Brett Mares
Attorney in Chicago, IL
Brett Mares, our colleague, our dear friend, and our Chicago Partner, lost his many years battle with cancer yesterday, March 2, 2025, at age 40. His wife, Kari, reports that no one fought harder and that by the time he moved to hospice, he truly had nothing left and the end was peaceful. She is grateful that he doesn’t hurt any more. Brett, like most challenges he faced, tackled his diagnosis and 8+ years of treatment with strength, intelligence, eternal optimism, and remarkably good cheer. He did that for us because he wanted us to be comfortable and to have hope. He did that for Kari and his two young boys, Sam and Charlie, because he wanted to cherish every second he had with them. His heart belonged to his family, and we were blessed to hear him speak of them and the “dad life” life he embraced and valued above all else.
For most of his battle, he remained engaged and productive in our work, even earning partnership, and only recently moving to disability status as his treatment became more challenging. Brett started at our law firm in the Edwardsville office in 2011 and relocated to Chicago to help us build that office. Aside from his aptitude and skills as an attorney (of which he had in spades), Brett was a stabilizing force among our younger lawyers providing mentorship, guidance, and an exemplar of the Heyl way of practicing law. He handled a wide breadth of practice areas and matters for our clients. He loved being an attorney, and more importantly, he loved being an attorney with us. He served as our firm’s in-house ethics counsel and his compass served to keep us headed in the right direction. Brett was a capable and accomplished litigator, and it would be impossible to detail his many successes over the years. Brett and his contributions will truly be missed.
He was truly beloved in the office never taking himself – or any of us, frankly – too seriously. Brett DID, however, take seriously lunches. We will all cherish our time spent around the “front room” table during lunch with Brett. He introduced us to culinary hidden gems – one Mediterranean café famously accessed from the street only through a jewelry store or another famous sandwich that combined ALL of Thanksgiving dinner between bread. But mostly, Brett just enjoyed being with us, being part of something, and sharing time with us. We will be forever grateful for his presence, for his gifts of wit and humor though we often teased – and he actively embraced – the very real fact that he had the disposition of an 80 year old man trapped in the body of a millennial.
Brett was golden beyond measure and taken far too soon from us.
Practices
Credentials
Education
J.D., University of Minnesota School of Law
B.A., University of Illinois, History
Licensure(s) and Admission(s)
State Courts of Illinois
State Courts of Missouri
State Courts of Wisconsin
United States District Court for the Central District of Illinois
United States District Court for the Eastern District of Missouri
United States District Court for the Northern District of Illinois
United States District Court for the Southern District of Illinois
United States District Court for the Western District of Missouri
Professional Affiliations
Defense Research Institute
Community Involvement
Disaster Relief Volunteer Services, Founder
Results
- Won dismissal with prejudice for a student athletic association based on a lack of actionable involvement in an equipment failure case
- Settled an equipment failure case for less than ten percent of the plaintiff’s demand after uncovering evidence of a co-defendant’s culpability
Presentations/Publications
Presentations
“Contracts, Invoices, and Letters - Make Sure Your Documents Contain State of the Art Disclaimers and Other Smart Provisions,” Heyl Royster “Avoiding Litigation” Seminar, Rockford (2016)
Publications
"Consideration and Non-Compete Agreements: The State of the Law in Illinois," International Association of Defense Counsel Business Litigation Committee Newsletter (2017)
"Environmental Justice and the BP Deepwater Horizon Oil Spill," New York University Environmental Law Journal (2013)
"The Cemetery Oversight Act: What You Need to Know at the Local Level," Heyl Royster Governmental Newsletter (2013)
"Update: Medical Malpractice Caps," American College of Legal Medicine Q&A (2012)
"Update: Learned Intermediary Doctrine," American College of Legal Medicine Q&A (2012)
"Question: What Are the Results of Pharmacological Errors and How Do They Improve with the Use of Technology?," American College of Legal Medicine Q&A (2011)
"A Chip Off the Old Block: Familial DNA Searches and the African American Community," Minnesota Journal of Law & Inequality (2011)
Awards/Recognition
- Emerging Lawyer by Law Bulletin Media℠, 2018 – 2023
Updates
Public Profile
Brett Mares, our colleague, our dear friend, and our Chicago Partner, lost his many years battle with cancer yesterday, March 2, 2025, at age 40. His wife, Kari, reports that no one fought harder and that by the time he moved to hospice, he truly had nothing left and the end was peaceful. She is grateful that he doesn’t hurt any more. Brett, like most challenges he faced, tackled his diagnosis and 8+ years of treatment with strength, intelligence, eternal optimism, and remarkably good cheer. He did that for us because he wanted us to be comfortable and to have hope. He did that for Kari and his two young boys, Sam and Charlie, because he wanted to cherish every second he had with them. His heart belonged to his family, and we were blessed to hear him speak of them and the “dad life” life he embraced and valued above all else.
For most of his battle, he remained engaged and productive in our work, even earning partnership, and only recently moving to disability status as his treatment became more challenging. Brett started at our law firm in the Edwardsville office in 2011 and relocated to Chicago to help us build that office. Aside from his aptitude and skills as an attorney (of which he had in spades), Brett was a stabilizing force among our younger lawyers providing mentorship, guidance, and an exemplar of the Heyl way of practicing law. He handled a wide breadth of practice areas and matters for our clients. He loved being an attorney, and more importantly, he loved being an attorney with us. He served as our firm’s in-house ethics counsel and his compass served to keep us headed in the right direction. Brett was a capable and accomplished litigator, and it would be impossible to detail his many successes over the years. Brett and his contributions will truly be missed.
He was truly beloved in the office never taking himself – or any of us, frankly – too seriously. Brett DID, however, take seriously lunches. We will all cherish our time spent around the “front room” table during lunch with Brett. He introduced us to culinary hidden gems – one Mediterranean café famously accessed from the street only through a jewelry store or another famous sandwich that combined ALL of Thanksgiving dinner between bread. But mostly, Brett just enjoyed being with us, being part of something, and sharing time with us. We will be forever grateful for his presence, for his gifts of wit and humor though we often teased – and he actively embraced – the very real fact that he had the disposition of an 80 year old man trapped in the body of a millennial.
Brett was golden beyond measure and taken far too soon from us.
