LEGAL PRINCIPLE: CRIMINAL LAW — Defences — Insanity — Burden of Proof
PRINCIPLE STATEMENT
Where an accused pleads insanity, the onus is on him to produce evidence of insanity.
RATIO DECIDENDI (SOURCE)
Per Katsina-Alu, JSC, in Ani v. State (2002) NLC-3152001(SC) at p. 2; Paras B–C.
"Where an accused pleads insanity, the onus is on him to produce evidence of insanity. In the instant case the onus was on the appellant to establish insanity. See Udofia v. The State (1981) 11-12 SC 49."
EXPLANATION / SCOPE
The accused bears the burden of proving insanity as a defence. The prosecution is not required to disprove insanity. The burden is on the balance of probabilities (civil standard). The principle is based on the presumption of sanity. The accused must adduce evidence of mental disease or infirmity. The court will consider medical evidence and surrounding circumstances. The rule applies to all criminal trials. The accused cannot rely on mere assertion. The burden includes proving that the insanity affected capacity. The principle ensures that the defence is not raised frivolously.
