LEGAL PRINCIPLE: CRIMINAL LAW — Defences — Insanity — Absence of Motive
PRINCIPLE STATEMENT
Mere absence of any evidence of motive for a crime is not sufficient ground upon which to infer insanity.
RATIO DECIDENDI (SOURCE)
Per Katsina-Alu, JSC, in Ani v. State (2002) NLC-3152001(SC) at p. 5; Paras A–B.
"Mere absence of any evidence of motive for a crime is not sufficient ground upon which to infer insanity. See R. v. Ashigifuwo (supra)."
EXPLANATION / SCOPE
Lack of motive alone does not establish insanity. The accused must adduce positive evidence of mental disease or infirmity. Motive is not an essential element of a crime. The principle prevents the defence from relying on absence of motive to prove insanity. The court requires evidence of the accused’s mental state. The rule applies to all criminal trials. The accused cannot substitute lack of motive for proof of insanity. The prosecution need not prove motive. The court will consider all circumstances, but absence of motive is not determinative. The principle ensures that insanity is proved by direct evidence, not speculation.
