Published online by Cambridge University Press: 02 January 2018
Theoretical discussion of the question of whether and under what circumstances ignorance of law should be a defence from criminal liability has had a peculiar history in Anglo-American law. Commentators have been more convinced that ignorance oflaw should generally not serve as a defence than they have been persuaded by any particular rationale in favor of this rule. When one argument is shown to be unsound, another emerges to take its place, preserving the conclusion intact; the weight of scholarly opinion does not shift to embrace the position that ignorance of law should typically be a defence from criminal liability.
1. In this respect, the controversy about whether ignorance of law should serve as a defence resembles the debate about punishment itself. Philosophers have differed radically about the justification of punishment, with no particular answer persuading a majority. Still, few philosophers have ever concluded that punishment is unjustified. 9. See the proposed distinction between mistakes about the ‘same law’ and mistakes about ‘other laws’ in Dressler, Joshua., Understanding Criminal Law (New York: Matthew Bender, 1987), pp 150–151Google Scholar; and the distinction between ‘mistakes that relate to the elements of a criminal offence’ and ‘mistakes that relate to the eistence and meaning of the criminal law governing the transaction’ in Kenneth Simons: ‘Mistake and Impossibility, Law and Fact, and Culpability,’ (1990) 81 Journal of criminal Law and Criminology, pp 447–517.
3. 210 NW 137 (1926).
4. Andrew Ashworth Principles of Criminal Law (Oxford: Clarendon Press, 1991) p 209.
5. A more complete account is provided in Douglas Husak and Andrew von Hirsch ‘Culpability and Mistake of Law,’Action and Vulue in Criminal Law eds John Gardner, Jeremy Horder and Stephen Shute (Oxford: Clarendon Press, 1993) pp 157–174.
6. I call the alleged requirement to know the law a ‘duty,’ and the requirement to obey a justified law an ‘obligation.’ I adopt this usage only to avoid confusion, and not because I apply a theory to differentiate duties from obligations.
7. More precisely, an excuse is used to show that a person should not be blamed for performing an act, whether or not that act is wrong. See Douglas Husak ‘The Serial View of Criminal Law Defenses’ (1992) 3 Criminal Law Forum pp 369–400, 400.
8. It does not follow that Smith and Jones should be punished to the same extent, even if they are both liable for having committed the same offence without justification or excuse. Perhaps Smith's ignorance of law functions as a mitigating factor to reduce his sentence relative to Jones's. Of course, anyone who thinks that ignorance of law should be a mitigating factor in sentencing, but not an excuse from liability, must account for why it serves to lessen punishment, but not to preclude it. No adequate theory has yet been produced to explain why some factors should mitigate punishment, while others should preclude it. See Martin Wasik, ‘Excuses at the Sentencing Stage,’ [1983] Criminal Law Review, 450–465.
9. It is barely possible to imagine that a person could be knowingly ignorant of law. Perhaps there is a phenomenon of ‘wilful ignorance’ of law, as there is a phenomenon of wilful ignorance of fact. If so, a person can know that he is ignorant of the law he is violating. However, distinguishing wilful ignorance from recklessness is problematic. See Ira Robbins: ‘The Ostrich Instruction: Deliberate Ignorance as a Criminal Mens Rea,’ (1990) 81 Journal of Criminal Law & Criminology 191–234.
10. For an account of strict liability that emphasizes its connections to the problem of ignorance of law, see Douglas Husak, Philosophy of Criminal Law (Totowa, NJ, Rowman & Littlefield, 1987) pp 136–141.
11. Model Penal Code, American Law Institute Sect 2.04(3). 14. Op Cit, n 4, especially ch 3.
12. Op Cit, n 4, especially ch 3.