LEGAL PRINCIPLE: CRIMINAL LAW — Defences — Insanity — Question of Fact
PRINCIPLE STATEMENT
Insanity is primarily a question of fact to be determined by the trial court, taking into consideration all admissible evidence, including medical evidence, the nature of the killing, conduct before, at, and after the killing, and any past history of mental abnormality.
RATIO DECIDENDI (SOURCE)
Per Iguh, JSC, in Ani v. State (2002) NLC-3152001(SC) at p. 11; Paras E–A.
"The law is settled that insanity is primarily a question of fact to be determined by the trial court which ought to take into consideration each and every admissible piece of evidence tendered before it, including medical evidence, where available, together with the whole of the facts and surrounding circumstances of the case, particularly such vital facts like the nature of the killing, the conduct of the accused before, at and immediately after the killing and any past history of mental abnormality of the accused."
EXPLANATION / SCOPE
Insanity is a factual determination. The trial court considers all admissible evidence. Factors include medical evidence, nature of the killing, conduct before, during, and after, and past mental abnormality. The principle gives the trial court discretion. The appellate court will defer to factual findings unless perverse. The court must evaluate the totality of circumstances. Medical evidence is important but not conclusive. The rule applies to all insanity defences. The court must consider the accused’s behaviour and statements. The trial judge’s assessment is entitled to weight. The appellate court will not substitute its own view lightly.
