What is a crime? A common answer is that crimes are harms. One particular argument is that morality forms the connection between crimes and harms: crimes are not any kind of harm, but specifically a kind of immorality. This position is consistent with natural law jurisprudence which claims that law and morality are inseparably linked. It is also consistent with standard defences of retribution whereby punishment is justified where deserved and to the degree deserved. Retributivist desert is present for individuals that possess some degree of moral responsibility for causing or attempting to cause evil. For example, the murderer deserves severe punishment because he is morally responsible for another person’s death and this act is sufficiently evil to warrant severe punishment.
The idea that crimes are harms to morals — and so their immorality informs their criminality and the corresponding severity of punishment — has also found favour with so-called ‘expressivist’ theories of punishment defended by Joel Feinberg, Antony Duff and others. These theories argue that punishment has an expressivist function of communication public disapproval to criminal offenders for their moral wrongdoings where punishment is proportionate to immorality.
The justification of crimes as harms to morals is part of a venerable tradition that has come to be increasingly seen as discredited. Most academics working in law (and even more practising lawyers) reject natural law jurisprudence and support some version of the separability thesis of legal positivism where law and morality are held to be separable, but not intrinsically and necessarily linked. Yet, curiously, retributivist theories, including expressivism, have been on the ascendency with a growing number of legal philosophers defending the idea of crimes as harms to morals and, therefore, moving in a contrary direction to most others working in law and academic law.