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
- Judges: Andrew Phang Boon Leong JCA, Steven Chong JCA and Chao Hick Tin SJ
- Appellant: Daryati
- Respondent: Public Prosecutor
- Procedural Form: Ex tempore judgment
- Legal Area(s): Criminal Law — Offences; Criminal Law — Special exceptions
- Offence Convicted: Murder under s 300(c) of the Penal Code (Cap 224, 2008 Rev Ed)
- Defence in Issue: Diminished responsibility (Exception 7 to s 300 of the Penal Code)
- Key Substantive Issue: 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
- Trial Court Reference: Public Prosecutor v Daryati [2021] SGHC 135
- Judgment Length: 14 pages, 4,109 words
- 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 national who worked as a domestic helper for the deceased and her family, sought to rely on the defence of diminished responsibility under Exception 7 to s 300. The defence turned on whether, at the time of the killing, the appellant was suffering from an abnormality of mind arising from a recognised mental condition, and whether that abnormality substantially impaired her mental responsibility for her acts and omissions.
The Court of Appeal (in an ex tempore judgment) reaffirmed the structured, three-limb test for diminished responsibility. Applying that framework, the court rejected the appellant’s expert evidence and found that the second limb—namely, proof that the abnormality of mind arose from a condition of arrested or retarded development, inherent causes, or disease or injury—was not established on the evidence. The court also agreed with the trial judge that the first and third limbs were not satisfied.
Practically, the decision highlights the evidential burden on an accused person who seeks to raise diminished responsibility: expert diagnoses must rest on an adequate factual substratum, and courts will scrutinise whether the diagnosis is consistent with objective evidence and the accused’s own contemporaneous accounts, including functional impairment. The case is therefore significant for both the prosecution and the defence in Singapore’s murder jurisprudence.
What Were the Facts of This Case?
The appellant, Daryati, was convicted of murder for killing Mdm Seow Kim Choo (“the deceased”). She was employed as a domestic helper for the deceased and her family at the material time. The appeal did not dispute the broad background facts or the trial judge’s findings on the circumstances of the killing; instead, the appeal focused narrowly on whether the appellant could avail herself of the special exception of diminished responsibility under Exception 7 to s 300 of the Penal Code.
At trial, the appellant’s case was that she suffered from a mental condition that impaired her mental responsibility when she committed the offence. In particular, she relied on expert psychiatric evidence that she was suffering from persistent depressive disorder with intermittent depressive disorder. The defence’s narrative was that the appellant’s mental state had deteriorated over time and that, at the time of the murder, she was in a heightened state of arousal that increased her propensity to violence.
The prosecution’s position, accepted by the trial judge and upheld by the Court of Appeal, was that the evidential foundation for diminished responsibility was not made out. The court’s reasoning focused heavily on whether the appellant’s alleged depressive disorder was supported by reliable evidence, including whether she experienced functional impairment consistent with such a diagnosis. The court also examined whether the symptoms relied upon by the defence expert were consistent with objective evidence and with the appellant’s own testimony and contemporaneous diary entries.
In evaluating the mental condition claim, the Court of Appeal compared two expert perspectives: Dr Tommy Tan (for the defence) and Dr Jaydip Sarkar (for the prosecution). The court ultimately found that Dr Tan’s diagnosis was not supported by the requisite factual basis. The court noted that Dr Tan’s report omitted to account for functional impairment, which is a key element for diagnosing persistent depressive disorder or major depressive disorder. The court further found discrepancies between Dr Tan’s reliance on certain symptoms and the appellant’s own evidence at trial, as well as objective evidence from those who observed her during her employment.
What Were the Key Legal Issues?
The central legal issue was whether the appellant satisfied the defence of diminished responsibility under Exception 7 to s 300 of the Penal Code. Exception 7 provides a partial defence to murder where the accused, at the time of the act, was suffering from an abnormality of mind that substantially impaired her mental responsibility. The Court of Appeal emphasised that the defence is not established by diagnosis alone; it must satisfy a structured test.
In particular, the court had to determine whether the appellant met the three elements of diminished responsibility. First, whether she was suffering from an abnormality of mind (the first limb). Second, whether that abnormality arose from a recognised source—arrested or retarded development, inherent causes, or disease or injury (the second limb). Third, whether the abnormality substantially impaired her mental responsibility for her acts and omissions in relation to the offence (the third limb).
Within the second limb, the case turned on whether the appellant’s depressive disorder was properly established as a mental condition arising from disease or injury, and whether the evidence supported that she was actually suffering from persistent depressive disorder with intermittent depressive disorder at the relevant time. The court also had to consider whether the defence expert’s diagnosis was reliable given the lack of functional impairment evidence and the inconsistencies identified between the expert’s symptom list and the appellant’s own accounts.
How Did the Court Analyse the Issues?
The Court of Appeal began by restating the three-limb test for diminished responsibility, citing its earlier decision in Nagaenthran a/l K Dharmalingam v Public Prosecutor and another appeal [2019] 2 SLR 216 at [21]. The court then applied the test to the appellant’s submissions. While the appellant advanced arguments on all three limbs, the court’s analysis focused on why the defence failed at the second limb, and why the first and third limbs were also not satisfied.
On the first limb, the appellant argued that she had 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 a loss of self-control. She also argued that even if there was premeditation, her actions flowed from a disordered mind, emphasising that her behaviour was irrational in the circumstances. Finally, she urged the court to consider the common circumstances faced by migrant domestic workers when assessing whether she was labouring under an abnormality of mind.
The Court of Appeal rejected these submissions. Although the court accepted that the appellant might be a “closed-off” person whose mood changes were not readily observable to others, it found that the evidence did not support the existence of an abnormality of mind of the required kind. The court’s approach was evidentially anchored: it assessed whether the claimed mental state was consistent with objective evidence, the appellant’s own testimony, and contemporaneous records such as diary entries. The court did not treat the appellant’s subjective narrative as sufficient where it conflicted with other evidence.
On the second limb, the appellant’s case depended largely on Dr Tan’s expert opinion diagnosing persistent depressive disorder with intermittent depressive disorder. The Court of Appeal, however, found that Dr Tan’s evidence should not be accepted. The court’s critique was twofold: (1) Dr Tan’s report omitted to address functional impairment, and (2) the symptoms relied upon were largely derived from the appellant’s self-reported account, which was not verified against objective evidence that would have been available.
The court highlighted that functional impairment is an important criterion for diagnosing persistent depressive disorder or major depressive disorder. Dr Tan’s report “conveniently omits” to account for functional impairment, despite acknowledging its importance. The Court of Appeal then pointed to clear objective evidence and evidence from the appellant herself indicating that she did not experience functional impairment in either Indonesia or Singapore. This was not a minor omission; it went to the reliability of the diagnosis and therefore to whether the abnormality of mind could be said to have arisen from disease or injury.
In addition, the court found that several symptoms relied upon by Dr Tan were inconsistent with objective evidence and the appellant’s own testimony. Dr Tan relied on symptoms such as depressed mood, eating less, loss of weight, and suicidal thoughts. The Court of Appeal noted that these were “at odds” with the appellant’s own evidence at trial and with objective evidence. When Dr Tan was confronted with evidence negating these symptoms, he maintained the diagnosis without adequate justification. The Court of Appeal concluded that there was “no hesitation” in rejecting Dr Tan’s evidence because of the lack of requisite factual substratum and the want of sound reasons.
The court then elaborated on the objective evidence. It referred to testimony from the appellant’s co-worker (Don Hayati), as well as from the deceased’s husband (Mr Ong) and the appellant’s eldest son (Wei Yang), who did not report changes in the appellant’s work performance. The appellant herself testified that she could handle her job scope and complete her assigned chores daily, notwithstanding difficulty focusing. The court also relied on the appellant’s ability to plan ahead and reason clearly, including the plotting involved in stealing money, retrieving her passport, and escaping. The court further noted that the appellant formed relationships socially, befriending other migrant workers and receiving assistance such as spare handphones.
Crucially, the Court of Appeal found similar absence of functional impairment in Indonesia. The appellant had completed high school, worked at a prawn factory for about two years without work problems, and formed friendships and a romantic relationship. After leaving the factory for training, she met training requirements. 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. These admissions undermined the defence diagnosis and supported the court’s conclusion that the second limb was unproven.
The Court of Appeal also addressed discrepancies in the appellant’s symptom reporting. It examined the appellant’s diary entries and her account to Dr Tan. The court observed that while the appellant argued she was closed-off and thus her mood changes were not observed by others, there remained a “large discrepancy” between her testimony in court and the account she gave Dr Tan. The court further found that Dr Tan’s summary of the appellant’s reported symptoms did not provide a full picture of her mental state after moving to Singapore, as contemporaneously documented in the diary entries. This reinforced the court’s view that Dr Tan’s opinion lacked a reliable factual foundation.
Given these findings, the Court of Appeal held that the trial judge was correct to reject Dr Tan’s evidence, leaving the second limb unproven. The court further agreed that the first and third limbs were not satisfied. While the excerpt provided does not set out the full analysis of the third limb, the court’s approach indicates that without establishing a credible abnormality of mind arising from disease or injury, it is difficult to show that mental responsibility was substantially impaired. The court also treated the appellant’s planning, social functioning, and occupational capability as inconsistent with the degree of impairment required for diminished responsibility.
What Was the Outcome?
The Court of Appeal dismissed the appellant’s appeal and upheld her conviction for murder under s 300(c) of the Penal Code. The court found no merit in the defence of diminished responsibility and agreed with the trial judge that the defence was not established on the evidence.
As a result, the appellant remained convicted of murder, and the special exception of diminished responsibility did not apply. The practical effect is that the conviction stands without reduction to a lesser offence that diminished responsibility might have permitted.
Why Does This Case Matter?
Daryati v Public Prosecutor is important because it demonstrates how Singapore courts evaluate diminished responsibility claims in murder cases. The decision underscores that the defence is not satisfied by a psychiatric label or expert diagnosis alone. Courts require an evidentially sound diagnosis grounded in reliable facts, including whether the accused experienced functional impairment consistent with the claimed disorder.
For practitioners, the case provides a clear warning about the evidential weaknesses that can defeat diminished responsibility. Expert reports that rely heavily on self-reported symptoms without adequate verification, or that omit key diagnostic features such as functional impairment, may be rejected. The Court of Appeal’s reasoning also shows that courts will scrutinise inconsistencies between expert accounts, trial testimony, and contemporaneous documents like diary entries.
From a broader doctrinal perspective, the case reaffirms the structured three-limb framework and the need to prove each limb. Even where an accused argues irrationality or loss of self-control, the defence still requires proof of an abnormality of mind arising from a recognised source and substantial impairment of mental responsibility. The decision therefore has value as a practical guide for both defence counsel preparing psychiatric evidence and prosecutors challenging its reliability.
Legislation Referenced
- Penal Code (Cap 224, 2008 Rev Ed), s 300(c)
- Penal Code (Cap 224, 2008 Rev Ed), Exception 7 to s 300 (diminished responsibility)
Cases Cited
- Nagaenthran a/l K Dharmalingam v Public Prosecutor and another appeal [2019] 2 SLR 216
- Public Prosecutor v Daryati [2021] SGHC 135
- 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.