Divorce breeds distrust. In today’s technology-driven society, distrust can lead to cyber-spying. No doubt, when you are going through your divorce, there is often a compulsion to see what your spouse is up to. Some want to know if there is cheating and others just want financial information. And some arrive at this question from the other side, with the uneasy feeling that they are the ones being watched. Every one of those situations runs through the same set of Illinois laws. Some of those laws carry criminal penalties.
Some spying between spouses is legal in Illinois, and some of it is a crime. Three questions can decide which:
- Did the other person consent?
- Who owns the device, the account, or the vehicle?
- Was the information captured openly, or in secret?
Information your spouse hands you, a text, an email, a public post, is generally fair to use. Information taken secretly is different. A hidden recorder, a tracker on their car, or spyware on their phone can bring criminal charges. What it captures usually cannot be used in court either. This guide walks through the common scenarios, with real cases from our Chicago family law practice.
Key Takeaways
- Recording your spouse without their consent could be a crime in Illinois, and the recording usually cannot be used in court.
- Putting a tracker on a car that is not registered to you could bring criminal charges, even against a spouse.
- Anything your spouse sends you directly, texts, emails, voicemails, could potentially be used as evidence.
- Shared devices and shared accounts are the gray zone; what you both set up is hard to call spying.
- If you think you are being watched, do not confront your spouse; preserve what you find and tell your attorney.
How Spying Has Changed, and How the Law Followed
Just after I left the prosecutor’s office, I took a job with Pinkerton, the detective agency. I was charged with selling Pinkerton’s services to lawyers, and to sell the service I had to learn it. And so I became a Pinkerton detective, if only for a short time. I got to protect the Wienermobile from the PETA folks. I got to dumpster dive and send a 50-pound flowerpot to a man on worker’s compensation who claimed a bad back. I got to sit in the van and watch the professionals take pictures of that same man lifting that flowerpot onto his porch. Stuff like that. It was fun and exciting and I almost thought detective work would be better than the law.
All of that was lawful, and it took patience. Surveillance meant a camera, a parked van, and a public street. Back before we had cell phones and computers, spying on someone was done the old-fashioned way, by following them around. Following people around was rarely illegal, and what it produced, we were able to use in court.
Then the equipment left the van. Consumer GPS units made tracking cheap, and phone software made it invisible. Today the tools are ordinary consumer technology, and most of it is already in the house:
- Location tags such as AirTags, slipped into a bag or a bumper
- Connected-car apps that report where the car is parked
- Shared phone plans and shared Apple or Google accounts that sync messages and locations on their own
- Spyware sold as monitoring software
- Social media, where people hand over the rest voluntarily
- Smart speakers and cameras; what smart home devices record has become its own category of family law evidence
Illinois law has moved in the same direction, and it has moved toward restriction. Secret recording was a crime here long before the phone in your pocket could do it quietly. Vehicle tracking is now its own offense. The pattern is worth carrying into every decision below. As the tools got easier, the law got stricter, and the distance between what is easy and what is legal is where people get into trouble.
Listening Devices on the Children
More and more, I see parents installing a listening device on their children to spy on the other parent. Initially, of course, the devices were supposed to be spying on the children and not the spouse, but it is too easy and too tempting. We now see them in the child’s teddy bear or on their backpack. These types of devices listen in on everything that is going on in the other parent’s home. And it is illegal. The recording is likely barred from court, and the parent who planted it could face criminal charges.
How Illinois Law Treats Spying During a Divorce
Whether something crosses the line into a crime depends on the details, and that is a question for a criminal defense attorney. We practice family law. In a divorce or custody case, a judge will look at whether the evidence can come in at all, and whether the way you gathered it counts against you.
Illinois is an all-party consent state. Under the eavesdropping law (720 ILCS 5/14-2), recording a private conversation is generally a crime unless everyone in it consents. That covers hidden recorders, secret phone recordings, and the listening devices above. It does not matter that the person recorded is your spouse.
Reading a spouse’s private email or logging into their accounts without permission is classic electronic snooping during a divorce. Doing that opens you to potential civil claims and criminal charges of your own.
The court rules add a second layer under Illinois Supreme Court Rule 219. Information obtained improperly, through abuse of the discovery procedures, can be suppressed. The judge can also sanction the party who gathered it, including ordering them to pay the other side’s fees. Illegally gathered material thus tends to hurt the person who gathered it, twice over.
Spyware apps marketed as monitoring software deserve their own warning. Installing one on a phone can violate two laws at once: eavesdropping and Illinois computer tampering.
Can I Put a Tracker on My Spouse’s Car?
In most cases, no. Illinois law makes vehicle tracking a crime under 720 ILCS 5/21-2.5. Placing an electronic tracking device without the consent of the vehicle’s registered owner, lessor or lessee, is a Class A misdemeanor. The consent that matters is the registered owner’s, lessor’s or lessee’s. Marriage is not an exception, and neither is having paid for the car. If the car is registered to your spouse alone, placing a tracker on it could be charged as a crime.
Some tracking still uses a purpose-built GPS box hidden in a wheel well. Most of it happens through an AirTag in a bag, an app on the phone, or the car’s connected services. If you suspect a tracker, the technology works in your favor. iPhones and many Android phones alert you when an unknown AirTag travels with you. A professional sweep still makes sense for dedicated GPS units.
An order of protection case, which can be civil in nature and not criminal, turned into a criminal case. The woman found a tracking device on her car after the order was entered. The tracking crossed into criminal territory. Many types of situations can lead to criminal charges when you spy on another person. If you are going through a divorce, you might want to have your devices checked for spyware.
Can I Read My Spouse’s Texts, Emails, or Accounts?
If it was common in your marriage to use your spouse’s phone, you likely knew the password. If you were given permission once and it was never taken away, going back in is not always considered spying.
This is the grayest zone on the page. Permission can be revoked, accounts get separated, and a judge looks at what was reasonable at the time. When in doubt, stop and ask your attorney before you open anything.
When Devices and Accounts Are Shared
One of my favorite cases involved a couple who shared several devices and used the same Apple password. Have you ever looked at your iPad and found your texts and email showing up on both your iPhone and the iPad?
The husband had forgotten that. When he moved out he took his phone, but his wife kept the iPad. She did not notice at first, and then text messages started arriving on it.
Opening them, she could see, in real time, the texts between her husband and his girlfriend.
She did not care much about the girlfriend; she needed him to move on. The content was another matter. Her husband was plotting with the girlfriend to set her up for criminal charges so he could take their child.
He described planting drugs in her car and making sure the police found them. She did not want to involve the police, but we went in for an order of protection, and the texts came with us.
On the stand, he denied all of it and tried to keep the messages out of evidence. The court let them in.
The couple had linked the devices themselves, the wife installed no spyware, and all she did was read texts on her own iPad. This happens more than you would think.
Shared Phone Bills and Location Sharing
Even without touching a device, a spouse can learn a lot. Family plans put several lines on one account, so most couples share a phone bill, and no one on a shared bill has much privacy.
The bill lists every call and text, with the number, the date, and the time. Want to know who your spouse is texting at 3:00 a.m.? It is on the bill.
When a divorce begins, take your privacy back:
- Run Apple’s Safety Check or Google’s Security Checkup. One screen shows everything shared with your spouse and lets you end it, device by device.
- Move your phone to its own account, so your calls and texts no longer show up on a shared bill.
- Turn off location sharing in Find My, Google Maps, and any family locator app, and when one of you moves out, go back through every place your location is still shared.
Does Spying Evidence Hold Up in Illinois Divorce Court?
Information your spouse sends you directly is a different story. In court, anything either of you say could be deemed a “party admission” and could come into evidence. Voicemails can also be fair game. So do not get mad and leave a string of nasty voicemails on your ex’s phone. Think before you speak and remember that anything you say or write could be used against you.
Then, of course, my favorite spy tool is Facebook. You cannot imagine the posts people make there. And it is not really spying when you are posting sensitive information to the whole world. If you have a custody case and a drinking problem, it is not smart to post pictures of yourself winning a beer-drinking contest. True story! I still marvel at that one. The same goes for Instagram, TikTok, and every messaging app. In parenting disputes, public posts routinely become digital evidence in an Illinois custody case.
TIP: During a divorce or custody case, do not post images or comments that can be used against you.
What If Your Spouse Is Spying on You?
Our firm dealt with a case where the husband placed spyware in his wife’s bedroom. She never saw it there. His comments about her private life told her something was wrong. She hired an expert to sweep for a device. Once found, the husband denied putting it there. But devices like these carry the name of the company and a serial number. A subpoena to the company revealed who purchased the device: the husband. You would generally be allowed to surveil your own home, so there was seemingly no problem at first. Once he moved out and kept surveilling, the same device became a violation, due to what he captured with it.
If you learn that your spouse has gone through your computer or email, let your divorce attorney know right away. There are certain civil remedies to which you may be entitled, and your attorney can file the petitions and motions that ask the court for them. Save any evidence you have of the eavesdropping or snooping and do not confront your spouse about it first. Preserved evidence keeps its value; a confrontation usually ends it.
Your own phone will help you here. Watch for:
- An alert that an unknown AirTag is traveling with you
- A phone battery that drains faster than it should
- A sign-in on an account you do not recognize
When the concern is safety rather than evidence, an order of protection can often bar the surveillance directly. That remedy is not limited to married couples. Illinois extends it to people who live together, who have dated, or who share a child.
Talk to a Divorce Lawyer Before You Snoop
Spying can be a murky area and before you engage in it, you should consult with someone. You are allowed to have a friend sit right behind your spouse and his girlfriend at a restaurant to overhear what they say. (How can that be considered eavesdropping?) Yet recording that same conversation can be a problem. Before you snoop, make sure that your activity falls within the bounds of the law. It is a lot easier to guide you before you engage in an activity that could lead to the exclusion of the evidence you worked so hard to get. More importantly, your lawyer’s advice can also keep you out of criminal trouble. And by all means, if you do not have an experienced family law attorney to consult with, be sure to get one. Going it alone can have devastating and lasting consequences. Contact Anderson Boback & Marshall to speak with one of our experienced lawyers about your case and any evidence question before you act.
Spying and Divorce Evidence in Illinois: Frequently Asked Questions
Is it illegal to record my spouse in Illinois?
Yes, if it is a private conversation and recorded without their consent. Illinois requires the consent of every party to a private conversation. Secretly recording your spouse is a crime, not just a divorce problem. The recording is also generally barred from evidence. At Anderson Boback & Marshall, we see these recordings hurt the recorder more often than the recorded.
Can I put a GPS tracker or AirTag on a car we both drive?
The safe answer is no, not without legal advice first. Illinois ties the crime to the consent of the vehicle’s registered owner, lessor or lessee. The registration matters more than whose money bought the car. If the car is registered to your spouse, placing a tracker can be charged as a Class A misdemeanor.
Can my spouse use my texts against me in court?
Yes. Anything you send your spouse directly, texts, emails, and voicemails, could be deemed a party admission that an Illinois court can hear. Assume every message you write during a divorce will be read in front of a judge, and write accordingly.
Can secretly recorded conversations be used in divorce court?
Generally no. Illinois courts suppress recordings made without consent, and the person who made them could face sanctions and criminal exposure on top of losing the evidence. Narrow exceptions exist, which is why you should ask your attorney before you record anything.
Can I check my spouse’s location through a shared account or Find My?
If the sharing was set up together and never turned off, viewing it is generally not spying. You both agreed to it. The gray zone arrives when someone re-enables sharing secretly or adds tracking the other person never knew about. An Illinois court looks at what each spouse actually agreed to.
What should I do if I find a tracking device or AirTag?
Do not destroy it and do not confront your spouse. Photograph it where you found it, keep it, and tell your family law attorney. The maker’s records can show who bought it, as they did in a case our firm handled. If you feel unsafe, the discovery can possibly support an order of protection.
