Abstract

Douglas Husak’s book is an intelligent, wide-ranging exploration of the legal principle ‘ignorance of law is no excuse’. This principle is one of the few pieces of legal doctrine known by many regular folks, along with the criminal standard of proof ‘beyond a reasonable doubt’. The traditional approach to the doctrine might be explained in this way: in some cases, ignorance of the law fails to excuse offenders from culpability because as a matter of policy we feel they ought to have known the law governing their behaviour. Placing upon citizens the responsibility to know the law is good policy because it may increase both knowledge of law (by inspiring persons considering questionable action to investigate legal rules, etc.) and law-abiding behaviour (by dissuading those who discover their possible act is illegal from acting). Although many believe the criminal law’s primary purpose is state-imposed backwards-looking ‘just deserts’ for moral wrongs, the law also serves to accomplish forward-looking aims such as enhancing moral agency and decreasing crime. From this perspective, the principle that ignorance of the law does not excuse contributes to rule of law and social order by encouraging awareness of legal rules. Husak’s position on ignorance of law is sometimes difficult to discern amongst the detailed critique and commentary on competing views that occupy most of the first 100 pages. In the end, Husak bucks a forward-looking account of the principle and concludes that ignorance of the law – or more exactly, ignorance of the law related to ignorance of the morality underpinning the law – ought to serve as an excuse to criminal guilt in most cases. Further, he claims ignorance of law ought to excuse in the same way that that ignorance of an important fact regarding one’s crime excuses. That he is mistaken regarding an important fact about his crime matters to a defendant’s blameworthiness – e.g. if the defendant kills in self-defence, mistaking the toy gun their victim is carrying with a real gun. A person who honestly believes they are in immediate danger from an armed aggressor is less than fully blameworthy for killing that aggressor even if they were mistaken about the threat. Similarly, knowledge or ignorance that some act is morally wrong clearly matters to moral blameworthiness, says Husak: other things being equal, a person who is ignorant of the moral wrongness of her act is less blameworthy than someone who is aware that what she is doing is wrong. Where ignorance of that an action violates a criminal law is related to ignorance regarding the morality of the act, a person is less than fully culpable.