Mary Kay Morrissey focuses her practice in the areas of labor and employment litigation, including sexual harassment, sexual discrimination, age discrimination, disability discrimination, wage and hour compliance and class and collective action, in addition to commercial litigation, professional malpractice litigation, and managed health care litigation.

Ms. Morrissey began her professional career in 1987 working in the area of commercial litigation for one of the largest and most prestigious firms in Oklahoma. In 1989, Ms. Morrissey returned to Illinois. Throughout her 20 years of practice, Ms. Morrissey has amassed a broad range of experience in trial work and appellate practice in both federal and state courts.

In 1997, Ms. Morrissey left private practice to go in house with Ameritech’s Litigation Department, where she successfully defended Ameritech in a number of commercial class action lawsuits. While at Ameritech, Ms. Morrissey also defended Ameritech in numerous employment actions, involving sexual harassment, sexual discrimination, age discrimination and disability discrimination issues.

Ms. Morrissey has been back in private practice since June 2001, once again concentrating her practice in the areas of commercial litigation and professional malpractice litigation, representing both corporations and individuals.

Ms. Morrissey received her BS from Marquette University in 1984, and her JD from the University of Tulsa Law School in 1987. While in law school Ms. Morrissey was on the Dean’s Honor Roll, received academic law school scholarships, and was invited to be a member of the University of Tulsa’s Law Journal. While a member of the Law Journal, Ms. Morrissey authored The Duties of Concurrent Owners of Oil and Gas Interests: Tenneco Oil Co. v. Bogart, 22 Tulsa Law Journal 563 (1987).


  • Illinois
  • Oklahoma
  • U.S. District Court
    • Northern District of Illinois
    • Northern District of Oklahoma
  • U.S. Court of Appeals
    • Seventh Circuit
    • Tenth Circuit


  • University of Tulsa Law School – J.D.
  • Marquette University – B.S
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