INSANITY UNDER THE NIGERIAN LAW
Historically, the case of Daniel M’Naghten decided in 1843 marked a turning point in the history of using “insanity” as a defence. The English case formulated the following criteria as the basis of the insanity plea;
i. That everyone is presumed sane until the contrary is proved
ii. That it is defence for the accused to show that he is labouring such a defect of reason, due to disease of the mind as either not to know the nature or quality of his act or if he did know, not to know that he was doing wrong
iii. That if a man commits a criminal act under insane delusion, he is under the same degree of responsibility as he would have been on the facts as he imagined them to be.
Nigeria as a Common Law jurisdiction, has adopted this position with necessary modifications to suit local circumstances. Under Nigerian law, everyone is presumed sane and rational until it is proven otherwise.
Sections 27, 43, and 284 of the Criminal Code, Penal Code and The Administration of Criminal Justice Act, (ACJA), 2015 respectively, make provision for this legal presumption. The two Codes essential to the Nigerian criminal justice system are:
a. The Criminal Code
The Criminal Code is used in the Southern part of Nigeria and Sections 27 and 28 of the Criminal Code lay out the provisions for insanity. Section 27 of the Code states the obvious and serves as a preamble to the defence of insanity in the following words:
“Every person is presumed to be of sound mind and to have been of sound mind at any time which comes in question until the contrary is proved”.
Section 28 of the Code, which establishes the insanity plea, stipulates as follows:
“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 28 of the Criminal Code was given judicial recognition by the Supreme Court in the case of Madjemu V State[3]. The brief fact of the case is that;
The Appellant was arraigned for the offence of murder of his wife. He pleaded not guilty to the charge. At the conclusion of the trial, the trial Court found him guilty as charged and sentenced him to death by hanging. He appealed to the Court of Appeal which dismissed the appeal. He further appealed to the Supreme Court which also dismissed the appeal and stated that to establish the defence of insanity, recourse could be had to the following relevant facts namely:
- evidence as to past history of the accused person;
- evidence as to the conduct of the accused immediately preceding the killing of the deceased;
- evidence from prison officials who had custody of the accused person before and during his trial;
- evidence of medical officers who examined the accused;
- evidence of relatives about the general behaviour of the accused person and the reputation he enjoyed for sanity or insanity in the neighbourhood and
- evidence showing that insanity runs in the family history of the accused;
and such other facts which will help the trial court come to the conclusion that the burden of proof placed by law on the defence has been dismissed but in this case, the Appellant has failed to do so.
b. Penal Code
The Penal Code replaces the Criminal Code in the Northern part of Nigeria. The following provision is made about insanity by the Code. According to Section 51 of the Penal Code:
“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 he is doing what is either wrong or contrary to law”.
In the unreported case of State V Shittu,[4] the accused killed his mother by repeatedly beating her in the skull with a shovel, ostensibly in an effort to convert her to Islam. The trial judge, Gbadeyan J., found the defendant not guilty on the basis of insanity and made several comments, including:
“If in his lunacy the accused thought he was reciprocating the faithfulness of his loving mother or was correcting her by using a shovel to hit her several times believing up till his trial that she was loving, then it is crystal clear that he was denied by the unsoundness of mind the capacity to understand the nature of his act”.
c. Administration of Criminal Justice Act, (ACJA) 2015
Pursuant to Section 284 ACJA, Where the defendant appears to be of unsound mind at the time of any remand or similar pre-trial proceedings before a court, and the issue of the state of soundness of mind of the defendant is in question, with regards to a defence to the main offence for which he is arrested relating to insanity or intoxication, the court shall proceed to deal with the defendant in accordance with sections 278 to 291 of this Act and shall not make any finding of fact in relation to such defence that the defendant is open to plead at his trial for the offence.