How Illinois Courts Handle Adultery

What Are Illinois’s Adultery Laws?

The last update to Illinois adultery laws was in 1961. By law, adultery is defined as having sexual relations with someone who is not your spouse in an “open and notorious” way^[1].

What behavior explicitly falls under “open and notorious” is up for debate. Regardless, adultery remains a Class A misdemeanor that can land you a fine of up to $2,500 and up to a year in jail.

In reality, even though the law is still around it is rarely enforced. The last time it was used was in 1997 in a case where the prosecutors were baffled to see it actually used^[2].

So why have the laws at all? That’s hard to say. Maybe lawmakers don’t want to publicly take a stance for getting rid of them. Or maybe getting rid of a law that will never get charged is just more trouble than it’s worth.

How Does an Affair Impact My Divorce?

In order for a person to get a divorce in the past, they had to prove their spouse did something wrong. The reasons could be things like desertion, cruelty, or adultery.

In 2016, Illinois made some huge updates to its divorce law. One of the biggest changes was that Illinois officially became a No-Fault divorce state. This means that you no longer have to prove any sort of wrongdoing to get a divorce. Currently, the only reason accepted for divorce in Illinois is irreconcilable differences.

Many people expect a cheating spouse to be “punished” as part of a divorce. They think that proof of infidelity is enough to sway a judge when deciding child custody or alimony. However, this is not the case. Adultery can’t be used as legal grounds to make decisions on property division, child custody, or support.

That isn’t to say an affair would have no impact whatsoever. For instance, what if an unfaithful spouse spent money from marital assets on the affair? This is called “dissipation” of marital funds, and a judge might consider adjusting the property division to account for this.

Also, if an affair can be decisively proven to have a negative effect on your children’s wellbeing, it might affect the outcome. Such proof would need to be tangible and compelling for it to be taken into account.

What Should I Do If I Suspect My Spouse is Having an Affair?

Unfortunately, there is not much you can do beyond trying to get as much tangible proof of it as possible. But you should always be mindful of how you collect it and to make sure it’s legal. In Illinois, it is against the law to record conversations without consent. If you are in doubt about what is an isn’t legal, it is best to consult Illinois’s privacy laws^[3].

If you’re considering using a private investigator, we would instead recommend an experienced family attorney. Private investigators can be extremely expensive, and may not gather the type of proof that would say a judge. Remember, proof of the affair alone would not be enough to affect the outcome of a divorce judgment.

Since family attorneys work regularly in the family law system, they could best advise you on what evidence would help your case.