A person is not criminally responsible for an act or omission if he does or omits to do the act under any of the following circumstances‐
(1) in execution of the law;
(2) in obedience of the order of a competent authority which he is bound by law to obey, unless the order is manifestly unlawful;
(3) when the act is reasonably necessary in order to resist actual and unlawful violence threatened to him, or to another person in his presence;
(4) when he does or omits to do the act in order to save himself from immediate death or grievous harm threatened to be inflicted upon him by some person actually present and in a position to execute the threats, and believing himself to be unable otherwise to escape the carrying of the threats into execution,
but this protection does not extend to an act or omission which would constitute an offence punishable with death, or an offence of which grievous harm to the person of another, or an intention to cause such harm, is an element, nor to a person who has by entering into an unlawful association or conspiracy rendered himself liable to have such threats made to him.
Whether an order is or is not manifestly unlawful is a question of law.
Section 32 of the Criminal Code Act in Nigeria