1. Meaning of Unsoundness of Mind
Unsoundness of mind means a mental condition in which a person lacks the necessary mental capacity to properly understand or appreciate the nature and consequences of their conduct.
In the context of criminal law, it becomes relevant when a person’s mental condition is so severe that, at the time of committing the act, the person is unable to understand what they are doing or is unable to realise that the act is wrong or against the law.
In simple words, unsoundness of mind means a state of mental incapacity that prevents a person from having the understanding necessary to be held criminally responsible for the act.
2. Section 22 BNS — Act of a Person of Unsound Mind
Bare Act Language
“Nothing is an offence which is done by a person who, at the time of doing it, by reason of unsoundness of mind, is incapable of knowing the nature of the act, or that he is doing what is either wrong or contrary to law.”
Meaning of Section 22
Section 22 provides a General Exception to a person who, because of unsoundness of mind, was incapable of understanding the nature of the act or of knowing that the act was wrong or contrary to law at the time it was committed.
In simple words, if a person’s mental condition is such that, when committing the act, he or she cannot understand what the act actually is or cannot understand that the act is wrong or against the law, the person may receive protection under Section 22.
“At the Time of Doing It”
The Bare Act specifically says:
“at the time of doing it”
This is very important. The person’s mental condition must be considered at the exact time when the act was committed.
It is not enough to show that the person had suffered from unsoundness of mind at some earlier or later time. The relevant question is whether the unsoundness of mind affected the person’s ability to understand the act when the act was actually done.
“By Reason of Unsoundness of Mind”
The Bare Act uses the words:
“by reason of unsoundness of mind”
This means there must be a connection between the person’s unsoundness of mind and the inability to understand the act.
The mere existence of a mental disorder or abnormality does not automatically provide protection. The person’s unsoundness of mind must have resulted in the incapacity described in Section 22.
“Incapable of Knowing the Nature of the Act”
The first form of incapacity mentioned in Section 22 is:
“incapable of knowing the nature of the act”
This means the person was unable to understand what he or she was actually doing because of unsoundness of mind.
For example, if a person’s mental condition prevents him from understanding the character or nature of his physical act, this part of Section 22 may become relevant.
“Or That He Is Doing What Is Either Wrong or Contrary to Law”
The second part deals with the person’s inability to understand that the act is:
“wrong or contrary to law.”
Thus, even if a person is physically aware of what he is doing, Section 22 may apply if, because of unsoundness of mind, he is incapable of understanding that the conduct is wrong or prohibited by law.
The provision therefore recognises two forms of relevant incapacity:
Unable to understand the nature of the act
OR
Unable to understand that the act is wrong or contrary to law
Core Principle of Section 22
The central idea is that criminal responsibility requires a certain level of mental understanding. Where, because of unsoundness of mind, a person lacks the capacity specified in Section 22 at the time of the act, the law provides a General Exception.
3. Essential Elements of Section 22 BNS — Act of a Person of Unsound Mind
The Act Must Be Committed by the Accused
The first requirement is that the person seeking the benefit of Section 22 must have done the act in question.
Section 22 does not create a general exemption from all criminal responsibility merely because a person suffers from unsoundness of mind. It operates in relation to a particular act alleged to constitute an offence.
Therefore, the court first considers the conduct attributed to the accused and then examines whether the accused’s mental condition brings that conduct within the General Exception.
Presence of Unsoundness of Mind
The next essential requirement is the existence of unsoundness of mind.
The Bare Act specifically uses the expression:
“by reason of unsoundness of mind”
This means that the person’s mental condition must be relevant to the inability described in Section 22.
The provision is therefore not concerned merely with whether the accused had unusual behaviour, emotional problems, a personality disorder, or some form of mental difficulty. The important issue is whether the person’s unsoundness of mind produced the legally relevant incapacity mentioned in the provision.
Unsoundness of Mind Must Exist at the Time of the Act
One of the most important requirements is found in the words:
“at the time of doing it”
The court must primarily examine the accused’s mental condition when the act was committed.
A person might have experienced mental illness before the incident and later recovered. Similarly, a person might develop a serious mental condition after the incident. These circumstances may be relevant evidence, but they do not by themselves establish the defence.
The decisive question is whether the required incapacity existed at the time of the particular act.
Simple Example
Suppose A suffers from a mental disorder for several years but commits an offence during a period in which he is fully capable of understanding what he is doing and that it is wrong.
The mere history of mental illness would not automatically entitle A to the protection of Section 22.
The Incapacity Must Be Because of Unsoundness of Mind
Section 22 does not merely require incapacity. It requires the incapacity to exist:
“by reason of unsoundness of mind”
There must therefore be a connection between the person’s mental condition and the inability to understand contemplated by the provision.
In simple language, the person must be unable to understand the relevant matter because of the unsoundness of mind.
This prevents a person from relying upon Section 22 merely because they were confused, intoxicated, careless, impulsive, or otherwise unable to understand something for reasons unrelated to unsoundness of mind.
Incapacity to Know the Nature of the Act
The first form of incapacity specifically recognised by Section 22 is:
“incapable of knowing the nature of the act”
This concerns the person’s ability to understand what they are actually doing.
A person may physically perform an act but, because of unsoundness of mind, may lack the mental ability to understand the character or nature of that conduct.
Simple Illustration
Suppose a person, because of a severe mental disturbance, performs an act while believing that he is performing something entirely different. If the evidence establishes that his mental condition made him incapable of understanding the nature of his conduct, this part of Section 22 may become relevant.
The focus is therefore on understanding the character of the act, not merely on whether the physical act occurred.
Incapacity to Know That the Act Is Wrong
Section 22 provides an alternative form of incapacity:
“that he is doing what is either wrong”
This covers a situation where the person may have some understanding of the physical nature of the act but, because of unsoundness of mind, is incapable of appreciating that the conduct is wrong.
Thus, the law does not require that the person be completely unaware of everything surrounding the act. What matters is whether the mental condition deprived the person of the relevant understanding recognised by the provision.
Incapacity to Know That the Act Is Contrary to Law
The provision further refers to:
“contrary to law”
This concerns the person’s inability to understand that the conduct is legally prohibited.
Therefore, Section 22 recognises two related forms of understanding concerning wrongfulness:
Knowing that the act is wrong
or
Knowing that the act is contrary to law
The precise application depends upon the facts and evidence of the particular case.
“Nature of the Act” and “Wrong or Contrary to Law” Are Distinct Concepts
These expressions should not be treated as completely identical.
Knowing the nature of the act concerns understanding what the person is doing.
Knowing that the act is wrong or contrary to law concerns understanding the wrongful or unlawful character of that conduct.
Therefore, Section 22 provides protection where the person’s unsoundness of mind produces the relevant incapacity in either of these areas.
Criminal Intention Is Not the Sole Test
Section 22 is not simply a question of whether the accused had a criminal intention.
The central concern is the person’s mental capacity to understand the nature and wrongfulness of the conduct.
A person may physically perform an act that would ordinarily constitute an offence, yet the General Exception may apply if the statutory requirements concerning unsoundness of mind and incapacity are established.
Thus, the focus is on legal mental capacity, rather than merely asking whether the person deliberately performed the physical act.
Medical Insanity Alone Is Not Sufficient
The existence of a medically diagnosed mental illness does not automatically satisfy Section 22.
A person may suffer from a psychiatric condition and still be capable of understanding:
what they are doing, and
that the act is wrong or contrary to law.
In such circumstances, the medical condition alone does not necessarily establish the legal defence.
This is why criminal law distinguishes between medical insanity and legal insanity.
Legal Insanity Is the Relevant Standard
Section 22 is concerned with legal insanity, meaning the specific mental incapacity recognised by the provision.
The court ultimately has to determine whether the evidence establishes that, because of unsoundness of mind, the accused was incapable of the understanding specified in Section 22 at the relevant time.
Medical evidence can assist the court in making this determination, but a medical diagnosis does not by itself decide the legal question.
The Mental Condition Must Be Connected With the Particular Act
Section 22 is concerned with the accused’s mental capacity in relation to the specific conduct under consideration.
Therefore, the court may examine the circumstances surrounding the incident to understand the accused’s mental condition at that particular time.
Evidence concerning the person’s behaviour before, during, and after the incident may be relevant, but the ultimate question remains whether the statutory incapacity existed when the act was committed.
The Question Is About the Relevant Time, Not Merely the General Condition
A person may have periods in which their mental condition changes.
Consequently, the fact that someone was mentally ill generally does not necessarily establish that they lacked the required understanding during the particular incident.
The court therefore focuses on the mental state at the relevant time.
This is one of the most important features distinguishing the Section 22 defence from a general claim that the accused has a mental disorder.
Burden of Establishing the Exception
Section 22 is a General Exception. When an accused relies upon such an exception, the issue of whether its requirements are satisfied becomes a matter for determination on the evidence.
The accused does not necessarily have to prove the defence in the same manner as the prosecution proves the ingredients of the offence. The law governing the burden of proving General Exceptions is therefore important while studying Section 22.
For exam purposes, remember that the prosecution must still establish the offence, while the accused who relies on Section 22 has the statutory burden associated with establishing the General Exception.
Evidence Relevant to Section 22
The court may consider different forms of evidence while determining whether the accused was legally insane at the relevant time.
Medical records, psychiatric history, expert opinions, previous treatment, behaviour surrounding the incident, statements or conduct of the accused, and other surrounding circumstances may become relevant.
However, no single piece of evidence automatically decides the issue.
The ultimate question remains whether the evidence establishes the specific incapacity required by Section 22.
The Defence Is Based on Incapacity, Not Merely Abnormal Behaviour
Unusual, irrational, aggressive, strange, or abnormal behaviour does not automatically establish the Section 22 defence.
The conduct must be examined in connection with the statutory requirement of incapacity to know the nature of the act or its wrongfulness/illegality because of unsoundness of mind.
Therefore:
Abnormal behaviour ≠ automatically legal insanity.
Section 22 Requires a Link Between Three Things
The provision can be understood through a simple legal chain:
Unsoundness of mind → causes relevant mental incapacity → incapacity exists at the time of the act
If this connection is not established, merely proving the existence of a mental disorder will not automatically result in the protection of Section 22.
4.Legal Insanity vs Medical Insanity Under Section 22 BNS
The distinction between legal insanity and medical insanity is extremely important while understanding Section 22 of the Bharatiya Nyaya Sanhita, 2023. A person may suffer from a medically recognised mental illness, but that does not automatically mean that the person gets the benefit of Section 22.
The law is concerned with the person’s mental capacity at the time of the act, rather than merely the existence of a medical condition.
| Basis | Legal Insanity | Medical Insanity |
|---|---|---|
| Meaning | Legal insanity refers to the specific mental incapacity recognised by Section 22 BNS for the purpose of criminal liability. | Medical insanity refers to a mental illness, disorder, or condition identified from a medical or psychiatric perspective. |
| Purpose | It is considered for determining whether a person should be held criminally responsible for an act. | It is primarily concerned with diagnosis, treatment, management, and medical assessment of a person’s mental condition. |
| Relevant Law | Governed by the requirements of Section 22 BNS. | Determined according to medical and psychiatric principles, rather than the legal test under Section 22. |
| Main Focus | Focuses on the person’s capacity to understand the nature of the act or that the act was wrong or contrary to law. | Focuses on whether the person suffers from a recognised mental illness or mental disorder. |
| Time of Assessment | The crucial point is the person’s mental condition “at the time of doing it.” | A medical condition may exist before, during, or after the particular incident. |
| Mental Capacity | Requires the specific incapacity recognised by Section 22 because of unsoundness of mind. | A person may have a mental illness while still retaining substantial understanding and decision-making capacity. |
| Total Loss of Understanding | The traditional description often refers to a loss of the relevant cognitive capacity, but the precise statutory test is whether the person was “incapable of knowing” the nature of the act or that it was wrong/contrary to law. | Medical insanity does not necessarily mean complete or total loss of understanding. A person may be medically diagnosed with a disorder but still understand their actions. |
| Nature of Test | Legal test — whether the statutory requirements of Section 22 are satisfied. | Medical/clinical test — whether a mental condition exists and how it affects the person. |
| Who Determines It? | Ultimately determined by the court on the basis of the evidence and applicable legal standards. | Assessed by medical professionals, particularly psychiatrists and other qualified experts. |
| Role of Medical Evidence | Medical evidence can help the court understand the person’s mental condition, but the final legal determination belongs to the court. | Medical evidence is central to diagnosing and describing the mental condition. |
| Effect on Criminal Liability | If the requirements of Section 22 are established, the person receives the General Exception and the act is not treated as an offence under the provision. | Medical insanity by itself does not automatically remove criminal liability. |
| Does Mental Illness Automatically Qualify? | No. The existence of a mental illness alone is insufficient. The Section 22 incapacity must be established. | Medical diagnosis may establish that a person suffers from a particular mental condition, but it does not by itself satisfy the legal test. |
| Evidence | May be established through medical evidence, conduct, circumstances, surrounding facts and other relevant evidence. | Primarily established through clinical examination, psychiatric assessment, medical history and other medical evidence. |
| Criminal Defence | Can operate as a complete defence to criminal liability when the requirements of Section 22 are satisfied. | It is not, by itself, a complete criminal defence. |
| Example | A person suffering from a serious mental condition commits an act and, because of that condition, is incapable of understanding what the act is or that it is wrong or contrary to law at that moment. Section 22 may apply. | A person has a medically diagnosed mental disorder but understands the nature of the act and knows that it is wrong or contrary to law. Medical insanity alone would not automatically attract Section 22. |
| Core Question | “Did the person’s unsoundness of mind make him incapable of the understanding required by Section 22 when the act was committed?” | “Does the person have a medically recognised mental illness or disorder, and what is its clinical effect?” |
| Result | May result in protection from criminal liability if the statutory requirements are fulfilled. | Primarily results in a medical diagnosis or assessment, not automatic exemption from criminal liability. |
The Most Important Difference
The distinction can be remembered through two questions:
Medical Insanity: “Does this person have a mental illness or disorder?”
Legal Insanity: “Because of unsoundness of mind, was this person legally incapable of understanding the nature of the act or that it was wrong or contrary to law at the time of the act?”
Therefore, medical insanity is not the same as legal insanity.
Medical Insanity Does Not Automatically Mean Legal Insanity
A person may suffer from a medically recognised mental disorder and still be capable of understanding:
- what they are doing;
- the nature of their conduct; and
- that their conduct is wrong or contrary to law.
In such circumstances, the existence of the medical condition alone does not automatically bring the person within Section 22.
Conversely, where the evidence establishes the specific incapacity contemplated by Section 22 at the time of the act, the legal defence may apply.
Medical Evidence and Legal Insanity
Medical evidence can be very important evidence in determining whether Section 22 applies.
A psychiatrist or other medical expert may provide evidence concerning the person’s mental condition. However, the medical diagnosis itself does not decide the legal issue.
The court ultimately has to determine whether the requirements of Section 22 BNS are satisfied.
Thus:
Medical evidence → Helps establish the mental condition.
Court → Determines whether the legal requirements of Section 22 are satisfied.
Important Correction to “Total Loss of Cognitive Faculty”
It is better, for accurate legal notes, not to describe legal insanity simply as “total loss of cognitive faculty.”
The exact statutory test under Section 22 is whether, because of unsoundness of mind, the person was “incapable of knowing”:
- the nature of the act, or
- that the act was either wrong or contrary to law.
Therefore, your notes should focus on the statutory test of incapacity, rather than saying that every case of legal insanity requires a complete or total loss of all mental faculties.
Legal Insanity vs. Medical Insanity
Case: Surendra Mishra v. State of Jharkhand (2011)
The Supreme Court examined the concept of “unsoundness of mind” in relation to the insanity defence. The Court observed that the expression is not expressly defined in the IPC and is generally associated with mental disorder or insanity. However, the mere fact that a person suffers from a mental disorder does not, by itself, make that person free from criminal responsibility.
Judgment in Simple Words
The Supreme Court made an important distinction between medical insanity and legal insanity. A person may be medically diagnosed with a mental disorder, but this alone is not enough to obtain the benefit of the insanity defence.
To rely upon the defence, the accused has to establish legal insanity, meaning that the mental condition must have produced the kind of mental incapacity recognised by criminal law at the relevant time.
Therefore, a medical diagnosis of mental illness does not automatically result in exemption from criminal liability. The court must determine whether the accused actually satisfies the legal requirements of the insanity defence.
5. Types of Insanity Relevant to Section 22 BNS
Dementia Naturalis and Dementia Accidentalis are traditional terms used in criminal-law discussions to classify unsoundness of mind according to when the mental condition originated. The first refers to a condition associated with birth or early life, while the second refers to a condition that develops after birth.
Dementia Naturalis — Unsoundness of Mind Present From Birth
Dementia Naturalis is a traditional expression used for a condition of mental incapacity that is considered to have been present from birth or developed from the earliest stage of life.
In simple terms, it refers to a person whose mental incapacity is understood to be inherent or congenital, rather than something that arose because of a condition occurring later in life.
The classification is concerned primarily with the origin of the mental condition. It does not, by itself, establish whether the person is legally protected from criminal responsibility.
Dementia Naturalis Under Section 22 BNS
The fact that a person’s mental condition existed from birth does not automatically bring the person within Section 22.
The provision is concerned with the person’s actual mental capacity when the act was performed.
The relevant question is whether, because of the unsoundness of mind, the person was incapable of:
“knowing the nature of the act”
or incapable of knowing:
“that he is doing what is either wrong or contrary to law.”
Therefore, even where the condition is described as Dementia Naturalis, the requirements of Section 22 must independently be satisfied.
Core Principle
Dementia Naturalis explains the origin of the condition; Section 22 determines whether that condition resulted in the legally relevant incapacity.
Example of Dementia Naturalis
Consider a person who has suffered from a serious mental incapacity since birth. Later, the person performs an act which would ordinarily attract criminal liability.
If, at the precise time of that conduct, the person’s mental condition prevented them from understanding what they were doing or from recognising that the conduct was wrong or contrary to law, Section 22 may become applicable.
However, if the person was capable of understanding the nature and wrongfulness of the act at that particular time, the mere fact that the condition existed from birth would not be sufficient to obtain the benefit of Section 22.
Dementia Accidentalis — Unsoundness of Mind Acquired After Birth
Dementia Accidentalis is a traditional expression describing a condition of mental incapacity that arises after birth.
Under this classification, the person is not considered to have been affected by the condition from birth. Instead, the mental incapacity develops at some later point during the person’s life.
The condition may arise in connection with different circumstances affecting mental functioning, but the important distinction here is simply that it is acquired rather than congenital.
This terminology is a traditional legal classification and should not be confused with a modern psychiatric diagnosis.
Dementia Accidentalis Under Section 22 BNS
A person who develops unsoundness of mind after birth does not automatically receive the protection of Section 22.
The same statutory requirement applies: the person’s mental condition must have affected their capacity at the time of the act.
The court must therefore consider whether, because of the person’s unsoundness of mind, they were incapable of:
understanding the nature of the act
or
knowing that the act was wrong or contrary to law.
If the required incapacity is established, Section 22 may provide the benefit of the General Exception.
Example of Dementia Accidentalis
Suppose a person has normal mental functioning during the earlier part of life but subsequently develops a serious mental condition.
During a particular episode, the person’s condition becomes such that they cannot understand the nature of an act they are performing or cannot appreciate that the act is wrong or contrary to law.
If this incapacity existed at the time of the act and the requirements of Section 22 are satisfied, the person may claim the protection provided by the provision.
Does Either Type Automatically Provide a Defence?
No.
Neither Dementia Naturalis nor Dementia Accidentalis automatically provides immunity from criminal liability.
Their significance is limited to describing the origin of the mental condition.
For Section 22 to operate, the legally relevant mental incapacity must be established at the time of the act.
Thus, a person cannot claim the defence merely by saying:
“My condition existed from birth.”
Similarly, it is not enough to say:
“I developed a mental condition later in life.”
The crucial issue is the person’s capacity to understand the act at the relevant time.
Section 22 Focuses on the Time of the Act
The most important feature of Section 22 is that the relevant mental condition must be considered at the time the act was committed.
A person may have experienced mental illness in the past or may develop a mental condition later. Neither fact alone determines the applicability of the defence.
The legal inquiry is directed towards the person’s mental capacity when the particular conduct occurred.
This is why the statutory words:
“at the time of doing it”
are particularly significant.
Both Types May Come Within Section 22
Both traditional categories can potentially be relevant to Section 22.
A person with Dementia Naturalis may qualify if the statutory incapacity existed at the time of the act.
Likewise, a person with Dementia Accidentalis may qualify if the acquired condition produced the required incapacity at the time of the act.
Thus, the distinction between the two categories does not determine the availability of the defence by itself.
Dementia Naturalis vs Dementia Accidentalis
| Basis | Dementia Naturalis | Dementia Accidentalis |
|---|---|---|
| Basic meaning | Traditional term for mental incapacity associated with birth or early life | Traditional term for mental incapacity that develops after birth |
| Origin | Congenital or present from the beginning of life | Acquired during the person’s lifetime |
| When it begins | From birth or earliest development | At a later stage of life |
| Nature of classification | Based on the origin of the mental condition | Based on the later development of the mental condition |
| Automatic Section 22 defence? | No | No |
| Importance under Section 22 | The condition must produce the legally relevant incapacity at the time of the act | The condition must produce the legally relevant incapacity at the time of the act |
| Relevant time | Time of commission of the act | Time of commission of the act |
| Legal test | Whether the person was incapable of the understanding specified in Section 22 | Same legal test |
| Effect if Section 22 is satisfied | Protection under the General Exception may be available | Protection under the General Exception may be available |
6. Special Mental States Relevant to Section 22
Irresistible Impulse
Irresistible impulse refers to a situation where a person claims that, although they may have understood what they were doing, they were unable to control or resist the impulse to perform the act.
The difficulty with treating irresistible impulse as an independent defence is that a person may experience a strong urge to do something without necessarily suffering from the legal incapacity contemplated by Section 22 BNS. If every uncontrollable or difficult-to-resist impulse were accepted as a defence, almost every person could potentially argue that their conduct was beyond their control.
Therefore, mere loss of self-control or inability to resist an impulse is not, by itself, sufficient to establish unsoundness of mind under Section 22.
Irresistible Impulse and Section 22 BNS
Section 22 is concerned with a person’s capacity to understand the nature of the act or to know that the act is wrong or contrary to law.
Accordingly, an irresistible impulse becomes relevant only where the underlying mental condition is so serious that it satisfies the legal test of unsoundness of mind.
In simple terms:
Mere inability to control an impulse ≠ legal insanity.
The person must satisfy the statutory requirements of Section 22.
Loss of Control vs Loss of Cognition
This distinction is important.
Loss of control means that a person may understand what they are doing but claims that they could not stop themselves.
Loss of cognition concerns the person’s ability to understand the nature of the act or to recognise its wrongfulness or illegality.
Section 22 primarily focuses on the cognitive incapacity recognised by the provision, rather than merely on an inability to control one’s behaviour.
Therefore, irresistible impulse should not be treated as an independent defence merely because the accused says that the impulse was extremely strong.
Somnambulism
Somnambulism, commonly known as sleepwalking, is a condition in which a person may perform physical or apparently purposeful acts while remaining in a state of sleep or incomplete consciousness.
During such a state, the person’s normal awareness and conscious control may be significantly impaired. The person may therefore perform an act without having the ordinary level of conscious understanding associated with waking behaviour.
Somnambulism and Section 22 BNS
Somnambulism may become relevant to Section 22 where the person’s condition results in the kind of mental incapacity contemplated by the provision.
The crucial question is not simply whether the person was sleepwalking. The court would have to consider whether, at the time of the act, the person’s condition made them incapable of knowing the nature of what they were doing or incapable of knowing that the act was wrong or contrary to law.
Thus, the relevant issue is the mental state of the accused when the act occurred.
Example
Suppose a person is sleepwalking and, while in that state, performs an act that would ordinarily amount to a criminal offence. If the evidence establishes that the person was genuinely unconscious or lacked the required understanding during the incident, the person’s mental state may become relevant to the defence.
The court would examine the surrounding circumstances and evidence before determining whether the requirements of Section 22 are actually satisfied.
Irresistible Impulse vs Somnambulism
| Basis | Irresistible Impulse | Somnambulism |
|---|---|---|
| Meaning | An alleged inability to resist or control an impulse | A state commonly associated with sleepwalking |
| Main issue | Lack of behavioural control | Lack of normal conscious awareness |
| Mental state | The person may still understand the act but claims inability to control it | Conscious awareness may be substantially absent or impaired |
| Section 22 | Mere loss of control is not sufficient | May be relevant if the required legal incapacity is established |
| Key consideration | Whether the underlying mental condition satisfies the statutory test | Whether the person lacked the legally required understanding at the time |
| Automatic defence? | No | No |
| Important principle | Strong impulse alone does not establish legal insanity | Sleepwalking alone does not automatically establish legal insanity |
7. Important Case Laws on Section 22 BNS — Unsoundness of Mind
(A) Cognitive Faculty of Mind
Case: Dahyabhai Chhaganbhai Thakker v. State of Gujarat (1964)
The Supreme Court clarified that merely showing that an accused suffers from a mental disorder is not enough to establish legal insanity. The mental condition must be so serious that it interferes with the person’s capacity to understand the nature of the act or to realise that the act is wrong or prohibited by law.
In other words, the court must look beyond the existence of a mental illness and determine whether that condition actually affected the accused’s ability to comprehend the act and its legal or moral character at the relevant time.
Judgment in Simple Words
The Court’s principle can be understood by saying that legal insanity concerns a person’s inability to exercise the necessary mental understanding, rather than simply the fact that the person has a mental illness.
Therefore, while applying the principle now contained in Section 22 BNS, the important consideration is the accused’s mental capacity when the act was committed.
(B) Correlation of Illness with the Offence
Case: Devidas Loka Rathod v. State of Maharashtra (2018)
In this case, the accused relied upon unsoundness of mind as a defence. The Supreme Court examined the available medical evidence along with the circumstances surrounding the incident to determine whether his mental condition had a relevant connection with the alleged conduct.
Judgment in Simple Words
The Supreme Court observed that while considering a plea of insanity, the court should take into account factors such as the nature of the mental condition, the treatment received by the accused, the medical history and whether the illness had a connection with the accused’s behaviour at the time of the incident.
The Court found that the evidence relating to the accused’s mental condition was significant enough to support the plea of insanity and accordingly extended the benefit of the relevant legal exception.
Core Principle
Simply proving that a person suffers from a mental illness is not sufficient; the court must consider whether that illness affected the person’s mental capacity in connection with the act at the relevant time.
This distinction helps explain why medical insanity and legal insanity are separate concepts.
(C) Wild Beast Test
Case: R. v. Arnold (1724)
The Wild Beast Test is an early approach to determining criminal responsibility on the ground of insanity. In R. v. Arnold, Justice Tracy stated that an accused should not be held criminally responsible where, because of mental incapacity, he was unable to understand the difference between right and wrong or was incapable of understanding the nature of what he was doing.
The principle was applied even where the alleged offence was extremely serious. The focus was on whether the accused possessed the mental understanding necessary to appreciate the character and wrongfulness of his conduct.
Judgment in Simple Words
The basic principle of the judgment was that a person who, because of insanity, cannot distinguish between good and evil or cannot understand the nature of his conduct should not be held criminally responsible for that conduct.
Thus, the seriousness of the offence alone was not sufficient to impose criminal responsibility where the required mental understanding was absent.
(D) Durham Rule
Case: Durham v. United States (1954)
The Durham Rule, also known as the “product test,” adopted a broader approach to insanity. Under this approach, an accused could not be held criminally responsible where the criminal act was the result or product of a mental disease or mental defect existing at the relevant time.
The focus therefore shifted from simply asking whether the accused could distinguish right from wrong to examining whether the mental disease or defect caused the criminal conduct.
Judgment in Simple Words
The basic principle was that if the unlawful act resulted from a mental disease or defect, the accused could not be convicted on that basis of criminal responsibility.
Therefore, the Durham Rule concentrated on the causal connection between the mental disorder and the criminal act rather than only examining the person’s ability to distinguish right from wrong.
8. Burden of Proof Under Section 22 BNS — Unsoundness of Mind
Meaning of Burden of Proof
Burden of proof means the responsibility of establishing a particular fact before the court. In a criminal case involving Section 22 BNS, the question is whether the accused can claim the General Exception of unsoundness of mind.
The prosecution has the primary responsibility of proving that the accused committed the offence and that the ingredients of the offence are established. However, when the accused relies upon Section 22, the accused also has a burden relating to the General Exception.
Burden on the Prosecution
The prosecution must first establish the commission of the offence by the accused in accordance with criminal law.
The prosecution cannot simply rely on the fact that the accused has a history of mental illness and then assume that the accused is legally insane. Similarly, the prosecution must prove the ingredients of the offence independently of the insanity defence.
The basic principle is:
The prosecution must establish the offence alleged against the accused.
Burden on the Accused
When an accused claims the benefit of Section 22, the accused has to bring evidence showing that the requirements of the General Exception are applicable.
The accused’s case is essentially that:
At the time of doing the act, because of unsoundness of mind, he was incapable of knowing the nature of the act or that what he was doing was wrong or contrary to law.
Therefore, the accused has to establish the factual basis for claiming the protection of Section 22.
Standard of Proof for the Accused
The burden placed upon the accused in establishing a General Exception is not the same as the prosecution’s burden of proving the offence beyond reasonable doubt.
The accused generally has to establish the existence of the circumstances bringing the case within the General Exception on the preponderance of probabilities.
In simple words, the accused does not ordinarily have to prove the defence with absolute certainty. It is sufficient if the evidence makes the existence of the circumstances supporting the exception more probable than not.
What Must Be Established for Section 22
For the defence of unsoundness of mind, the relevant issue is whether the accused’s mental condition satisfied the statutory test at the time of the act.
The evidence should therefore be directed towards showing that, because of unsoundness of mind, the accused was incapable of:
knowing the nature of the act
or
knowing that the act was wrong or contrary to law.
The mere existence of a mental illness is not enough.
Legal Insanity and Burden of Proof
The accused must establish legal insanity, not merely medical insanity.
A medical diagnosis may be relevant evidence, but the court ultimately has to determine whether the accused satisfied the legal requirements of Section 22.
For example, a person may have a medically recognised mental disorder but still understand:
“I know what I am doing, and I know that it is wrong.”
In such a situation, the mere existence of the disorder would not necessarily establish the Section 22 defence.
Relevant Time — Time of the Act
The burden relating to Section 22 primarily concerns the accused’s mental condition at the time when the act was committed.
Evidence of the accused’s condition before or after the incident can be relevant because it may help the court understand the person’s mental state at the relevant time.
However, the ultimate question remains:
What was the accused’s mental capacity when the act was committed?
Medical Evidence and Burden of Proof
Medical evidence can play an important role in an insanity defence.
Medical records, psychiatric treatment, expert opinion, previous history of mental illness and other medical material may assist the court.
However, medical evidence does not automatically establish legal insanity.
The court must connect the medical condition with the legal test contained in Section 22.
Thus:
Medical evidence → Helps establish the mental condition.
Legal test → Determines whether Section 22 applies.
Evidence of Conduct and Surrounding Circumstances
The court may also consider the accused’s conduct before, during and after the incident.
For example, circumstances may include the accused’s behaviour, statements, actions, ability to understand the situation and other surrounding facts.
Such evidence may help the court determine whether the accused possessed the required understanding at the relevant time.
Therefore, Section 22 is not decided solely on the basis of a medical certificate or diagnosis.
Burden Does Not Mean Absolute Proof
The accused is not required to establish the defence with mathematical certainty.
The purpose of the burden relating to the General Exception is to place before the court sufficient material from which it can reasonably conclude that the requirements of the exception are satisfied.
If the evidence makes the plea of unsoundness of mind sufficiently probable, the court must consider its effect in accordance with the rules governing General Exceptions.
Presumption of Sanity
Criminal law generally proceeds on the assumption that a person is sane and capable of understanding the nature and consequences of their conduct, unless the contrary is established in accordance with law.
Therefore, when an accused relies on Section 22, the plea of unsoundness of mind has to be supported by evidence.
However, the prosecution still carries the fundamental burden of establishing the offence charged against the accused.
Section 22 and Reasonable Doubt
The concepts of burden of proof and reasonable doubt should not be confused.
The prosecution’s case must satisfy the criminal standard applicable to proof of the offence.
The accused’s burden in establishing a General Exception is comparatively lighter. The accused generally needs to establish the exception on the preponderance of probabilities.
Once the evidence supporting the exception is sufficiently established, the court must consider whether the prosecution has nevertheless proved the offence in accordance with the applicable criminal standard.
Simple Example
Suppose A is accused of causing the death of B.
A claims the benefit of Section 22, stating that because of unsoundness of mind, at the time of the incident he was incapable of understanding the nature of his act or that it was wrong or contrary to law.
A may rely upon medical records, expert evidence, previous treatment, conduct surrounding the incident and other relevant circumstances.
The court will then examine whether the evidence establishes the requirements of Section 22.
The mere statement:
“I suffer from a mental illness”
would not, by itself, be sufficient.
The relevant question is:
Did the unsoundness of mind cause the legally relevant incapacity at the time of the act?
Burden of Proof — Easy Comparison
| Aspect | Prosecution | Accused claiming Section 22 |
|---|---|---|
| Primary role | Prove the offence | Establish the General Exception |
| What must be shown? | Ingredients of the offence | Requirements of unsoundness of mind under Section 22 |
| Relevant mental issue | Criminal liability for the offence | Legal incapacity caused by unsoundness of mind |
| Relevant time | Commission of the offence | Time of the act |
| Medical evidence | May be relevant where necessary | Can support the insanity defence |
| Standard | Criminal standard applicable to prosecution | Generally preponderance of probabilities for the General Exception |
| Mental illness alone? | Not sufficient to decide Section 22 | Not sufficient to establish Section 22 |
| Final question | Has the offence been proved? | Has the statutory exception been established? |
FAQs on Section 22 BNS — Unsoundness of Mind
1. Does every person suffering from mental illness get protection under Section 22 BNS?
No. The mere presence of a mental illness or psychological disorder does not automatically exempt a person from criminal liability. Section 22 requires the accused to satisfy the legal test of unsoundness of mind. The important consideration is whether, because of the unsoundness of mind, the person lacked the required understanding at the time of committing the act.
2. Why is the time of the offence important under Section 22?
Section 22 specifically refers to the person’s condition “at the time of doing it.” Therefore, the court primarily examines the accused’s mental capacity when the particular act was committed.
A history of mental illness before the incident or a mental condition developing after the incident may be relevant evidence, but neither fact alone establishes the defence. The crucial issue is the accused’s mental capacity at the relevant time.
3. What is the difference between legal insanity and medical insanity?
Medical insanity is concerned with the existence and nature of a mental disorder from a medical perspective. Legal insanity, on the other hand, is concerned with whether the person’s mental condition satisfies the requirements laid down by criminal law.
Therefore, a person may be medically diagnosed with a mental disorder but still remain criminally responsible if they possessed the understanding required by Section 22.
Medical illness alone does not automatically establish legal insanity.
4. How are irresistible impulse and somnambulism relevant to Section 22?
Irresistible impulse refers to a claimed inability to resist or control a powerful impulse. Mere loss of behavioural control, however, does not automatically satisfy Section 22. The underlying mental condition must produce the legally recognised incapacity required by the provision.
Somnambulism, commonly known as sleepwalking, involves performing acts during a sleep-related state with impaired conscious awareness. It may become relevant to Section 22 if the evidence establishes that the person’s mental state at the time of the act resulted in the incapacity contemplated by the provision.
5. Which important legal tests and cases help explain the defence of insanity?
The Wild Beast Test, associated with R. v. Arnold, represents an early approach focusing on the person’s ability to understand the nature of the act and distinguish right from wrong.
The Durham Rule, developed in Durham v. United States, focuses on whether the criminal act was the product of a mental disease or defect.
Important Indian decisions include Dahyabhai Chhaganbhai Thakker v. State of Gujarat on cognitive capacity, Surendra Mishra v. State of Jharkhand on the distinction between medical and legal insanity, and Devidas Loka Rathod v. State of Maharashtra on the relevance of the nature of illness, medical evidence and its connection with the conduct.