Untress “Trez” Quinn is a seasoned trial lawyer, focusing his practice on the defense of medical malpractice and other catastrophic loss lawsuits. He has defended multiple complex litigation cases in both state and federal courts involving civil rights, product liability, medical malpractice and wrongful death claims.

Untress’ defense of high stakes litigation matters in both Illinois and Missouri have included matters involving mental health/suicide, neurological, obstetrical, neonatal, pediatric, cardiothoracic, gastroenterological and other traumatic injuries and losses. He also has specific experience defending medical professionals in matters alleging federal Section 1983 violations.

Untress leverages his experience as a registered nurse, along with experience in both direct patient care and health care administration, to skillfully counsel his clients through difficult health care-related matters.

His wide-ranging experience and abilities include representing health care providers in not only litigation matters, but also internal investigations involving:

  • Peer Review Hearings
  • Licensure denial or revocation
  • CMS suspensions or revocations
  • Administrative actions
  • Investigative demands received from federal and state agencies

Further, Untress is a frequent speaker at industry events across the nation, where he educates his clients and other professionals on various legal topics, and further advocates on their behalf.


Prior to joining Armstrong Teasdale, Untress spent roughly 15 years in private practice at St. Louis area law firms. In his most recent role, he served as team leader for his prior firm’s Correctional Medicine industry team where he managed and supervised a team attorneys and paralegals.

Untress was a registered nurse for more than 10 years, and has been involved in the health care industry for over 25 years in total. Untress has extensive experience in both medical and surgical settings, including interventional radiology, ventilator rehabilitation, emergency room and cardiothoracic and neurological intensive care units. In addition to providing direct patient care, he served as a director of medical-surgical services, as well as a supervisor of interventional radiology and health care administrator. Untress also served as an adjunct professor at a local university teaching a class involving the interplay between health care and the law. Untress’ extensive medical knowledge and experience are assets he uses in the successful representation of his clients.

Untress was also a member of the U.S. Air Force Reserves for 13 years, where he achieved the rank of first lieutenant and was awarded the Meritorious Service Award. He was an honor graduate at the 3790th Medical Service Squadron for Medical Service Specialists at Sheppard Air Force Base in 1990.


  • Saint Louis University School of Law  (J.D., 2006)
    • Certificate in Health Law
    • Health Law Association
    • Black Law Student Association
  • National Louis University  (B.S., 2001)
    • Management
    • Dean’s List
    • Student Body Representative
  • Lutheran Medical Center School of Nursing  (R.N., 1994)
    • Salutatorian
    • Dean’s List
    • Student Body Representative
    • Alumni Academic Scholarship


  • Illinois
  • Missouri
  • U.S. District Court, Southern District of Illinois
  • U.S. District Court, Central District of Illinois
  • U.S. District Court, Eastern District of Missouri

Professional Activities

  • Bar Association of Metropolitan St. Louis (BAMSL) (Board Secretary, 2021-2022)
  • Illinois Association for Defense Trial Lawyers, Diversity Committee Chair
  • St. Clair County Bar Association
  • American Bar Association
  • American Health Lawyers Association
  • U.S. District Court for the Southern District of Illinois (Merit Retention Panel, 2012; Magistrate Judge Selection Committee, 2018)
  • Attorney Registration and Disciplinary Commission of the Supreme Court of Illinois (Hearing Board Member)

Charitable and Civic Involvement

  • St. Clair County Child Advocacy Center (Member, Board of Directors)
  • Illinois Center for Autism in Fairview Heights, Illinois (Past Member, Board of Directors)
  • Student Nurse Achievement Program (SNAP) at Southern Illinois University (Past Member)
  • Illinois State Senator James F. Clayborne, Jr., Mentor Program (Past Mentor)
  • Office of the Inspector General / Illinois Department of Human Services Quality Care Board (Past Member)


  • Selected to The National Black Lawyers Top 100 in 2015
  • NAACP’s 54th Freedom Fund Awards for Excellence in Law
  • Leading Lawyer in the categories of Employment Law: Management; Medical Malpractice Defense Law; Personal Injury Defense Law: General; and Product Liability Defense
Contact Us
  • Worldwide
  • Boston, MA
  • Denver, CO
  • Edwardsville, IL
  • Jefferson City, MO
  • Kansas City, MO
  • Las Vegas, NV
  • London, England
  • New York, NY
  • Philadelphia, PA
  • Princeton, NJ
  • Salt Lake City, UT
  • St. Louis, MO
  • Wilmington, DE
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800 Boylston St.
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Kansas City, MO
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3770 Howard Hughes Parkway
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919 Third Ave., 37th Floor
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Philadelphia, PA
2005 Market Street
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Philadelphia, PA 19103
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Princeton, NJ
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Salt Lake City, UT
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St. Louis, MO
7700 Forsyth Blvd.
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Wilmington, DE
300 Delaware Avenue
Suite 210
Wilmington, DE 19801
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