Criminal law serves as a vital mechanism for maintaining societal order, holding individuals accountable for actions deemed to be in violation of established norms. However, certain circumstances may impair a person’s mental capacity to the extent that they may not be fully responsible for their criminal actions. The relationship between criminal law and mental health is captured by legal defenses such as insanity and diminished responsibility. In Nigeria, these defenses are rooted in both statutory law and judicial precedents.
The Insanity Defense in Nigeria – criminal law and mental health
Legal Framework:
The insanity defense is encapsulated under Section 28 of the Criminal Code Act (applicable in Southern Nigeria) and Section 51 of the Penal Code Act (applicable in Northern Nigeria). Both provisions mirror the principles set out in the M’Naghten Rules, a common law standard developed by British courts in the 19th century.
Section 28 of the Criminal Code Act provides:
“A person is not criminally responsible for an act or omission if at the time of doing the act or making the omission he is in such a state of mental disease or natural mental infirmity as to deprive him of capacity to understand what he is doing, or of capacity to control his actions, or of capacity to know that he ought not to do the act or make the omission.”
Section 51 of the Penal Code similarly holds:
“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.”
Judicial Interpretation:
Nigerian courts have consistently applied the M’Naghten Rules, which set out two key elements for establishing an insanity defense:
- Cognitive Incapacity: The accused must be shown to have been incapable of understanding the nature of their actions at the time of the offense.
- Moral Incapacity: Alternatively, the accused may be deemed insane if they were unable to distinguish between right and wrong in relation to the act committed.
In Aro v. The State (1981), the Supreme Court of Nigeria emphasized that for the defense of insanity to succeed, the defendant must provide sufficient evidence to convince the court that they suffered from a mental disorder at the time of the offense. This evidence typically includes psychiatric evaluations, medical reports, and testimonies from family or experts who observed the individual’s behavior.
In the case of Udofia v. The State (1981), the court held that the defense of insanity could only be upheld if it could be proven that the accused was suffering from such mental illness that deprived them of the capacity to appreciate the nature or consequences of their actions.
Burden of Proof:
While the presumption in Nigerian criminal law is that all persons are of sound mind and capable of being held responsible for their actions, the burden of proving insanity rests on the defendant. The standard of proof is on the “balance of probabilities,” unlike the prosecution’s burden, which is “beyond reasonable doubt.”
Diminished Responsibility
Diminished responsibility is a partial defense to murder in Nigeria, and it operates to reduce what would otherwise be a charge of murder to manslaughter. This defense applies when the mental state of the accused, though impaired, does not meet the full criteria for legal insanity but still significantly affects their responsibility for the crime.
Statutory Provision:
The defense of diminished responsibility is provided under Section 27 of the Criminal Code Act, which states:
“A person whose mind, at the time of his doing or omitting to do an act, is affected by disease or infirmity to such an extent as to deprive him of his mental capacity to form an intent, or to control his actions, or to understand the consequences of his actions, is not criminally responsible for his act or omission.”
The Penal Code Act does not explicitly mention diminished responsibility, but the concept is implied in various judicial interpretations and the flexibility provided under the Code’s sentencing framework.
Judicial Interpretation:
In R v. Ogor (1961), the court held that diminished responsibility could apply when the defendant’s mental capacity was substantially impaired, but they were not completely devoid of the ability to know what they were doing or to appreciate the wrongfulness of their act. In such cases, the defendant may be convicted of manslaughter rather than murder, as they are seen to have some degree of responsibility, albeit reduced.
Sunday Udofia v. The State (1984) is another case that exemplifies the application of diminished responsibility. The court reduced a murder charge to manslaughter after accepting evidence that the accused suffered from a mental condition that affected his capacity to form intent at the time of the killing.
Burden of Proof:
Like the insanity defense, the burden of proving diminished responsibility lies with the defendant. However, once the defense is raised, the prosecution must rebut it with sufficient evidence. The standard of proof is the same as for insanity: the defendant must prove diminished responsibility on a balance of probabilities.
Relationship between Insanity and Diminished Responsibility
While both insanity and diminished responsibility are mental health defenses, they differ significantly in their scope and legal consequences.
- Insanity is a complete defense, leading to an acquittal if successful, but it also often results in the accused being committed to a psychiatric institution for treatment, as provided under Section 230 of the Criminal Procedure Act. The court may order detention at the President’s or Governor’s pleasure, depending on whether the crime was federal or state-related.
- Diminished responsibility, on the other hand, is a partial defense that reduces the severity of the crime, typically from murder to manslaughter, but does not absolve the defendant of all criminal liability. The defendant may still face imprisonment but with a lighter sentence than for murder.
Related: Understanding the Concept of Self-Defence under Nigerian Criminal Law
Challenges and Criticisms
The application of these defenses in Nigeria faces several challenges:
- Stigma and Public Perception: Mental illness remains stigmatized in many parts of Nigeria, which may influence the willingness of families to provide evidence or the willingness of judges to accept mental health defenses.
- Lack of Psychiatric Resources: Nigeria’s healthcare system, particularly in the area of mental health, is underfunded and lacks the resources to provide comprehensive psychiatric evaluations for defendants. This limits the ability of courts to obtain reliable evidence in support of mental health defenses.
- Inconsistent Application by Courts: While the statutory provisions are clear, judicial interpretation and application can vary. Some courts have been reluctant to fully embrace these defenses, particularly in cases involving violent crimes, for fear of allowing dangerous individuals to escape punishment.
Conclusion
The insanity defense and diminished responsibility play crucial roles in aligning Nigeria’s criminal justice system with principles of fairness and equity. These defenses recognize that individuals suffering from mental illnesses may not possess the full capacity to appreciate the nature or wrongness of their actions. However, their application remains complex, as it involves balancing the need for justice for victims with compassion for the mentally ill. Continued judicial engagement and reform in the area of mental health are essential to ensure these defenses serve their intended purpose within the Nigerian legal framework.