Most people have no idea adultery is actually illegal in Wisconsin. Seriously. But here’s the thing: it’s been on the books since 1849, and technically, you could face felony charges. Let’s break down what this really means for you in 2026.
The law exists, but the reality is totally different. Stay with me here.
What Is Adultery Under Wisconsin Law?
Wisconsin defines adultery pretty clearly. It’s when a married person has sexual intercourse with someone who isn’t their spouse. That’s it.
But here’s where it gets interesting. The law also applies to the unmarried person. If you knowingly have sex with someone who’s married to another person, you’re breaking the law too. Both parties can be charged.
This comes from Wisconsin Statute 944.16, written way back in 1849.
Is Adultery Really a Crime?
Okay, pause. Read this carefully.
Yes, adultery is classified as a Class I felony in Wisconsin. A Class I felony can mean up to 3.5 years in prison. You could also face fines up to $10,000.
Sounds serious, right?
Here’s the reality check. Criminal charges for adultery are rarely pursued in Wisconsin courtrooms. The last prosecution anyone knows about happened in 1990. That was over 35 years ago.
Pretty much never enforced, honestly.
Why does this law still exist if nobody uses it? Good question. Some lawmakers keep it around to show a commitment to traditional values. Others argue it conflicts with modern privacy rights.
The No-Fault Divorce Contradiction
Wisconsin has been a no-fault divorce state since 1977. What does that mean for you?
It means you can get divorced without proving anyone did anything wrong. You just have to say the marriage is broken beyond repair. That’s literally all you need.
So here’s the weird part. The state has a law making adultery a felony. But the same state doesn’t require you to prove adultery to get divorced. They contradict each other.
Wisconsin law even states that although the state does not regulate private sexual activity between consenting adults, it does not condone any form of sexual conduct outside marriage.
Confusing? Totally.
Can You Be Charged While Separated?
Wondering if this applies during separation?
Technically, yes. A legal separation doesn’t end your marriage. You’re still married. Any sexual intercourse with someone other than your spouse fits the legal definition of adultery.
But remember what we said earlier. The law exists, but prosecutions don’t happen. District attorneys simply don’t pursue these cases anymore.
Not since 1990, actually.
What About Divorce Proceedings?
Hold on, this part is important.
Even though adultery won’t land you in criminal court, it can still affect your divorce. Just not in the ways you might think.
Courts cannot consider adulterous acts when making decisions in a divorce. This means judges won’t give your spouse more money or better terms just because you cheated.
But there are exceptions. Let’s break them down.
When Adultery Matters Financially
Infidelity is most commonly relevant financially if it resulted in the use of marital assets for non-marital purposes.
Here’s what that means in plain English. Did you use joint money to pay for hotels? Buy gifts for your affair partner? Take expensive trips together? That’s called marital waste.
The court can make you reimburse your spouse for those expenses. There’s a one-year lookback period before the divorce filing where it’s easier to prove waste. Going back further is harder but not impossible.
You could owe your spouse back for money you spent on the affair.
Child Custody Concerns
This is where things can get tricky.
If the cheating spouse wants their new partner involved with the children and the other parent objects, the cheating partner will become relevant.
The court will ask questions. Who is this new person? Can they be trusted with your kids? Will their presence harm the children emotionally or physically?
If your new relationship creates concerns about your children’s wellbeing, expect the affair to come up in custody discussions.
Penalties for Adultery (If Prosecuted)
Let’s talk about what could theoretically happen.
As a Class I felony, adultery carries specific penalties under Wisconsin law. You’re looking at a maximum fine of $10,000. Prison time could reach 3.5 years.
Think of it like a serious theft charge. Similar level of felony, similar potential consequences.
But again, this almost never happens. The criminal justice system has bigger priorities. Murders, assaults, robberies. Those get attention. Extramarital affairs? Not so much.
Honestly, your bigger worry is how it affects your divorce settlement.
Can You Sue for Adultery?
Short answer: No.
Wisconsin used to have something called alienation of affection laws. These let you sue the person who broke up your marriage. You could go after the affair partner directly.
That statute has been abolished, meaning there is no longer a basis for filing a lawsuit for alienation of affection.
You cannot sue your spouse’s lover. You cannot sue your spouse for damages because they cheated. Those legal options don’t exist anymore.
Alimony and Property Division
Does cheating mean you’ll pay more alimony? Nope.
Alimony, called maintenance in Wisconsin, is not affected by adultery. The court looks at other factors. How long were you married? What’s each person’s earning capacity? Can one spouse support themselves?
Infidelity doesn’t enter the equation.
Same goes for property division. Courts cannot consider adultery when dividing marital property in Wisconsin. Having an affair doesn’t mean you get less. Being the victim of an affair doesn’t mean you get more.
The split happens based on what’s fair, not who cheated.
Dating Before Divorce Is Final
Sound complicated? It’s actually not.
In Wisconsin, adultery remains a Class I felony under state law, but it’s almost never enforced. If you start dating before your divorce is finalized, are you technically breaking the law? Yes.
Will the police arrest you? Will your spouse successfully press charges? Almost certainly not.
But here’s some free advice. Wait until the divorce is done. Not for legal reasons. For practical ones. New relationships during divorce proceedings create drama. They complicate negotiations. They make things messier.
Save yourself the headache.
What to Do If Accused
Let’s say your spouse is threatening to report you for adultery. What should you do?
First, don’t panic. Remember the last prosecution was in 1990. The district attorney’s office isn’t going to suddenly decide your case is the one they’ll pursue after 36 years.
Second, document everything related to marital waste. If you’re being accused of spending joint funds on an affair, gather bank statements, credit card records, receipts. Show where the money actually went.
Third, talk to a family law attorney. Not because you need criminal defense. Because you need someone who understands how adultery can affect property division and custody in your specific situation.
Most importantly, focus on the divorce itself. That’s where the real consequences happen.
The 1990 Case
You’re probably wondering about that last prosecution. What actually happened?
In 1990, Wisconsin found its way in the national spotlight when a 28-year-old woman was charged during a divorce. The charges were eventually dropped after she completed 40 hours of community service and parental counseling.
That’s it. One case in over three decades. The woman wasn’t convicted. She just did community service and the whole thing went away.
This shows you how rare enforcement really is.
Modern Legal Perspective
Here’s the thing most people miss.
Wisconsin is caught between old morality laws and modern privacy rights. The adultery statute is literally from the 1800s. It was written when people had to prove fault to get divorced.
Times have changed. The law hasn’t been updated.
Wisconsin judges are unlikely to allow criminal complaints on cheating, generally considering it a moral and private issue outside the jurisdiction of courts.
The legal system has moved on, even if the statute book hasn’t.
Mediation and Alternative Dispute Resolution
Honestly, this is the part most people should pay attention to.
If adultery is part of your divorce story, consider mediation. Mediation is a voluntary process overseen by an impartial third party, typically an attorney with experience in family law.
You can work through property division, custody arrangements, and support payments without going to court. The mediator helps you reach agreements. Everything stays more private. Less stressful than traditional court proceedings.
All agreements need court approval before they’re legally binding. But you avoid lengthy trials and their associated drama.
Arbitration is another option. Both spouses agree on an arbitrator who makes binding decisions on contested issues.
These alternatives often work better when emotions are running high.
Protecting Yourself
Not sure what counts as a violation?
The best protection is understanding your rights and obligations. If you’re going through a divorce where adultery is an issue, keep these things in mind.
Track all spending. If you’re using marital funds, document everything. This protects you from waste allegations later.
Think carefully about introducing new partners to your kids. The court’s main concern is the children’s wellbeing. If your new relationship could raise red flags, wait.
Get legal advice early. Family law attorneys have seen it all. They can tell you what matters in your specific county with your specific judge.
Keep things civil with your spouse if possible. Angry spouses make threats about criminal charges. Calm spouses negotiate settlements.
Statistics and Current Trends
Pretty straightforward.
Adultery laws exist in several states beyond Wisconsin. But prosecutions are incredibly rare everywhere. Most states have moved to no-fault divorce systems.
Some states have tried removing these old laws from the books. Others keep them despite never using them. It’s basically a political question at this point.
In Wisconsin specifically, family law attorneys report they’ve never seen an adultery prosecution in their entire careers. Many have practiced for 20, 30, even 40 years.
The trend is clear. These laws are relics.
What You Need to Know Right Now
Let’s wrap this up with the essentials.
Adultery is technically illegal in Wisconsin. It’s a Class I felony that could mean prison time and heavy fines. But nobody gets charged with it. The last known case was in 1990.
For divorce purposes, adultery usually doesn’t matter unless you wasted marital assets or created problems for your kids. Courts don’t consider it when dividing property or awarding alimony.
You can’t sue someone for breaking up your marriage. Those alienation of affection laws are gone.
If you’re dealing with a divorce involving infidelity, focus on the family law issues. That’s where real consequences happen. Criminal prosecution isn’t a realistic concern.
Most importantly, get professional legal help. Every divorce is different. What matters in your case depends on your specific facts, your county, and your circumstances.
Frequently Asked Questions
Is adultery really illegal in Wisconsin in 2026?
Yes, it’s still technically illegal as a Class I felony. However, the law hasn’t been enforced since 1990 and prosecutions are extremely unlikely.
Can I go to jail for cheating on my spouse?
Theoretically yes, but practically no. The maximum penalty is 3.5 years in prison, but district attorneys don’t pursue these cases anymore.
Will adultery affect my divorce settlement?
Not directly. Wisconsin is a no-fault divorce state, so courts don’t consider who cheated when dividing property or awarding alimony. But if you spent marital money on the affair, you might have to reimburse your spouse.
Can my spouse’s boyfriend or girlfriend be charged with adultery?
Legally yes, the law applies to both the married person and their affair partner. In reality, neither person will be prosecuted.
What if I’m legally separated but not divorced?
You’re still married during legal separation, so technically the adultery law still applies. But again, enforcement doesn’t happen.
Can I sue the person my spouse had an affair with?
No. Wisconsin abolished alienation of affection lawsuits. You cannot sue the affair partner or your spouse for damages related to infidelity.
Does adultery impact child custody decisions?
It can, but only if the affair or new relationship negatively affects the children’s wellbeing. Courts care about whether your new partner is safe and appropriate around your kids.
Should I wait until my divorce is final before dating?
While you won’t face criminal charges, it’s often smarter to wait. New relationships during divorce complicate negotiations and can create unnecessary conflict.
Final Thoughts
Now you know the basics. Wisconsin’s adultery law exists on paper but not in practice. It’s an old statute from a different era that nobody enforces anymore.
For practical purposes, worry about how infidelity affects your divorce, not whether you’ll face criminal charges. Focus on protecting your assets, your kids, and your future.
If you’re going through a divorce involving adultery, talk to a family law attorney. They can guide you through what actually matters in Wisconsin courts today.
Stay informed, stay calm, and remember that laws on the books don’t always match reality.
References
- Wisconsin Statute 944.16 – Adultery (https://docs.legis.wisconsin.gov/document/statutes/944.16)
- Wisconsin Statute 939.50 – Classification of Felonies (https://docs.legis.wisconsin.gov/document/statutes/939.51)
- Sterling Lawyers – How Wisconsin Courts Deal with Adultery (https://www.sterlinglawyers.com/wisconsin/divorce/adultery-laws/)
- Wisconsin Watch – Is adultery against the law in Wisconsin? (https://wisconsinwatch.org/2022/12/is-adultery-against-the-law-in-wisconsin/)
- Karp & Iancu – Wisconsin Divorce Laws for Adultery (https://www.karplawfirm.com/resource/can-you-sue-for-adultery-in-wisconsin/)
- Divergent Family Law – How Adultery Impacts Divorce in Wisconsin (https://www.divergentfamilylaw.com/wilawyers/wisconsindivorcelaws/adultery-laws/)
