Appeal of the Republic of Singapore
- Date of decision: 18 September 2025
- Procedural dates: Hearing on 14 May 2025; further hearing on 26 August 2025
- Case type: Criminal Appeal
- Criminal Appeal No: 10 of 2023
- Underlying criminal case: Criminal Case No 60 of 2021
- Appellant/Accused: Zin Mar New (foreign domestic worker)
- Respondent/Prosecution: Public Prosecutor
- Judges: Sundaresh Menon CJ, Tay Yong Kwang JCA and See Kee Oon JAD
- Legal areas: Criminal Law — Defences; Criminal Law — Offences, Criminal Procedure and Sentencing — Sentencing
- Defences in issue: Diminished responsibility (Exception 7 to s 300 of the Penal Code); Grave and sudden provocation (Exception 1 to s 300 of the Penal Code)
- Offences in issue: Murder (s 300(c) read with s 302(2) of the Penal Code); Culpable homicide not amounting to murder (s 304(a) of the Penal Code)
- Sentencing issue: Whether life imprisonment should be imposed and, if conviction altered, the appropriate term
- Judgment length: 49 pages; 13,810 words
- Statutes referenced: Penal Code (Cap 224, 2008 Rev Ed) — ss 300, 302, 304(a); Exceptions 1 and 7
- Cases cited (as provided): [2004] SGHC 244; [2023] SGHC 146; [2025] SGCA 44
Summary
In Zin Mar New v Public Prosecutor ([2025] SGCA 44), the Court of Appeal considered how partial defences under the Penal Code should be applied to a murder charge where the accused relied at trial solely on diminished responsibility. The appellant, a foreign domestic worker, was convicted of murder for stabbing her employer’s mother-in-law multiple times. She argued that she suffered from a mental disorder that substantially impaired her mental responsibility at the time of the offence. The trial judge rejected the defence and convicted her of murder, imposing life imprisonment on the basis that she was likely under 18 at the time of the offence.
On appeal, the Court of Appeal allowed the appeal against conviction. Although the appellant had not pleaded grave and sudden provocation at trial, the appellate court held that sufficient evidence had been led to enable her to avail herself of the partial defence under Exception 1 to s 300 of the Penal Code. The court then conducted a further hearing, convicted her on an amended charge of culpable homicide not amounting to murder under s 304(a), and reduced her sentence from life imprisonment to 17 years’ imprisonment.
What Were the Facts of This Case?
The appellant, Ms Zin Mar New, is a Burmese national who arrived in Singapore on 5 January 2018 to work as a foreign domestic worker. In the course of her entry and employment arrangements, she falsely declared her age as 23. Later bone-age testing indicated that she was closer to 17 years old as at the date of the offence, which occurred on 25 June 2018.
From 10 May 2018, the appellant worked in the household of “Mr S”. The household comprised Mr S, his wife (“Mrs S”), and their two daughters (“D1” and “D2”). The deceased, Mdm M (“the Deceased”), was Mr S’s mother-in-law. She arrived in Singapore from India on 26 May 2018 for a month-long stay at the family’s residence (the “Unit”).
On 25 June 2018, Mr S, Mrs S, and the children left the Unit by 11.27am. The appellant remained at home with the Deceased. Between 11.27am and 12.17pm, the appellant brought a knife from the kitchen to the living room where the Deceased was watching television on a sofa. She stabbed the Deceased multiple times until the Deceased stopped moving. After the stabbing, the appellant went to a bedroom, broke into a locked cupboard, and retrieved personal effects and some money belonging to her. She washed the knife and left it in the kitchen, where it was later recovered by the police.
At about 12.17pm, the appellant left the Unit after changing her clothes and gathering some personal belongings. She went to her employment agency to request her passport, but left when she heard the agency staff were about to call her employers. She then moved around various locations in Singapore before returning to the agency at about 5.30pm. She was arrested shortly thereafter at around 5.55pm. An autopsy was performed the same day by Clinical Professor Gilbert Lau. The cause of death was certified as “multiple stab wounds”, and the expert opined that three of the 26 stab wounds would, in the ordinary course of nature, have sufficed to cause death.
What Were the Key Legal Issues?
The first major issue was whether the appellant could establish diminished responsibility under Exception 7 to s 300 of the Penal Code. This defence requires proof of (i) an abnormality of mind; (ii) aetiological connection between the abnormality and a mental disorder; and (iii) substantial impairment of mental responsibility at the time of the offence. The appellant had relied solely on this defence at trial, supported by psychiatric evidence that she was in a dissociative state and unable to control her actions.
The second issue concerned whether the appellant could, for the first time on appeal, rely on the alternative partial defence of grave and sudden provocation under Exception 1 to s 300 of the Penal Code. The Court of Appeal had to determine whether, notwithstanding the defence not being advanced at trial, the evidence led was sufficient to satisfy both the subjective and objective components of Exception 1. This included examining the appellant’s contemporaneous accounts and the circumstances surrounding the offence, including the Deceased’s alleged threat immediately before the stabbing.
Finally, once the conviction was altered, the court had to address sentencing. In particular, it had to determine the appropriate sentence for culpable homicide not amounting to murder under s 304(a), taking into account the appellant’s likely minority at the time of the offence and the sentencing principles applicable to partial defences.
How Did the Court Analyse the Issues?
The Court of Appeal began by setting out the legal framework for diminished responsibility under Exception 7. While the extract provided focuses on the requirements, the court’s analysis necessarily turned on whether the psychiatric evidence established the three elements: abnormality of mind; aetiology (ie, that the abnormality was induced by a mental disorder); and substantial impairment of mental responsibility. The appellant’s case at trial depended heavily on expert testimony from Dr Tommy Tan Kay Seng, who diagnosed “mixed anxiety and depressive reaction” / “adjustment disorder with mixed anxiety and depressed mood” (collectively referred to as the “AD Diagnosis”) and hypothesised that the appellant was in a dissociative state at the time of the stabbing.
Dr Tan’s report, as reproduced in the judgment extract, suggested that the appellant was “blank” in her mind, did not realise she had stabbed the Deceased, and only realised what she had done after the stabbing. Dr Tan concluded that she qualified for diminished responsibility because she had an abnormality of mind induced by her mental disorder that substantially impaired her mental responsibility. This dissociative-state hypothesis was central: it was used to support the proposition that she was both unaware and incapable of controlling her actions at the relevant time.
However, the Court of Appeal’s ultimate decision on conviction did not rest on accepting diminished responsibility. Instead, the court found that the evidence was sufficient to avail the appellant of grave and sudden provocation. This approach reflects a common appellate concern in criminal appeals: where the evidence supports a partial defence on the record, the appellate court may apply the correct legal characterisation even if the defence was not fully articulated at trial, provided the evidential basis is present and the accused’s fair trial rights are not compromised.
On grave and sudden provocation under Exception 1, the Court of Appeal applied the two-part structure: a subjective test and an objective test. The subjective test focuses on whether the accused was deprived of self-control at the time of the act. The objective test focuses on whether the provocation was sufficiently grave to deprive a reasonable person of self-control. In this case, the subjective inquiry turned on the appellant’s contemporaneous accounts to the police. The extract indicates that the appellant’s police statements evolved: she initially denied involvement, then admitted stabbing for the first time in her third statement. Her core account was that the Deceased had physically and verbally abused her and, crucially, threatened her in the moments before the fatal attack by uttering: “Tomorrow. You. Go. Agent.” The appellant understood this to mean she would be sent back to her employment agency and repatriated to Myanmar in debt to her agents, given that Mr S was her third employer in about four months.
The Court of Appeal also considered the circumstances surrounding the offence. The evidence showed that the appellant stabbed the Deceased multiple times after the alleged threat. The court would have assessed whether the threat could reasonably be regarded as grave provocation in the context of the appellant’s circumstances, including her vulnerability as a foreign domestic worker and the immediate fear of being returned to her agency and repatriated in debt. The subjective element was supported by the appellant’s account that she became “very angry” and that the threat was the trigger for the stabbing. The objective element required the court to evaluate whether such a threat—under the particular factual matrix—was capable of provoking a sudden loss of self-control in a person of ordinary temperament.
Having concluded that the evidential requirements for Exception 1 were met, the Court of Appeal allowed the appeal against conviction. The court then convened a further hearing on 26 August 2025 to address the amended charge and sentencing. The appellant was convicted on an amended charge of culpable homicide not amounting to murder punishable under s 304(a) of the Penal Code. This reflects the doctrinal consequence of a successful partial defence: the law reduces murder to culpable homicide not amounting to murder, recognising that the accused’s culpability is lessened by the provocation.
On sentencing, the Court of Appeal reduced the term of imprisonment from life to 17 years. The extract indicates that the trial judge had imposed life imprisonment because there was reason to believe the appellant was only 17 at the time of the offence. The appellate court’s reduction to 17 years suggests that, while the appellant’s youth remained a relevant mitigating factor, the principal change was the alteration of the conviction from murder to culpable homicide not amounting to murder. The court’s sentencing analysis would have applied established principles: proportionality to the reduced offence, the gravity of the conduct (including the multiple stab wounds), and the mitigating circumstances arising from the partial defence and the appellant’s age.
What Was the Outcome?
The Court of Appeal allowed the appeal against conviction. Although the appellant had relied solely on diminished responsibility at trial, the court held that the evidence was sufficient to establish grave and sudden provocation under Exception 1 to s 300 of the Penal Code. Accordingly, the court convicted her on an amended charge of culpable homicide not amounting to murder under s 304(a) of the Penal Code.
On sentencing after a further hearing, the Court of Appeal set aside the life imprisonment sentence and imposed a reduced imprisonment term of 17 years. The practical effect is that the appellant’s criminal liability was reclassified from murder to culpable homicide not amounting to murder, with a correspondingly lower custodial sentence.
Why Does This Case Matter?
Zin Mar New v Public Prosecutor is significant for practitioners because it illustrates how appellate courts may apply the correct partial defence based on the evidential record, even where the defence was not expressly advanced at trial. The case underscores that the legal characterisation of an offence can turn on how the evidence satisfies the statutory elements of partial defences, and that courts will scrutinise both the accused’s account and the surrounding circumstances to determine whether the statutory thresholds are met.
For criminal defence counsel, the decision also highlights the importance of aligning psychiatric and factual narratives. The appellant’s trial strategy focused on diminished responsibility, supported by expert evidence of dissociation. Yet the appellate outcome turned on grave and sudden provocation, grounded in the appellant’s contemporaneous police statements and the immediate threat she perceived. This demonstrates that, in appropriate cases, factual provocation may provide a more direct route to partial liability reduction than psychiatric impairment—depending on what the evidence actually establishes.
For prosecutors and trial judges, the case serves as a reminder that the evidential basis for partial defences may be present even if the defence is not pursued in submissions. It also reinforces the structured approach to Exception 1: the subjective test (deprivation of self-control) and the objective test (gravity of provocation) must both be satisfied. The decision further shows that sentencing outcomes can change materially once the conviction is altered, particularly where the accused is likely a minor and where the partial defence reduces the offence from murder to culpable homicide not amounting to murder.
Legislation Referenced
- Penal Code (Cap 224, 2008 Rev Ed) — s 300 (including Exception 1 and Exception 7)
- Penal Code (Cap 224, 2008 Rev Ed) — s 302(2)
- Penal Code (Cap 224, 2008 Rev Ed) — s 304(a)
Cases Cited
- [2004] SGHC 244
- [2023] SGHC 146
- [2025] SGCA 44
Source Documents
This article analyses [2025] SGCA 44 for legal research and educational purposes. It does not constitute legal advice. Readers should consult the full judgment for the Court's complete reasoning.