Heyl Royster

Michael Denning

Office Managing Partner & Shareholder
Rockford, IL

Joined Firm in 2004

Mike focuses on a client-first approach to the practice of law that combines a strong work ethic and a deep understanding of complex medical issues with a proven ability to advocate for the firm’s clients professionally and practically.

  • Rated AV Preeminent® Peer Review Rating by Martindale-Hubbell®
  • Member of Illinois Supreme Court Committee on Jury Instructions in Civil Cases
  • Chair of Medical Malpractice Group
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Michael Denning

Attorney in Rockford, IL

Mike is an experienced, successful lawyer who has tried many cases to verdict and represented professionals in all aspects of complex malpractice litigation, concentrating on the defense of medical malpractice and nursing home claims. Mike regularly defends physicians, clinics, and hospitals in professional liability and institutional negligence claims involving significant injuries or death. Additionally, he handles a myriad of administrative issues for long-term care facilities, including involuntary discharge proceedings, licensure issues, fraud and abuse claims, and other litigation.

Mike has successfully tried many cases to verdict in Illinois and Iowa and has represented the firm's clients in complex malpractice litigation for many years. Mike enjoys the challenge of partnering with his colleagues and trying these cases to verdict. He frequently speaks and writes on topics involving jury trials and trial strategies and has published articles in local, state, and national publications. He was named one of the "40 Under Forty" attorneys to watch in Illinois by the Law Bulletin Publishing Company and rated an AV Preeminent by Martindale-Hubble.

While in law school at Northern Illinois University, Mike served as Editor-in-Chief of the Law Review. He began his legal career with the firm as a Summer Associate in the Peoria office. After completing a judicial clerkship with Illinois Appellate Court Judge Tom M. Lytton in 2004, Mike joined the firm's Rockford office. He is licensed to practice in Illinois, Iowa, and Wisconsin.



J.D., Northern Illinois University, cum laude

B.S., Bradley University, Business Administration

Licensure(s) and Admission(s)

State Courts of Illinois

State Courts of Iowa

State Courts of Wisconsin

United States District Court for the Eastern District of Wisconsin

United States District Court for the Northern District of Wisconsin

United States District Court for the Western District of Wisconsin

United States Supreme Court

Professional Affiliations

American Bar Association

Defense Research Institute

Federation of Defense & Corporate Counsel

Chair, Professional Liability Section

Editor, Professional Liability Section Newsletter

Illinois Defense Counsel

Illinois State Bar Association

Professional Liability Defense Federation

State Bar of Wisconsin

Winnebago County Bar Association

Community Involvement

American Red Cross, Rock River Chapter, Former Chair, Board of Directors

Belvidere Community School District 100 Foundation for Excellence in Education, Board Member

Northern Illinois University College of Law, Alumni Council

Rockford Business College, Former Instructor


  • Obtained a defense verdict for a bariatric surgeon following a jury trial in which Plaintiff alleged that the surgeon’s reversal of a prior bariatric surgical procedure, hernia repair and fundoplication led to splenic rupture, uncontrolled bleeding and 2 emergency surgeries. During the first emergency surgery, the surgeon encountered 4 liters of blood in the abdominal cavity. Plaintiff asserted liability on a traditional theory of negligence as well as under the doctrine of res ipsa loquitur. The jury quickly returned a complete defense verdict on behalf the firm’s clients.

  • Obtained a defense verdict for a colorectal surgeon following a jury trial in which the plaintiff asserted that during colonoscopy, the surgeon perforated the plaintiff's colon and failed to find or repair the hole, which during subsequent emergency surgery was found to be 1.5 cm. The plaintiff was given an ileostomy, had lengthy hospitalizations, required additional surgeries, and incurred nearly $130,000 in medical bills. After deliberating for less than 45 minutes, the jury returned a defense verdict.

  • Successfully defended a family practice physician in a wrongful death lawsuit brought by the widow and four children of a 45 year-old non-smoker. The lawsuit claimed that the family practice physician failed to diagnose the patient/decedent’s lung cancer. Based on the patient’s clinical presentation, pulmonary function test, and response to asthma medications, the defendant physician diagnosed the patient/decedent with asthma in January of 2009. In January of 2010, the patient went to the Mayo Clinic on self-referral and was diagnosed with stage IV lung cancer with metastasis to the brain. He underwent chemotherapy and radiation but ultimately passed away in 2015 as a result of lung cancer. Plaintiff sought recovery for survival damages, loss of consortium and wrongful death, and at the end of a more than two-week trial, plaintiffs asked for an itemized verdict of more than $10 million. The jury deliberated for less than two hours before returning a verdict for the defense.

  • Obtained defense verdict for general surgeon following a jury trial in which plaintiffs alleged that the surgeon failed to find and repair a transaction or injury to the patient's small bowel following performance of emergency appendectomy leading to sepsis, peritonitis, medically-induced coma, placement of ileostomy and the development of significant and permanent gastrointestinal issues. Plaintiffs sought recovery for substantial medical bills, as well as pain and suffering, disfigurement, loss of normal life, and loss of consortium.
  • Secured defense verdict following a lengthy jury trial for a pediatrician in DeKalb County alleged to have failed to diagnose undescended testicles in a child from birth to age 15 months. Plaintiff's claimed damages included loss of one testicle, loss of normal life and emotional distress, and claims of infertility in adulthood.
  • Obtained directed verdict in a jury trial on behalf of a general surgeon who was alleged to have improperly operated on a patient suffering from an apparent bile leak and associated symptoms caused by a retained gallbladder following cholecystectomy performed by another surgeon.
  • Obtained a defense verdict for the defendant surgeon after a jury trial in which the plaintiff alleged that the surgeon failed to remove her gallbladder entirely during a cholecystectomy.
  • Represented the defendant's orthopedic surgeon at a jury trial in the successful defense of allegations that the doctor improperly cast the plaintiff's both-bone forearm fracture, allegedly causing permanent deformity and loss of motion.
  • Represented OB-GYN physician at a jury trial in the successful defense of the plaintiff's allegations of bowel injury during the closure of a surgical wound after the performance of tubal ligation.
  • Represented a radiation oncologist at trial in the successful defense of the plaintiff's claims that in treating her cancer, the oncologist administered too much radiation, causing insufficiency fractures in her bones and resulting in her death.
  • Eckburg v. Presbytery of Blackhawk of Presbyterian Church (USA), 396 Ill. App. 3d 164, 918 N.E.2d 1184 (2d Dist. 2009) – Represented rural landowner in the appeal of a case alleging serious injury and wrongful death to plaintiffs, a motorcycle rider, and his passenger wife, resulting from a tree falling onto a state highway. The court affirmed the lower court's dismissal of the case. In a second appeal (Eckburg v. Presbytery of Blackhawk of Presbyterian Church (USA), 2011 IL App (2d) 110284-U, the Appellate Court ruled that the landowner could not be held liable for damage caused by falling branches or trees that abut private property but are physically located on state's right-of-way and exclusively under state's control.
  • Lorenz ex rel. Lorenz v. Herrera, 362 Ill. App. 3d 1171, 842 N.E.2d 770 (2d Dist. 2006) – Represented defendants/appellants Sheriff and Sheriff's Department in an appellate case which established that the proper venue for personal injury action against the deputy sheriff is the county in which the sheriff's office is located, not the plaintiff's county of residence.



Timeline of Medical Malpractice Litigation,” Courtroom Sciences Litigation Psychology Podcast – Episode #211 (2024)

“A Picture Is Worth 1,000 Words: The Use of Technology at Trial,” Heyl Royster's 33rd Annual Claims Handling Seminar (2018)

“Understanding Recoverable Damages: Double Dipping by Plaintiffs,” Heyl Royster's 32nd Annual Claims Handling Seminar (2017)

“I Always Feel Like Somebody’s Watching Me: An Eye on the Inside of Nursing Homes,” Heyl Royster's 31st Annual Claims Handling Seminar (2016)

“Can the Affordable Care Act Make Future Medical Care in Litigation More Affordable?,” Heyl Royster's 31st Annual Claims Handling Seminar (2016)

“Using Technology at Trial,” Winnebago County Bar Association Trial & Appellate Section CLE (2016)

“What You Need to Know About Nursing Home Care Liability,” Heyl Royster's 30th Annual Claims Handling Seminar (2015)

“Using Technology in the Courtroom,” Winnebago County Bar Association Trial & Appellate Section CLE (2015)

“How to Handle the Midnight Call and The Building Blocks of an Effective Defense,” Heyl Royster 29th Annual Claims Handling Seminar (2014)

“Civil Procedure Update,” Illinois Association of Defense Trial Counsel (2013)

“You’ve Been Served: How to Help Your Organization Understand and Defend a Lawsuit,” St. Mary’s Occupational Health & Streator Chamber of Commerce (2013)


Eavesdropping – Easier Than Ever!,” Illinois Defense Counsel Quarterly (2018)

 Pro Se Complaints for Wrongful Death or Survival Damages: Void or Amendable?” FDCC Insights, A Journal for Defense and Corporate Counsel (2017)

"An Overview of the Affordable Care Act’s Potential to Mitigate Future Damage Claims," Heyl Royster, Medicolegal Monitor, Fourth Quarter (2015)

"Survey of Civil Practice Cases," Illinois Association of Defense Trial Counsel's 2013 Survey of Law (2014)

"Liquor Liability: Social Hosts and Other Issues," 26th Annual Claims Handling Seminar (2011)

"Illinois Courts Expand, Then Narrow Validity of Arbitration Agreements in Nursing Home Litigation," IDC Defense Update, Vol. 12, No. 14 (2011)


  • Emerging Lawyer by Law Bulletin Media℠, 2016 -2017
  • 40 Under Forty Attorney to Watch by Law Bulletin Media
  • Best Lawyer in AmericaTM by The Best Lawyers in AmericaTM – Medical Malpractice Law – Defendants
  • Leading Lawyer by Law Bulletin Media
  • Rated AV Preeminent® Peer Review Rating by Martindale-Hubbell®
  • Super Lawyer by Super Lawyers®
  • Super Lawyer Rising Star by Super Lawyers®
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