Cannabis, Voices, and the Machete Killing
Emeka, 29, drinks eight bottles of beer and smokes cannabis at a party. At 1 a.m., he returns home, accuses his mother of poisoning his food, and attacks her with a machete, inflicting 14 cuts. She dies. His mother, 61, had prepared the meal. A neighbour calls the police at 1:20 a.m. Emeka tells police he heard 'three voices' ordering him to kill a witch, but he remembers hiding the machete and washing blood from his hands. Two psychiatrists agree he has no underlying psychosis; one says he had 'acute cannabis intoxication with transient hallucinations,' the other says he knew the nature of his act but could not control his urge. He had no prior psychiatric history. He is charged with murder. The prosecution argues voluntary intoxication is no defence.
1. Can Emeka successfully raise insanity? Apply the M'Naghten-style test and explain who bears the burden.
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Insanity requires a disease of the mind that causes a defect of reason, so that the accused did not know the nature and quality of his act or did not know that it was wrong. Emeka's psychiatrists agree there is no underlying psychosis. The transient hallucinations from cannabis are not, without more, a disease of the mind. His conduct after the attack undermines the defence: he hid the machete and washed blood from his hands, which shows he knew what he had done and that it was wrong. His accusation that his mother poisoned him may explain motive or delusion, but it does not establish that he lacked knowledge of the act.
The burden is on the defence to prove insanity on the balance of probabilities; the prosecution need not disprove it beyond reasonable doubt once the issue is raised. On these facts, insanity is likely to fail. The court may convict of murder unless intoxication or diminished responsibility is accepted under the applicable law.
2. If insanity fails, can voluntary intoxication reduce murder to manslaughter? Distinguish specific from basic intent.
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Voluntary intoxication is not a general defence. For crimes of basic intent, such as manslaughter or assault, intoxication is no excuse, because getting drunk is itself reckless. For crimes of specific intent, such as murder, evidence that the accused was so intoxicated that he could not form the intent to kill or cause grievous bodily harm may reduce the offence to manslaughter.
Emeka's evidence could support that argument: eight beers plus cannabis, voices, and a claim that he did not know what he was doing. But the prosecution can counter with his motive (the poisoning accusation), the sustained nature of the attack (14 cuts), and his concealment of the machete and washing of blood. Those facts suggest he retained purpose and awareness.
The court will therefore ask whether the intoxication was severe enough to negate the specific intent for murder. If yes, conviction for manslaughter is possible; if no, murder stands. The burden of laying a foundation for intoxication is on the defence, but once raised, the prosecution must still prove the required intent beyond reasonable doubt.