Legal moralism is the position that the law can legitimately prohibit conduct simply because a society considers that conduct immoral, even when no one else is harmed by it. It stands opposed to the view that criminal law should only intervene when a person’s actions injure someone other than themselves. The debate between those two positions has shaped obscenity statutes, drug laws, Sunday closing rules, and the now-overturned laws criminalizing private consensual sex.
The Core Claim
The argument behind legal moralism is straightforward: a society’s shared moral beliefs are part of what holds it together, so the state has a legitimate interest in protecting those beliefs through criminal law. The protection extends past preventing violence or fraud. Under legal moralism, the government may criminalize behavior the community considers wrong in itself, regardless of whether anyone is directly injured.
The most influential modern statement of this position came from Lord Patrick Devlin, a British judge, in his 1959 lecture “The Enforcement of Morals.” Devlin argued that society is held together not just by laws and institutions but by “invisible bonds of common thought,” and that shared morality forms part of that binding force. In his view, letting people openly flout conventional morality risked the disintegration of society itself. He wrote that “societies disintegrate from within more frequently than they are broken up by external pressures” and that “the loosening of moral bonds is often the first stage of disintegration.”1Cankaya University. The Enforcement of Morals (1959) by Lord Patrick Devlin
From that premise, Devlin concluded that if society has a right to protect its own existence, it may use the criminal law to preserve morality “in the same way as it uses it to safeguard anything else that is essential to its existence.”1Cankaya University. The Enforcement of Morals (1959) by Lord Patrick Devlin Marriage, he argued, was a clear example: it functions as both a social institution and a moral code, and allowing individual judgments about the morality of adultery would “gravely threaten” it. For Devlin, moral consensus was structural, not optional.
How Legal Moralism Differs From the Harm Principle
The main alternative to legal moralism is John Stuart Mill’s harm principle, laid out in his 1859 essay On Liberty. Mill wrote that “the only purpose for which power can be rightfully exercised over any member of a civilised community, against his will, is to prevent harm to others. His own good, either physical or moral, is not a sufficient warrant.”2Project Gutenberg. On Liberty by John Stuart Mill
Mill allowed that people might have good reason to argue with, persuade, or plead with someone to change their behavior. Those reasons did not justify forcing compliance through law. The only conduct society could legitimately regulate was conduct “calculated to produce evil to some one else.” In the part of life that concerns only the individual, Mill wrote, “his independence is, of right, absolute. Over himself, over his own body and mind, the individual is sovereign.”2Project Gutenberg. On Liberty by John Stuart Mill
The harm principle draws a sharp line between actions that injure others and actions that merely offend or disturb the majority. Under this framework, the fact that most people in a community find gambling or drug use immoral is not, by itself, grounds for making it illegal. There has to be identifiable harm to someone other than the person choosing the behavior. The harm principle remains the dominant framework in liberal legal philosophy.
Joel Feinberg later proposed a middle position in his multi-volume work The Moral Limits of the Criminal Law. His “offense principle” allowed that preventing shock, disgust, or revulsion could sometimes justify legal restrictions even without tangible harm. Public indecency is the classic case: no one is physically injured, but the offense to unwilling observers is real. Feinberg’s approach tried to account for that middle ground without collapsing into full moralism.
How Legal Moralism Differs From Paternalism
Legal moralism is often confused with legal paternalism, and the difference matters. Paternalism restricts your freedom for your own good. Seatbelt laws, motorcycle helmet requirements, and some drug prohibitions have a paternalistic dimension: the government is telling you what to do because it believes you would be better off complying. The justification points inward.
Legal moralism points outward. It restricts your freedom because your behavior offends society’s moral standards, regardless of whether it harms you or anyone else. When a jurisdiction criminalizes prostitution between consenting adults, the moralist justification is not that the people involved will hurt themselves, but that the activity itself is considered wrong.
In practice, the two often overlap. Drug laws, for instance, can be paternalistic (protecting users from addiction), moralistic (punishing conduct considered sinful), or harm-based (preventing impaired driving). Legislators rarely label their reasoning, and a single statute often draws on all three justifications. The distinction still matters, because each justification implies different limits on government power and invites different criticisms.
Examples of Laws Shaped by Legal Moralism
Legal moralism’s fingerprints appear on a wide range of laws, some still enforced and others recently overturned. What unites them is a justification rooted primarily in moral disapproval rather than demonstrable harm to third parties.
Obscenity Laws
Obscenity laws are among the clearest examples of moralism-driven regulation. The First Amendment protects most speech, but the Supreme Court has consistently held that “obscene” material falls outside that protection. In Miller v. California (1973), the Court established a three-part test that remains the standard: material is legally obscene only if the average person, applying contemporary community standards, would find that it appeals to a sexual interest; it depicts sexual conduct in a patently offensive way as defined by state law; and, taken as a whole, it lacks serious literary, artistic, political, or scientific value.3Justia Law. Miller v. California, 413 US 15 (1973)
The “contemporary community standards” language is the moralism built into the legal test. Whether something counts as obscene depends partly on what the local community considers acceptable, a direct appeal to collective moral judgment. A work that passes muster in one community can be prosecuted in another because the moral baseline differs.
Prostitution Laws
Laws criminalizing prostitution often rest on moral condemnation rather than a straightforward harm analysis. The argument is not primarily that sex work injures specific third parties but that it degrades public morality. Some countries have adopted the Nordic model, which criminalizes the buying of sex but not the selling of it. Others have pursued full decriminalization, treating sex work as a labor issue. The ongoing disagreement reflects an unresolved tension between moralism, harm prevention, and individual autonomy.
Drug Criminalization
Many drug laws carry a moralistic dimension beyond harm prevention. Criminalizing personal drug use, particularly when penalties are severe, often reflects a judgment that drug use is sinful or degrading rather than a calibrated response to measurable harm. The fact that alcohol and tobacco, which cause substantial public health damage, have historically been treated more leniently than marijuana illustrates the point. Relative severity of punishment doesn’t always track with relative danger; it often tracks with moral attitudes.
Sodomy and Consensual Sex Laws
For much of American history, laws criminalizing sodomy and other forms of private consensual sexual conduct were explicitly moralistic. These statutes were written to protect “public morals and decency” and grouped alongside laws against adultery, bigamy, and public indecency. Reform efforts frequently met resistance from groups arguing that decriminalization would “promote homosexuality and unnatural conduct.”4Journal of Ethics | American Medical Association. The Decriminalization of Sodomy in the United States
Blue Laws
Sunday closing laws, known as “blue laws,” originated from explicitly religious and moral motivations. Colonial-era statutes prohibited most labor and commerce on the Sabbath. Most provisions governing everyday activities disappeared after the colonial period, but alcohol restrictions persisted into the 21st century. As of 2022, 28 states still maintained some form of Sunday alcohol sales restriction, though the trend has been toward relaxing or repealing them.
Constitutional Limits on Moral Enforcement
The U.S. Constitution places real limits on how far the government can go in enforcing moral views through criminal law. The clearest statement came in Lawrence v. Texas (2003), where the Supreme Court struck down a Texas statute criminalizing sexual conduct between people of the same sex. Justice Kennedy’s majority opinion held that the Texas law “furthers no legitimate state interest which can justify its intrusion into the individual’s personal and private life.”5Justia Law. Lawrence v. Texas, 539 US 558 (2003)
The reasoning cut at the foundations of legal moralism. The Court held that “the fact a State’s governing majority has traditionally viewed a particular practice as immoral is not a sufficient reason for upholding a law prohibiting the practice.” It quoted an earlier case for the principle that “our obligation is to define the liberty of all, not to mandate our own moral code.”5Justia Law. Lawrence v. Texas, 539 US 558 (2003) That is the Court telling legislatures, plainly, that moral disapproval alone does not satisfy constitutional requirements for criminalizing conduct.
In Obergefell v. Hodges (2015), the Court struck down state bans on same-sex marriage, noting that “a long history of disapproval” of same-sex relationships did not justify denying fundamental rights. The Court recognized that laws burdening the liberty of same-sex couples and denying them equal benefits “served to disrespect and subordinate gays and lesbians.”6Legal Information Institute. Obergefell v. Hodges, 576 US 644 (2015) Together, these decisions represent the constitutional system’s clearest rejection of the idea that moral consensus alone can justify restricting liberty.
The Hart-Devlin Debate
The reason legal moralism remains a live concept in philosophy, rather than a settled question, traces back to a specific intellectual exchange. H.L.A. Hart, an Oxford legal philosopher, challenged Devlin in his 1963 book Law, Liberty, and Morality. Hart argued that popular moral disgust was not a sufficient reason to criminalize private behavior. He pressed hardest on Devlin’s central metaphor: the claim that moral consensus is so essential to social cohesion that deviating from it threatens collapse. Hart said this overstated the case. Societies absorb moral disagreement and evolving standards without falling apart. Views on premarital sex, gambling, and alcohol shifted enormously over the 20th century, and societies adapted.
Hart also raised a practical problem: whose morality gets enforced? Devlin appealed to the standards of the “reasonable man,” but Hart pointed out that this assumed a single, identifiable moral consensus. In diverse societies, moral views vary. Elevating one faction’s moral instincts into criminal law meant imposing its values on everyone else. The Hart-Devlin debate remains the starting point for serious discussion of legal moralism because it forced both sides to articulate what had often been left vague: exactly why the state should or should not care about behavior that affects no one beyond the person doing it.
Where Moral Enforcement Stands Today
Legal moralism has not disappeared, but its territory has shrunk. The decriminalization of sodomy, the legalization of same-sex marriage, and the ongoing wave of marijuana legalization reflect a broad shift away from enforcing morality for its own sake. Public opinion on marijuana has flipped: a strong majority of Americans now support legalization, and dozens of states have acted accordingly. What was once framed as a moral failing is increasingly treated as a personal choice or a public health question.
Moralism-based arguments still appear in legislative debates. Proposals to restrict certain kinds of online content, fights over gambling expansion, and arguments about reproductive rights all carry echoes of the same question Devlin and Hart argued over in the 1960s: can the community’s moral convictions justify legal restrictions on individual behavior? One practical lesson stands out from this history. Morality-based laws are less stable than harm-based ones. When the moral consensus shifts, the legal foundation erodes. Sodomy laws that seemed unquestionable in 1960 were unconstitutional by 2003.