Case Details
- Citation: [2022] SGCA 30
- Title: Daryati v Public Prosecutor
- Court: Court of Appeal of the Republic of Singapore
- Case Number: Criminal Appeal No 14 of 2021
- Date of Decision: 31 March 2022
- Judgment Type: Ex tempore judgment
- Judges: Andrew Phang Boon Leong JCA, Steven Chong JCA and Chao Hick Tin SJ
- Appellant: Daryati (Indonesian national; domestic helper)
- Respondent: Public Prosecutor
- Offence: Murder
- Key Statutory Provision: s 300(c) of the Penal Code (Cap 224, 2008 Rev Ed)
- Defence in Issue: Exception 7 to s 300 (diminished responsibility)
- Core Legal Question: Whether the appellant was suffering from persistent depressive disorder with intermittent depressive disorder at the time of the murder, satisfying the three limbs of diminished responsibility
- Length of Judgment: 14 pages, 4,109 words
- Related High Court Decision: Public Prosecutor v Daryati [2021] SGHC 135
- Cases Cited (as provided): [2021] SGHC 135; [2022] SGCA 30
Summary
Daryati v Public Prosecutor concerned an appeal against a conviction for murder under s 300(c) of the Penal Code. The appellant, an Indonesian domestic helper, had killed her employer’s family member, Mdm Seow Kim Choo (“the deceased”). The appeal did not dispute the occurrence of the killing, but instead focused narrowly on whether the appellant could avail herself of the defence of diminished responsibility under Exception 7 to s 300 of the Penal Code.
The Court of Appeal reiterated the structured, three-limb test for diminished responsibility: (1) an abnormality of mind; (2) that abnormality arising from one of the statutorily recognised sources (including disease or injury); and (3) that abnormality substantially impairing the accused’s mental responsibility for the acts and omissions constituting the offence. Applying that framework, the Court held that the defence was not made out. In particular, the Court found that the second limb remained unproven because the trial judge was correct to reject the appellant’s expert psychiatric evidence.
Ultimately, the Court of Appeal agreed with the High Court that neither the first limb nor the third limb was satisfied on the evidence. The conviction for murder therefore stood.
What Were the Facts of This Case?
The appellant was employed as a domestic helper by the deceased and her family. The killing occurred in the course of that employment. While the Court of Appeal stated that it would not repeat the undisputed background facts and the trial judge’s decision (as these were fully set out in Public Prosecutor v Daryati [2021] SGHC 135), the appeal record made clear that the appellant’s mental state at the time of the killing was central to her defence strategy.
At trial, the appellant sought to rely on diminished responsibility. Her case was that she was suffering from a depressive disorder—specifically persistent depressive disorder with intermittent depressive disorder—at the time of the murder. She argued that this mental condition amounted to an “abnormality of mind” and that it substantially impaired her mental responsibility for her conduct. The defence thus required the court to assess not only whether the appellant had a diagnosed psychiatric condition, but also whether the statutory requirements were satisfied on the evidence.
Two competing expert perspectives emerged. The appellant’s expert, Dr Tommy Tan (“Dr Tan”), diagnosed persistent depressive disorder (and a relapse of major depressive disorder episode) using DSM-5 criteria. The prosecution’s case, and the trial judge’s findings, rejected Dr Tan’s diagnosis. The Court of Appeal’s ex tempore reasons focused heavily on why Dr Tan’s evidence lacked an adequate factual foundation and why the objective and testimonial evidence did not support the claimed functional impairment and symptom profile.
In assessing the appellant’s mental condition, the Court of Appeal placed significant weight on functional impairment—an element Dr Tan acknowledged as important for diagnosing persistent depressive disorder or major depressive disorder. The Court found that the appellant did not experience functional impairment either in Indonesia or in Singapore. Evidence from the appellant’s co-worker, employer family members, and her own testimony indicated that she could perform her job scope, complete daily chores, and did not make errors at work. The Court also considered the appellant’s behaviour after the killing, including planning and reasoning, as indicative of cognitive functioning inconsistent with the claimed level of mental impairment.
What Were the Key Legal Issues?
The principal legal issue was whether the appellant was entitled to the defence of diminished responsibility under Exception 7 to s 300 of the Penal Code. This required the Court to determine whether the appellant satisfied all three limbs of the test: first, whether she was suffering from an abnormality of mind; second, whether that abnormality arose from an accepted source such as disease or injury; and third, whether the abnormality substantially impaired her mental responsibility for the offence.
A subsidiary but crucial issue was evidential: whether the appellant’s psychiatric evidence, particularly Dr Tan’s diagnosis, should be accepted. The Court of Appeal had to decide whether Dr Tan’s opinion was supported by a sufficient factual substratum and sound reasoning, especially in light of evidence that contradicted key symptoms and the absence of functional impairment.
Finally, the Court had to assess whether, even if a psychiatric condition existed, the evidence supported the conclusion that the appellant’s mental responsibility was substantially impaired at the time of the murder. This required the court to evaluate the relationship between the alleged disorder and the appellant’s conduct, including whether her behaviour reflected impaired mental responsibility or instead reflected planning and rationality.
How Did the Court Analyse the Issues?
The Court of Appeal began by restating the governing legal test for diminished responsibility. It referred to its earlier decision in Nagaenthran a/l K Dharmalingam v Public Prosecutor and another appeal [2019] 2 SLR 216 at [21], setting out the three elements. The Court then applied the test to the appellant’s submissions, which were organised around the first limb (abnormality of mind), the second limb (source of abnormality), and the third limb (substantial impairment).
On the first limb, the appellant argued that she experienced an abnormally reduced mental capacity to exercise self-control after the deceased screamed and she realised her plan had gone wrong. She pointed to the number of wounds and the amount of force used as evidence of loss of self-control. She also contended that even if there was premeditation, her actions flowed from a disordered mind, emphasising purported irrationality in the circumstances. In addition, she urged the court to consider common circumstances faced by migrant domestic workers when assessing whether she was labouring under an abnormality of mind.
The Court of Appeal rejected these arguments. It agreed with the trial judge that the first limb was not satisfied. While the Court did not accept the appellant’s framing of her conduct as evidence of an abnormality of mind, it also treated the overall evidential picture—especially planning behaviour and the lack of corroborated psychiatric impairment—as inconsistent with the claimed abnormality. The Court’s reasoning indicates that “abnormality of mind” is not established merely by showing that the accused acted violently or that the violence was extensive; it must be supported by psychiatric evidence and by a coherent factual basis demonstrating a relevant mental abnormality at the time of the offence.
On the second limb, the appellant’s submissions centred on whether Dr Tan’s diagnosis should have been preferred. She argued that other people did not objectively observe her emotions, which she said was consistent with her being closed-off and needing time to seek help. She further argued that subjective reporting could be sufficient for diagnosing persistent depressive disorder under DSM-5. She also challenged Dr Sarkar’s approach, contending that Dr Sarkar’s inference from a diary entry was wrong and that DSM-5 and ICD-10 criteria were effectively similar. The appellant maintained that, in any event, both criteria were fulfilled.
The Court of Appeal’s analysis of the second limb was decisive. It held that there was “no merit” in the defence because the trial judge was correct to reject Dr Tan’s evidence. The Court explained that Dr Tan’s report omitted to account for functional impairment, which Dr Tan himself acknowledged as important for diagnosing persistent depressive disorder or major depressive disorder. The Court found clear objective evidence and evidence from the appellant herself showing that she did not experience functional impairment in either Indonesia or Singapore.
In addition, the Court found that many of the symptoms relied on by Dr Tan were largely derived from the appellant’s self-reported account and were not verified against objective evidence that would have been available. The Court highlighted that four symptoms—depressed mood, eating less, loss of weight and suicidal thoughts—were at odds with objective evidence and the appellant’s own testimony at trial. When Dr Tan was confronted with evidence negating these symptoms and the lack of functional impairment, he maintained his diagnosis without adequate justification. The Court therefore rejected Dr Tan’s evidence for lack of factual substratum and insufficient sound reasons.
The Court elaborated by examining functional impairment and symptom consistency. It noted that the appellant’s co-worker, Don Hayati, and the deceased’s husband (Mr Ong) and eldest son (Wei Yang) did not report changes in her work performance. This was corroborated by the appellant’s own testimony that she could handle her job scope and complete assigned chores daily, notwithstanding difficulty focusing. The Court also considered that the appellant displayed planning and reasoning: she plotted to steal money, retrieve her passport and escape, including drawing a map of the house layout, enlisting help, and selecting an opportune moment to strike. Socially, she formed relationships and friendships, including befriending another Indonesian maid and a Bangladeshi national who gave her a spare handphone. These behaviours were treated as inconsistent with the claimed level of functional impairment.
Turning to the period in Indonesia, the Court similarly found no functional impairment. The appellant testified that she completed high school, passed her subjects, worked at a prawn factory for about two years, and attended a training centre before coming to Singapore. At the factory and training centre, she had no problems with work, made friends, and formed a romantic relationship. Dr Tan, in cross-examination, accepted that the appellant did not show functional impairment in Indonesia and did not show signs of functional impairment in Singapore based on what she said in court. This concession further undermined the diagnostic narrative that she suffered from persistent depressive disorder with intermittent depressive disorder accompanied by functional impairment.
Finally, the Court addressed the third limb—substantial impairment of mental responsibility. It agreed with the trial judge that the third limb was not satisfied. The reasoning flowed from the Court’s rejection of the second limb: if the diagnosis and its factual basis were not accepted, it was difficult to conclude that the appellant’s mental responsibility was substantially impaired. Moreover, the Court’s emphasis on planning and rational behaviour suggested that the appellant’s mental responsibility was not substantially impaired in the manner required by Exception 7.
Although the excerpt provided truncates the later parts of the judgment, the Court’s approach is clear from the sections reproduced: it scrutinised the internal coherence of the psychiatric evidence against objective facts, and it treated functional impairment and symptom credibility as central to whether the statutory defence was made out.
What Was the Outcome?
The Court of Appeal dismissed the appeal. It affirmed the trial judge’s rejection of Dr Tan’s evidence and held that the defence of diminished responsibility was not proven. As a result, the appellant’s conviction for murder under s 300(c) of the Penal Code remained.
Practically, the decision confirms that diminished responsibility in Singapore is not a “diagnosis-only” defence. Even where an accused presents expert evidence of a depressive disorder, the court will examine whether the diagnosis is supported by a reliable factual substratum and whether the statutory limbs—especially functional impairment and substantial impairment of mental responsibility—are satisfied on the totality of evidence.
Why Does This Case Matter?
Daryati v Public Prosecutor is significant for practitioners because it illustrates the Court of Appeal’s rigorous evidential scrutiny in diminished responsibility cases. The decision reinforces that the second limb is not satisfied merely by the existence of a psychiatric label; the court must be satisfied that the abnormality of mind arose from a disease or injury and that the diagnosis is grounded in credible facts, including objective evidence where available.
The case also highlights the importance of functional impairment in diagnosing persistent depressive disorder or major depressive disorder. Where expert evidence omits or inadequately addresses functional impairment, and where objective evidence contradicts key symptoms, courts may reject the diagnosis. This is particularly relevant for defence counsel who rely on DSM-5 or ICD-10 criteria: the criteria must be applied to a factual record that supports the diagnosis, not to selective or unverified symptom reporting.
For prosecutors, the decision provides a roadmap for challenging diminished responsibility: focus on contradictions between expert reports and objective evidence (such as work performance, social functioning, and behavioural planning), and press for justification when an expert maintains a diagnosis despite confrontation with contrary evidence. For law students, the case is a useful illustration of how the three-limb test operates in practice and how courts evaluate psychiatric testimony within the legal framework of Exception 7 to s 300.
Legislation Referenced
- Penal Code (Cap 224, 2008 Rev Ed), s 300(c) [CDN] [SSO]
- Penal Code (Cap 224, 2008 Rev Ed), Exception 7 to s 300 (diminished responsibility)
Cases Cited
- Public Prosecutor v Daryati [2021] SGHC 135
- Nagaenthran a/l K Dharmalingam v Public Prosecutor and another appeal [2019] 2 SLR 216
- Daryati v Public Prosecutor [2022] SGCA 30
Source Documents
This article analyses [2022] SGCA 30 for legal research and educational purposes. It does not constitute legal advice. Readers should consult the full judgment for the Court's complete reasoning.