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Wisconsin Watch partners with Gigafact to produce fact briefs — bite-sized fact checks of trending claims. Read our methodology to learn how we check claims.


Wisconsin’s adultery law prohibits married individuals from having sexual intercourse with anyone who is not their spouse. It was enacted in 1849.

The law states that anyone who commits adultery is guilty of a Class I felony, which carries a maximum $10,000 fine and 3.5 years in prison.

Several states continue to have such fornication and adultery laws criminalizing extramarital sex on the books. But it has been decades since anyone was prosecuted under such laws, including in Wisconsin.

Some states have made efforts to remove or amend these laws in recent years. But some lawmakers have resisted such initiatives, fearing pushback from constituents who believe eliminating bans on extramarital sex could lead to moral decay.


Wisconsin State Legislature: Wisconsin statutes: 944.16 adultery

Google Books: A Guide to America’s Sex Laws: Page 110

Salon: Adultery and fornication: Why are states rushing to get these outdated laws off the books?

New York Times: Adultery as a crime: Old laws dusted off in a Wisconsin case

Wisconsin State Legislature: Wisconsin Legislature: 939.50

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Jacob Alabab-Moser / Wisconsin WatchFact Checker

Jacob Alabab-Moser joined as Wisconsin Watch’s fact checker in September 2022, as part of the effort by The Gigafact Project in partnership with different state-level news outlets to combat misinformation in the 2022 midterm elections. Jacob has several years of experience as a fact checker and research assistant at a variety of organizations, including at The Gigafact Project. He holds a BA from Brown University and is pursuing a MSc from the London School of Economics and Political Science.