in: Oxford Research Encyclopedia of Politics
Modern states pursue most of their (domestic) ends by creating law and acting in accordance with the law they create. Moreover, many believe states ought to pursue most of their ends this way. If a state ought to do something, then chances are it ought to do it by creating, abolishing, changing, upholding, or enforcing some law. Therefore, almost any kind of political philosophy with bearing on what states should do has bearing on what law should be like. Justifying the legal proscription of some conduct involves more than just showing that citizens ought to refrain from that conduct. Legally restricting conduct is an exercise of coercion and must be justified as such. Criminal prohibitions in particular require special justification, as they are not only coercive but also commit the state to deliberately inflict the harm and stigma of punishment on some of its own citizens. Nevertheless, if the state must coerce its citizens, it ought generally to do so through a law that conforms to the rule of law. Law conforms to the rule of law if it is capable of guiding the citizens as they act and plan for the future. This the law can do only if it is open, clear, prospective, and stable, such that citizens can know what it demands now and predict with reasonable certainty what it will demand in the future. Conformity to the rule of law promotes freedom and is required to respect human dignity. Much of the debate about the justification and scope of legal coercion revolves around several principles that advance claims about what considerations are relevant to the justifiability of law. These principles all have the following structure: The fact that a legal restriction of a certain kind is related in a certain way to a certain type of conduct has a certain impact on whether that restriction is justifiable. Common principles include (a) legal moralism, according to which it is always a good reason to criminalize conduct that the conduct is wrongful; (b) the wrongness constraint, according to which criminalizing morally permissible conduct is never justified; (c) liberalism, according to which it is always a good reason to criminalize conduct that the conduct is either harmful or seriously offensive to others, and criminalizing conduct that is neither harmful nor offensive is never justified; (d) the public wrong principle, according to which it is always a good reason to criminalize conduct that the conduct is a public wrong, and criminalizing conduct is never justified unless the conduct is a public wrong; (e) the sovereignty principle, according to which the only legitimate restrictions on conduct are those that secure independence. Which, if any, of these principles one should accept is the subject of an extensive and sophisticated academic debate.