The role of the state, in spheres ranging from public morality to the economy, is one of several axes around which debates about the conservative movement’s future are presently revolving.

In a 2020 article, I mon-good constitutionalism for its misreading of how the natural law tradition treats the role of the state and law vis-à-vis morality. Far from giving legislators, judges, and governments a free hand to aggressively shape the moral culture, I maintained that the natural law’s conception of mon good – specifically, the mon good – actually puts in place principled and significant limits on what state officials may do in this area.

That, however, does not mean that natural law indicates that the law may do nothing in the realm of virtue. Contra those who insist that “you can’t legislate morality,” it is in fact impossible for law and legislation to refrain from shaping the moral culture.

One reason for this is that all laws have a moral logic built into them. Even something as mundane as traffic laws are underpinned by moral reasoning. Why? Because the most basic reason that we decide that everyone must drive on the right-hand side of the road rather than the left – or down the middle, or whatever side takes one’s fancy – is that human life is a good to be protected. Absent a formal decision to identify one side of the road than another, many people will likely be hurt and killed. Ergo, we legally regulate the free choices of millions of people to drive vehicles every day.

It’s also the case that some of the most basic legal foundations of free and just societies depend on acceptance of a conception of morality that takes reason seriously. Take, for instance, rule of law.

In his much-read book The Morality of Law (1964), the legal philosopher Lon L. Fuller famously maintained against the legal positivists of his time that rule of law incarnates an inner moral logic, inasmuch as there are certain conditions of reason that a law must meet before it is understood to be legitimate. For Fuller, rule of law meant that a law must be:

sufficiently general;publicly promulgated (e.g., you cannot have secret laws);prospective (i.e., applicable only to future, and not past, behavior);clear and intelligible;free of contradiction;relatively constant, in the sense insofar as they are sufficiently stable to allow people to be guided by their knowledge of the content of the rules;possible to obey; andadministered in a way that does not wildly diverge from their obvious or apparent meaning.

Unless, for instance, a law is clear and promulgated, it is unreasonable and, therefore, unjust. Note, however, that this requirement is not simply a technical precondition for a functioning legal system. It contains an inner reasonableness, insofar as these requirements testify that there are just (reasonable) and unjust (unreasonable) ways of applying laws and treating people. When a law fails to meet these criteria, we can say that rule of law degenerates into “rule of men.” In other words, rule of law minus principles of reason guarantees a failure to achieve justice and the triumph of arbitary government.

Another way in which law influences a society’s moral culture is through its pedagogical function. We don’t simply have laws against stealing or murder, because it’s an inconvenience to us and others to have our property arbitrarily taken from us or for our lives to be intentionally terminated by someone. These same laws and the punishments applied to those who break them also send a message to everyone living in a given society.

And the message is this: It is morally wrong and unjust to steal from or kill other people. The more people understand and internalize this message, the more likely it is that they will refrain such acts and learn to respect other people’s lives and property.

Law’s pedagogical role has been recognized and explicated upon by natural law thinkers from Aristotle onwards. Aquinas, for instance, states that “the purpose of law is to lead men to virtue, not suddenly, but gradually.” To this extent, we can say that law has not just the function of coordinating the billions of free choices made by munities, and governments every day. Law also has a civilizing dimension, and civilization includes but also goes beyond rights and freedoms.

Before, however, people get carried away and imagine that this means that natural law gives license to judges and legislators to engage in whatever moral prodding they want, whenever they want, three factors should be noted.

First, Aquinas attached all sorts of prudential considerations to his basic point about law’s contribution to inculcating virtue in a given society. One of these, he says, is the need to fit law to the condition of the people and to adapt it “to place and time.” Much depends on the condition of the society over which rulers preside. Aquinas referred, for example, to Augustine’s famous observation about the need sometimes to tolerate (as distinct from approve) vices like prostitution, “so that men do not break out in worse lusts.”

Second, natural law underscores that other authorities have the primary responsibility for shaping the moral culture of munities. Parents have the prime obligation to raise their children in the virtues – not magistrates or senators.

Third, as I wrote in my original critique mon-good constitutionalism, the mon good that is the state’s concern (the mon good) “limits what the public authorities may do vis-à-vis the promotion of virtue,” because the object of many acts of virtue is the private good of individuals, families and munities. Such acts fall outside the immediate scope of the mon good for which the state is responsible.

Natural law’s position vis-à-vis the role of law and a society’s moral culture, thus, does not lend itself to the support of those who regard law as the main tool to be deployed for leading society in the direction of the virtues. Nor, however, does natural law support those who believe that law has no role in this area, save to promote rights and liberty. In short, natural law’s understanding of the law’s relationship to morality is clear but nuanced. Wider understanding of some of those nuances, I’d suggest, would make for a more productive discussion of this topic in conservative circles today.