4 The excusable defences

Infancy — absolute immunity below a stated age; qualified immunity for a range above it, where the child's understanding is examined. In Nepal the National Penal Code 2074 sets the threshold and provides for reformative rather than punitive measures for children. Insanity — the test is legal, not medical: whether the accused, at the time of the act, was incapable of knowing the nature of the act or that it was wrong. A mental illness that does not destroy that capacity is not a complete defence. Mistake — a mistake of fact may excuse; a mistake of law generally does not, because everyone is presumed to know the law. Intoxication — involuntary intoxication may excuse; voluntary intoxication ordinarily aggravates or at best leaves liability intact, since the accused chose to drink.