“Much of the criminal law that is regulatory in character — the part of it that deals with malum prohibitum rather than malum in se — is based upon the … principle … that the choice of the individual must give way to the convenience of the many.” Patrick Devlin, The Enforcement of Morals 16 (1968).
“As customarily used these phrases are mutually exclusive. An offense malum prohibitum is not a wrong which is prohibited, but something which is wrong only in the sense that it is against the law. This is emphasized at times by such phrases as ‘malum prohibitum only’ or ‘but malum prohibitum,’ although it is understood without any such qualification. A failure to understand this usage of the terms has led some to assume that all statutory additions to the common law of crimes are mala prohibita. One writer emphasized his confusion by speaking of embezzlement as malum prohibitum. This assumption is utterly without foundation. An act may be malum in se although no punishment is provided by law. If this defect is corrected by appropriate legislation, what previously was malum in se does not cease to be so by reason of having been defined and made punishable by law.” Rollin M. Perkins & Ronald N. Boyce, Criminal Law 884–85 (3d ed. 1982).