General Defenses in Criminal Trials.

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Attempts and conspiracies are known as "inchoate" crimes. This is because the full actus reus of the principal offence had not been reached. However, as far as an attempt is concerned, the "full" actus reus of attempt must be there. The problem with these crimes rests primarily on the question of actus reus and not mens rea.

 

1. Insanity in Criminal Law

The defence of insanity is grounded on the principle that due to a mental condition, the accused lacked mens rea at the time of committing the offense. Section 12 of the Penal Code presumes every person to be of sound mind unless proven otherwise. However, section 13 provides that a person is absolved of criminal responsibility if it is reasonably shown that, at the time of the act or omission, they were incapable of understanding what they were doing or knowing that it was wrong.

The Tanzanian law on insanity is based on the precedent set in R v. Daniel M’Naghten (1843), 10 Cl & F 200. In this case, the accused was charged with the murder of Edward Drummond, whom he shot in the back. The defence presented evidence that the accused was not of sound mind during the act. Medical experts provided opinions based on prior examinations or observations during the trial. The accused was acquitted on the grounds of insanity. Following the case, the House of Lords sought judicial clarification on the legal threshold for insanity, culminating in what is now referred to as the M’Naghten Rules.

For the defence of insanity to succeed, three conditions must be satisfied:

1. The accused must be proven to have suffered from a disease of the mind at the time of the act or omission.
2. It must be shown that the accused did not understand the nature or quality of their actions.
3. Alternatively, if they understood the nature or quality of their actions, it must be demonstrated that they did not know it was wrong.

The mental disease must impair reasoning to such an extent that it renders the accused incapable of understanding the act or its consequences. Section 13 further clarifies that criminal liability is not excluded if the mental disease does not produce the effects required under this defence.

In Philip Musele v. R (EACA 622), the appellant, convicted of murdering his wife, argued that he was unaware of his actions at the time. A psychiatrist testified that the appellant believed his wife practiced witchcraft, justifying his actions in his mind. However, the court held that knowing an act is morally justified does not suffice for insanity; the accused must not know the act is legally wrong. The court found the evidence inadequate to establish insanity and dismissed the appeal.

The burden of proving insanity rests on the defence, requiring proof on a balance of probabilities, a higher standard than raising a reasonable doubt. This principle was upheld in Nyinge s/o Suwatu v. R (1959) EA 974.

Legally, the term "insane" differs from its medical use. It categorizes individuals who, due to a mental disease, lack mens rea or are unaware of the illegality of their actions. For example, in R v. Tomson s/o Msumali (1969) HCD n. 26, the accused, prone to epileptic fits, killed his father during an episode. Medical evidence showed he could not comprehend the nature of his act, leading the court to deliver a verdict of "guilty but insane."

Criticism of the M’Naghten Rules includes the following:

1. They rely on the outdated concept of partial insanity.
2. They focus solely on cognitive impairments, excluding emotional and volitional factors like irresistible impulses.
3. They are unclear on their application to cases of incomplete mental development, such as intellectual disabilities.
4. The burden of proof for insanity is higher than in typical criminal cases, requiring proof on a balance of probabilities rather than merely raising doubt.

2. Intoxication in Criminal Law

Intoxication, while not a defence in itself, may influence the determination of mens rea in criminal cases. The effects of intoxication, such as impairing perception, judgment, and self-control, can lead an individual to act in ways they would not if sober. In criminal law, intoxication is only considered a defence under the provisions of section 14 of the Penal Code. This section provides that intoxication absolves criminal responsibility if, at the time of the act or omission, the accused did not know what they were doing and:

(a) The intoxication was caused involuntarily, either through the malicious or negligent act of another person; or
(b) The accused, due to intoxication, was temporarily or permanently rendered insane at the time of the act or omission.

Lord Denning, in Attorney General for Northern Ireland v. Gallagher (1961) 45 Cr. App. R. 316, offered a detailed analysis of the effects of intoxication on criminal liability, emphasizing three primary impairments caused by alcohol or drugs:

1. A diminished ability to foresee or measure the consequences of one’s actions.
2. Impaired judgment regarding right and wrong, leading to actions that would not occur if sober.
3. Reduced self-control, making one more susceptible to provocation.

Section 14(4) of the Penal Code aligns with this reasoning, mandating that intoxication be considered when determining the presence or absence of mens rea. The law also recognizes intoxication caused by narcotics or drugs as equivalent to that caused by alcohol.

In Tanzania, as in British law, the courts have debated the distinction between voluntary and involuntary intoxication. In R v. Lipman (1970) QB 152, the British court expressed the view that the effects of intoxication, whether voluntary or involuntary, should not differ in assessing criminal liability. Tanzanian courts have echoed this sentiment. For instance, in R v. Stanislaus (1969) HCD n. 32, the accused, after heavy drinking, stabbed the deceased. His intoxicated state influenced the court's finding, leading to a conviction for the lesser offence of manslaughter.

Similarly, in R v. Danson (1967) HCD No. 71, the court considered the accused’s intoxication in determining the absence of premeditation, resulting in a manslaughter conviction rather than murder. These cases underscore the importance of assessing intoxication's impact on an accused's mental state when determining their culpability.

For additional clarity, review the following cases:

1. DPP v. Beard (1920) AC 479
2. R v. Magoma (1971) HCD 44

3. Defence of Person and Property in Criminal Law

The general principle is that the state holds the monopoly on the use of force. However, exceptions exist where individuals are permitted to use force for self-defence, the defence of another, or the defence of property. Section 18 of the Penal Code explicitly states that a person is not criminally liable for acts done in these forms of defence. Section 18A(1) provides further that no criminal liability arises when a person defends themselves, another person, or property (their own or under their lawful care) from unlawful acts of seizure, destruction, or violence.

In Manzi Mengi v. R (1964) EA 288, the accused successfully invoked self-defence. The deceased attacked the accused on his farm, firing arrows and threatening to kill him. After the deceased struck the accused and continued his aggression, the accused used a panga to defend himself, resulting in the deceased's death. Initially convicted of manslaughter due to excessive force, the appeal court held that lethal force was justified to save his life, overturning the conviction.

Similarly, in R v. Mohamed s/o Ndowe (1970) HCD n. 211, three watchmen defended their employer's property and their lives against a group of thieves, including the deceased. The court found that their use of force was necessary and proportional, acquitting them of murder.

Section 18B of the Penal Code places limits on these defences, requiring that the use of force be reasonable and proportional to the threat. In Saidi s/o Abdallah (1971) HCD n. 266, the accused responded to a slap with excessive violence, leading to their conviction for assault. The court emphasized that force must be proportional to the circumstances.

Section 18C outlines circumstances where self-defence extends to causing death. These include threats of death, grievous harm, or crimes such as rape, kidnapping, burglary, robbery, or arson that endanger life or property. In R v. Nyakalio (1970) HCD n. 344, a woman was acquitted after fatally attacking a man who attempted to rape her. The court recognized her right to defend her life and chastity.

The right to self-defence, however, does not apply to aggressors. In Selemani s/o Ussi (1963) EA 442, the accused stabbed and killed the deceased while being pursued for suspected theft. The court found that he was not in imminent danger of death and thus could not claim self-defence, upholding his murder conviction.

The practical application of these rights raises challenging questions:

1. Can a victim accurately assess the proportionality of their response in high-pressure situations?
2. When does the right to defence end if the aggressor retreats?
3. Can an initial aggressor ever invoke self-defence?

Additionally, jurisdictions differ on whether victims must retreat before using force. In Britain, such a duty exists, while in the USA, it does not. Tanzania has not explicitly addressed this issue, leaving room for further legal and scholarly discussion.

For further reading, consult:

1. Ilapala s/o Ibrahim v. R, 20 EACA 300
2. Mengi v. R (1964) EA 289
3. Marwa Robi v. R (1959) EA 660
4. Uganda v. Muherwa (1972) EA 44

4. Mistake of Fact, Law, and Bona Fide Claim of Right

Mistake of Fact
Section 11 of the Penal Code provides a defence for actions or omissions arising from an honest and reasonable mistake of fact. This defence is based on the absence of mens rea—the guilty mind required for criminal responsibility. For instance, in R v. Sultan Megiga (1969) HCD n. 33, the accused mistakenly believed he was attacking an animal when he threw a spear, fatally wounding a person. Since there was no intention to kill a human, the court held it was a mistake of fact, acquitting the accused of murder. However, a mistake of fact that does not negate mens rea offers no defence, as illustrated by a hypothetical case where a person smuggling an item mistakenly believes it is of a different kind but remains liable since both items are dutiable.

Mistake of Law
Ignorance of the law is not a defence, as outlined in Section 8 of the Penal Code. Even if an individual is unaware of a legal requirement, they are still culpable, as seen in Maulidi v. R (1970) HCD n. 346. The appellant, ignorant of employment laws, was convicted for failing to maintain employment records and pay the minimum wage.

Exceptions to Mistake of Law

1. When knowledge of the law is an element of the offence.
2. Bona Fide Claim of Right
   Section 9 of the Penal Code allows this defence if an offence is committed in the honest belief of a right, provided there is no intention to defraud. For example, in Salum Ibrahim v. R (1971) HCD n. 481, the accused reclaimed property he believed to be his and was acquitted of robbery due to his bona fide claim of right.

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Provocation
Section 202 of the Penal Code defines provocation as a wrongful act or insult capable of depriving an ordinary person of self-control, inducing them to commit an assault. For provocation to be a defence, the act must be grave and sudden, lead to a loss of self-control, and the retaliation must be proportional. Under Section 201, killing under provocation reduces the offence from murder to manslaughter, as in R v. Johali Ismail (1974) L.R.T n. 23.

Objective Test of Provocation
The standard of a reasonable person is applied, as shown in Bedder v. DPP (1954) 2 All E.R. 801, where the accused's physical characteristics were not considered relevant. However, for intoxicated individuals, the effect of alcohol on their state of mind is considered, as noted in R v. Damson Simbcungile (1967) HCD n. 71.

Cooling Time and Retaliation
Provocation must lead to immediate loss of control, and delayed retaliation negates the defence, as it indicates premeditation. The principle was emphasized in Kalume v. R (1954) E.A.C.A 201, where the accused's immediate reaction to discovering infidelity was deemed provocation.

Insults as Provocation
Insults generally do not constitute provocation unless recognized as such in the relevant community, as in R v. Mahamudu s/o Kibwana (1968) HCD n. 186. Mere annoyance, however, is insufficient, as established in R v. Alistahiki s/o Masumbuku (1967) HCD n. 343.

Last Straw Doctrine
This doctrine recognizes cumulative provocation, where a series of actions culminates in loss of self-control, as discussed in R v. Johali Ismail (1974) LRT n. 23.

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Other Defences
Minor defences include immaturity (Section 15), judicial privilege (Section 16), and compulsion or coercion (Sections 17 and 20). These should be studied in detail for a comprehensive understanding.