Adultery

Adultery is sexual infidelity by a married person. Conservatives treat it as a breach of a public promise rather than a private lapse, because marriage in the conservative account is a contract whose beneficiaries include children, in-laws, and the wider community that relies on stable households.

The disagreement with modern liberal opinion is not about whether adultery causes pain. It is about whether the harm is confined to the couple. Conservatives argue that it is not, and that a society which treats marital promises as revocable at will pays for it in family breakdown, child poverty, and litigation.

Key Takeaways

• Conservatives locate the wrong of adultery in the broken vow, not in the sexual act as such, which is why deceit aggravates it.
• Every major legal tradition — Mosaic, Roman, canon, and English common law — treated adultery as a matter for public authority until the twentieth century.
• Western states decriminalised adultery over roughly a century, ending with the last United States prosecutions falling into disuse; conservatives divide over whether this was correct.
• The conservative case rests on consequences for children and on the reliability of promises, not on a demand for state punishment.
• Critics answer that criminal or fault-based sanctions produced perjury, blackmail, and trapped spouses without measurably reducing infidelity.

History And Context

The prohibition is among the oldest recorded in law. The Code of Hammurabi, dating to roughly 1750 BC, prescribed drowning for an adulterous wife and her partner unless the husband spared them. The seventh commandment in Exodus 20 states the rule flatly, and Leviticus 20:10 attaches the death penalty. Rome codified the offence under Augustus in the lex Julia de adulteriis coercendis of 18 BC, which made adultery a public crime that any citizen could prosecute once the husband or father had let a sixty-day priority period lapse and required a husband to divorce an unfaithful wife or face a charge of pandering.

Medieval Europe moved jurisdiction to the church. From the twelfth century, ecclesiastical courts in England heard adultery cases alongside other matrimonial disputes, imposing penance rather than execution. The Commonwealth Parliament briefly reversed this in the Adultery Act of 1650, which made the offence capital; enforcement collapsed because juries refused to convict, and the statute lapsed at the Restoration in 1660.

The nineteenth century made adultery the pivot of divorce law rather than of criminal law. England’s Matrimonial Causes Act 1857 moved divorce from Parliament to the courts and set adultery as the sole ground, with an asymmetry that let a husband sue on adultery alone while a wife had to prove adultery plus cruelty or desertion. That asymmetry was removed in 1923. Nathaniel Hawthorne’s The Scarlet Letter (1850), set in Puritan Boston, fixed the punishment of the adulteress in the Anglophone imagination at the moment the practice was ending.

The twentieth century dismantled the legal apparatus. England abolished the action for criminal conversation in 1857 and damages against a co-respondent in 1970. The Divorce Reform Act 1969 introduced irretrievable breakdown, and the Divorce, Dissolution and Separation Act 2020 removed fault entirely from English divorce from April 2022. In the United States, adultery statutes remain on the books in about fifteen states but are almost never charged, and Lawrence v. Texas (2003) cast doubt on their constitutionality.¹

The Conservative Position

Conservatives begin with the nature of a vow. Marriage is not a description of present feeling but a promise about future conduct, and its social value comes from being harder to exit than an ordinary contract. Roger Scruton argued that erotic love acquires its meaning through commitment, and that treating sexual acts as private transactions between consenting adults empties them of the significance participants themselves want them to have.²

The second argument is about children. Conservatives point to the association between family dissolution and outcomes for children in education, income, and involvement with the criminal justice system. Charles Murray’s Coming Apart (2012) documented the divergence in marriage rates between American professional and working-class communities after 1960 and argued that the collapse of marital norms fell hardest on those with the fewest resources to absorb it.³ Adultery is among the causes most commonly cited when marriages end.

The third argument concerns institutions rather than statutes. Most conservatives do not want adultery prosecuted. Edmund Burke’s account of society as a partnership across generations implies that the load-bearing work is done by custom, religion, and reputation, not by police.⁴ What conservatives object to is the further step of declaring infidelity morally neutral — a matter of personal authenticity — because a promise that carries no stigma when broken has ceased to be a promise.

Differing Positions

Liberal critics argue that the historical record refutes the conservative case on its own terms. Fault-based divorce produced staged evidence, collusive hotel bookings, and perjury on an industrial scale in England between 1857 and 1969. Criminal statutes were enforced selectively and against women. On this reading, moralised law delivered hypocrisy rather than fidelity.

A second objection concerns the direction of causation. Sociologists who study divorce argue that adultery is more commonly the symptom of a marriage already failing than its cause, and that the outcomes for children attributed to divorce reflect prior conflict, poverty, and parental characteristics. Removing the exit does not restore the marriage; it produces households where children witness sustained hostility.

A third position, argued from within liberalism, holds that sexual conduct between adults falls outside the state’s competence altogether, and that non-monogamous arrangements entered into honestly involve no broken promise. On this view the wrong in adultery is deception, and deception is already condemned without any appeal to the institution of marriage.

References

1. Lawrence v. Texas, 539 U.S. 558 (2003).
2. Roger Scruton, Sexual Desire: A Philosophical Investigation (Weidenfeld & Nicolson, 1986).
3. Charles Murray, Coming Apart: The State of White America, 1960–2010 (Crown Forum, 2012).
4. Edmund Burke, Reflections on the Revolution in France (J. Dodsley, 1790).