ABSTRACT
It is a general defence and may be pleaded as a defence to any crime requiring mens rea (including murder), whether tried on indictment in the Crown Court or summarily in the magistrates’ court (Horseferry Road Magistrates’ Court, ex parte K [1996] 3 All ER 719). However, it is not, apparently, a defence to crimes of strict liability (see Chapter 4). In DPP v H [1997] 1 WLR 1406, the High Court held that insanity was no defence to a charge of driving with excess alcohol contrary to s 5 of the Road Traffi c Act 1988. Medical evidence that D was suffering manic depressive psychosis with symptoms of distorted judgment and impaired sense of time and of morals at the time of the offence was, therefore, irrelevant.
