In Rex v Bourke, an important case in South African criminal law, the Transvaal Provincial Division (TPD) held that, under Roman-Dutch law, drunkenness is, as a general rule, no defence to a crime, although it may be a reason for mitigation of punishment. If the drunkenness is not voluntary—that is, if not caused by an act of the accused—and results in rendering the accused unconscious of what he was doing, he would not be responsible in law for an act done while in such a state. If constant drunkenness has induced a state of mental disease rendering the accused unconscious of his act at the time, he is not responsible and can be declared insane. Where a special intention is necessary to constitute a particular offence, drunkenness might reduce the crime from a more serious to a less serio