Adultery remains a crime in roughly a dozen states, though actual criminal prosecutions are extraordinarily rare. Federal law has never classified adultery as a criminal act; this has always been left entirely to individual states, and most states have moved away from criminalizing it entirely over the past several decades.
Which States Still Have These Laws on the Books
Michigan, Oklahoma, and Wisconsin classify adultery as a felony. Michigan’s law carries up to five years in prison, Oklahoma’s carries up to five years alongside a fine, and Wisconsin treats it as a felony carrying up to three and a half years plus a fine reaching $10,000. A broader group of states, including Alabama, Arizona, Florida, Georgia, Illinois, Kansas, Mississippi, and South Carolina, classify adultery as a misdemeanor, typically carrying penalties like short jail sentences or modest fines, sometimes as low as ten dollars in states like Maryland.
The Steady Trend Toward Repeal
The overall direction here has been consistently toward decriminalization. Colorado repealed its adultery law in 2013, New Hampshire in 2014, Massachusetts in 2018, Utah in 2019, Idaho in 2022, and Minnesota in 2023. New York repealed its 1907-era adultery statute in 2024, following a push from lawmakers who argued that criminalizing private, consensual conduct between adults no longer belonged in modern criminal codes. Given this trajectory, it’s reasonable to expect the list of states still criminalizing adultery to keep shrinking rather than growing.
Why Prosecutions Almost Never Actually Happen
Even in states where adultery technically remains a crime, prosecutors overwhelmingly decline to pursue these cases. The reasons are fairly practical. Adultery cases consume public resources to resolve what’s fundamentally a private relationship dispute, juries tend to be genuinely unsympathetic toward criminal charges over infidelity, and proving the case requires an invasive evidence-gathering process that most prosecutors simply don’t consider worth the effort compared to more serious crimes competing for their limited time and attention.
The Constitutional Question Hanging Over These Laws
There’s a meaningful legal cloud over adultery statutes that hasn’t been fully resolved by the Supreme Court. In the 2003 case Lawrence v. Texas, the Court struck down a state sodomy law on the grounds that government cannot criminalize private, consensual sexual conduct between adults. The majority opinion explicitly declined to address adultery directly, but the dissent pointed out the obvious tension, noting that the same reasoning could logically extend to laws against adultery, bigamy, and other private consensual conduct between adults. This unresolved question means adultery statutes exist in a genuinely uncertain constitutional position, even in the states that haven’t formally repealed them.
What Actually Counts as Adultery Under These Laws
State definitions vary more than most people expect. Some states require only a single instance of sexual intercourse to meet the legal definition. Others require proof of habitual conduct, cohabitation, or what’s sometimes called “open adultery,” meaning the couple lived together openly as though married. This distinction matters practically; a state requiring open, habitual conduct sets a much higher bar than one where a single documented instance could theoretically satisfy the statute’s elements.
Where Adultery Genuinely Matters Legally Today
While criminal prosecution is essentially nonexistent, adultery still carries real weight in a different legal arena entirely: divorce and family court. In fault-based divorce states, proof of adultery can influence alimony awards and how property gets divided. No-fault divorce states, including California, generally ignore infidelity entirely when dividing assets or determining custody, focusing instead on equitable division regardless of who did what during the marriage.
The Lesser-Known Civil Lawsuit Option
A small number of states, including North Carolina and South Dakota, still recognize what’s called an “alienation of affection” claim, allowing a wronged spouse to sue the third party who was involved with their partner. A related civil claim called “criminal conversation,” despite its name, is also a civil action rather than a criminal charge, and it simply requires proving that sexual intercourse occurred between the defendant and the plaintiff’s spouse. These lawsuits seek monetary damages rather than criminal penalties, and while genuinely rare, they do occasionally result in real financial judgments in the handful of states that still allow them.
Clearing Up a Viral Misconception
A false claim circulated widely online in 2025 suggesting that a new federal law would make cheating “after signing marriage papers” illegal starting in 2026, with posts claiming violators could be arrested for breaching a contract. This claim has no factual basis whatsoever; no such federal legislation exists or has been proposed, and the reality remains exactly what it’s been for years: adultery is a state-level issue, criminalized in a shrinking handful of states, essentially never prosecuted, and with no indication of any new nationwide criminalization on the horizon.
FAQs
Q1. Can my spouse actually have me arrested for cheating if we live in a state where adultery is illegal?
It’s technically possible in states that still criminalize adultery, but prosecutors almost universally decline to pursue these cases, making actual arrest and conviction extremely unlikely in practice.
Q2. Does adultery affect how much alimony I’ll receive in a divorce?
It depends entirely on your state. Fault-based divorce states may factor infidelity into alimony and property decisions, while no-fault states like California generally disregard it entirely.
Q3. Can I sue the person my spouse had an affair with?
Only in a small number of states that still recognize alienation of affection or criminal conversation claims, such as North Carolina and South Dakota. Most states have eliminated these types of lawsuits entirely.
Q4. Is sexting considered adultery under these criminal laws?
No, most state adultery statutes specifically require actual sexual intercourse to meet the legal definition, though sexting could potentially serve as supporting evidence in a broader adultery case or divorce proceeding.
