Who is at Fault in a Car Accident in Illinois?
Getting into a car accident can turn your whole day around. Beyond the initial shock and damage, you’re left trying to figure out who’s at fault—and what that means for you. In Illinois, fault matters. It determines who pays for the damage, how much you might get, and if you even have a case. It’s not always clear cut and it helps to know how the state laws work. If you’ve been in a crash and have questions about what comes next, Attorney Michael J. Brennan is here to help you make sense of it all and protect your rights.
Illinois Is a Comparative Fault State
When it comes to car accidents in Illinois, fault isn’t always black and white. The state uses a system called modified comparative negligence. That means more than one person can be held responsible for the same accident, and each party’s share of the blame affects what they can recover.
If you’re found to be less than 51% at fault, you can still pursue compensation. But the amount you get will be reduced by your percentage of fault. For example, if you were 20% responsible for the crash, whatever you’re awarded will be reduced by that same 20%.
But if you’re found to be 51% or more at fault, you won’t be able to collect from the other party. This is why it’s so important to document the accident and push back if the insurance company tries to put more fault on you than you deserve. When fault is shared, even a small difference in percentages can make a big difference in the outcome of your case. That’s why it helps to have someone in your corner who knows how this works and can protect your interests throughout.
How Fault is Determined
In Illinois, figuring out who caused a car accident involves more than just pointing fingers. Several factors are reviewed to piece together what actually happened and who’s legally responsible.
Police reports are often the starting point. Officers on the scene will document what they observed, take statements, and sometimes issue citations. While not final proof, that report can strongly influence how insurers and attorneys view the case.
Insurance companies also do their own digging. They’ll look at photos, damage reports, and any available video footage. Eyewitness accounts can help fill in the gaps, especially when the drivers tell different stories.
Traffic laws play a big role, too. Running a red light, failing to yield, or speeding can quickly shift blame. And in many cases, fault is split between drivers, which is where Illinois’ comparative fault rules come into play. The more evidence you have on your side, the better your chances of making a strong claim.
Why Legal Help Can Make a Difference
After a car accident, trying to do it all on your own can be overwhelming. Between insurance adjusters, medical bills and who was at fault, it gets confusing fast. Even when insurance companies seem helpful at first, their main goal is to pay out as little as possible.

This is where having a lawyer on your side can really help. An experienced attorney knows how to review all the details of your case, from police reports to witness statements and accident scene photos. They know how to challenge any attempt to unfairly blame you or reduce the value of your claim.
Legal help matters when it comes to deadlines and paperwork too. A missed form or an overlooked detail can hurt your ability to get full compensation. If you’re dealing with injuries, missed work or growing stress after a crash, having someone who knows the process can make all the difference in getting a fair outcome.
Speak With an Illinois Car Accident Lawyer Today
If you’ve been in a car accident and don’t know what to do, talking to an attorney is a good first step. Illinois law can be complicated when it comes to fault and insurance and the decisions you make early on can have long lasting effects. Whether the accident seemed minor or left you with serious injuries, it’s good to have someone who knows how the system works and will look out for you.
A conversation with an experienced Illinois car accident lawyer can give you clarity and help you figure out the next steps. Contact Attorney Michael J. Brennan for a free consultation and get the clarity and support you need to move forward with confidence.