Facing Charges? Learn About The Defence Of Unsound Mind In Singapore

by 21 February 2025Knowledge & Insights

Imagine being accused of a crime you couldn’t fully comprehend due to a severe mental condition. The law recognises that individuals suffering from certain mental disorders may not be entirely responsible for their actions. This is where the Defence of Unsound Mind becomes relevant.

In Singapore, this legal defence offers the accused an opportunity to prove that they could not understand the nature or wrongfulness of their actions at the time of the offence.

This blog will discuss the process, key requirements, and common misconceptions about the Defence of Unsound Mind in Singapore. Whether seeking clarity for yourself or a loved one, this guide will help you navigate the essential steps.

Understanding The Defence Of Unsound Mind

The Defence of Unsound Mind is codified under Section 84 of the Penal Code in Singapore. It states that a person is not criminally responsible for an act if, due to a mental disorder, they could not understand the nature or wrongfulness of their actions at the time of committing the offence.

For this defence to succeed, the Court requires clear proof that the accused was suffering from a mental illness that impaired their judgment during the incident.

 

Key Requirements For The Defence

Raising Defence of Unsound Mind in Singapore requires meeting specific legal criteria. The Court evaluates not only the existence of a mental disorder but also its impact on the accused’s cognitive abilities and the timing of the condition. Below is a detailed explanation of the key requirements:

1. Existence Of A Mental Disorder

To invoke this defence, the accused must have been diagnosed with a recognised mental disorder. The medical community must acknowledge the disorder and be supported by expert evidence, such as psychiatric reports from qualified professionals.

Common conditions considered by the Court include schizophrenia, bipolar disorder, severe depression with psychotic features, and epilepsy (if it causes a temporary loss of awareness). Other disorders, such as dementia, may also be accepted if they significantly impair cognitive functions.

The Court relies heavily on the testimony and reports of psychiatrists to establish the legitimacy of the diagnosis. Without credible medical evidence, the defence is unlikely to succeed.

Note: Simply having a diagnosis is not enough; it must be proven that the disorder directly influenced the accused’s actions at the time of the offence.

2. Impact On Understanding

Even if a mental disorder exists, it must be shown that it severely impaired the accused’s capacity to understand the nature or consequences of their actions or their capacity to distinguish right from wrong.

The defence requires proving that the accused could not comprehend what they were doing or that what they were doing was legally or morally wrong. For instance, if an individual with severe schizophrenia committed an act while experiencing a psychotic episode that distorted their perception of reality, they may qualify for this defence.

The accused must demonstrate that the mental disorder rendered them incapable of forming the necessary intent (or mens rea) to commit the crime. In other words, their mental condition prevented them from having the guilty mind required for criminal liability.

This can be proven through medical records, expert psychiatric testimony, and even witness statements from those who interacted with the accused before or after the incident, highlighting their impaired state of mind.

3. Timing Of The Condition

A crucial requirement for the defence is that the mental disorder must have been present and active at the exact time the offence was committed. The accused must prove that they were suffering from the disorder during the act, not before or after it.

Mental disorders can fluctuate in severity. For example, a person with bipolar disorder may experience periods of normalcy between manic or depressive episodes. If the accused were in a stable mental state when the offence occurred, the defence would not apply, even if they were diagnosed with a disorder before or after the incident.

The onus is on the defence to provide evidence that the accused was in an impaired mental state at the time of the crime. This is typically established through:

  • Psychiatric evaluations were conducted shortly after the offence.
  • Testimonies from individuals who witnessed the accused’s behaviour during the incident.
  • Medical history shows a pattern of episodes consistent with the offence’s timing.

 

Possible Outcomes When The Defence Succeeds

If the Defence of Unsound Mind succeeds, the accused is acquitted of criminal responsibility. However, this does not mean they are immediately released or free to go. Instead, the legal system takes measures to ensure both the safety of the accused and the public, given the potential risks posed by untreated or ongoing mental disorders.

Below are the possible outcomes when the defence is successfully raised:

Acquittal With Mandatory Institutionalisation

In many cases, if the Court finds that the accused committed the offence but was of unsound mind at the time, they may be acquitted of criminal charges according to Section 251 of the Criminal Procedure Code. However, the Court may also order that the accused be detained in a psychiatric institution for treatment and observation.

The goal is not to punish but to ensure that the accused receives proper psychiatric care and that they no longer pose a danger to themselves or others.

The length of stay in the psychiatric institution depends on the severity of the mental disorder and the accused’s progress in treatment. The institution will conduct regular reviews to assess whether continued detention is necessary.

Conditional Release After Treatment

The accused may sometimes be released after treatment, provided they meet certain conditions. These conditions may include:

  • Mandatory Follow-Up Treatment: The accused may be required to undergo ongoing psychiatric care, such as counselling or medication.
  • Regular Psychiatric Evaluations: The accused may need to attend regular check-ups with mental health professionals to monitor their condition.
  • Restrictions On Certain Activities: Depending on the nature of the offence, the Court may impose specific restrictions (e.g., prohibiting contact with certain individuals or barring access to certain locations).

If the accused fails to comply with these conditions, they may be returned to a psychiatric institution or subjected to other legal actions.

Continued Monitoring And Review

Even after release, the accused’s mental state may be subject to periodic review by psychiatric professionals and the Court.

Continued monitoring ensures that the accused remains mentally stable and is not at risk of reoffending due to a relapse or worsening of their condition.

This may involve regular reports from psychiatrists to the Court, check-ins with probation officers, or interviews with social workers.

Right To Appeal Detention

If the accused or their family believes that detention in a psychiatric institution is no longer necessary, they can apply for a review or appeal the detention order.

The application must be supported by psychiatric evaluations showing the accused no longer poses a risk. The Court will consider the application and decide whether to alter or lift the detention order.

 

Why Legal Representation Is Important

Successfully raising the Defence of Unsound Mind is complex and requires substantial legal and medical expertise. The best criminal lawyers in Singapore, like those at Tembusu Law, can:

  • Engage top psychiatrists for credible evaluations.
  • Gather strong evidence to support the defence.
  • Represent you effectively in Court, ensuring your rights are upheld.

With the right legal team, you can achieve a favourable outcome better.

 

Conclusion About The Defence Of Unsound Mind

The Defence of Unsound Mind can offer a lifeline to individuals suffering from severe mental disorders when facing criminal charges. However, proving it requires expert law knowledge and access to reliable medical professionals.

If you or your loved one is in such a situation, Tembusu Law has the best criminal lawyers in Singapore ready to provide the guidance you need.

Contact us today for a free consultation and take the first step towards securing the right defence.

 

Frequently Asked Questions About The Defence Of Unsound Mind

How Can I Prove An Unsound Mind In Court?

To successfully prove an unsound mind in Court, you must provide credible psychiatric evidence from a qualified mental health professional. Additionally, witness testimonies from those who observed your behaviour before and after the incident, as well as past medical records showing a history of mental illness, can strengthen your case.

What Happens If The Defence Succeeds?

If the Defence of Unsound Mind succeeds, the Court will acquit you of the charges. However, you may be detained in a psychiatric institution for treatment and observation. Detention aims to ensure that you receive appropriate care and do not pose a danger to yourself or others.

Can Any Mental Disorder Be Used For This Defence?

No, not every mental disorder qualifies for this defence. Only severe mental disorders that impair judgment and the ability to distinguish right from wrong—such as schizophrenia, bipolar disorder (during manic episodes), or severe depression with psychotic features—are typically considered by the Court.

How Long Will I Be Detained If Acquitted Due To Unsound Mind?

The duration of detention depends on the severity of your mental disorder and the level of risk you pose to society. Detention is reviewed periodically by medical professionals and the Court to assess whether continued institutionalisation is necessary or if you can be safely released under certain conditions.

About the author

About the author

Tembusu Law

Jonathan is the Founder and Managing Director of Tembusu Law. He is also the founder of LawGuide Singapore, a prominent legaltech startup which successfully created and launched Singapore’s first legal chatbot in 2017.

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