• Mark A. Flessner
  • Corporation Counsel
Mark A. Flessner, Corporation Counsel

Mark A. Flessner is the Corporation Counsel for the city of Chicago.  He is a Chicago trial attorney with more than three decades of professional legal experience and most recently served as Partner at the firm Holland & Knight. 

He is well-versed in handling sophisticated matters across numerous industry sectors, having represented clients in many areas, including healthcare, retail, manufacturing, insurance and finance. He also has substantial experience investigating wrongdoing within the corporate world. Mr. Flessner has extensive trial experience, which includes bringing more than 50 cases to verdict and arguing more than 40 cases on appeal. He has advised litigation risk and assisted clients facing government scrutiny for criminal, civil and regulatory matters. Additionally, Mr. Flessner has represented clients facing complex commercial litigation, internal corporate investigations, grand jury inquiries and issues involving the Foreign Corrupt Practices Act (FCPA). 

Prior to entering private practice, Mr. Flessner was a federal prosecutor at the United States Attorney's Office in Chicago for 12 years. He led major investigations involving sophisticated and complex financial fraud. His prosecutions included public corruption, bank fraud, insurance fraud, securities fraud, white collar crime, gangs and narcotics cases. Mr. Flessner also has investigated international money laundering, terrorism and cases involving national security. 

Mr. Flessner has donated significant legal time to pro bono activities and was the pro bono partner for Holland & Knight’s Chicago office. He was a lead attorney on a death penalty habeas corpus petition in Alabama and on a high-profile immigration case in Chicago. He also served as a member of the Federal Defender Panel in the Northern District of Illinois, providing legal representation to the indigent.



DePaul University College of Law, J.D. 

University of Notre Dame, M.Div. 

University of Illinois at Urbana-Champaign, B.A.,

Political Science, with distinction


Honors & Awards 

  • The Best Lawyers in America guide, Criminal Defense: White Collar, 2016-2019
  • Illinois Super Lawyers magazine, 2018
  • Holland & Knight Public and Charitable Service All-Star, 2013-present
  • Heartland Alliance 16th Annual National Immigrant Justice Center Practitioner’s Award
  • Award for Excellence in Pro Bono Service, United States District Court for the Northern District of

Illinois and the Chicago Chapter of the Federal Bar Association

  • Recognition for Outstanding Contribution to Law Enforcement from:
  • Department of Justice
  • Federal Bureau of Investigation
  • Drug Enforcement Administration
  • Internal Revenue Service, Criminal Investigations Division
  • United States Postal Inspection Service
  • Chicago Police Department
  • Chicago Joint Task Force on Gangs
  • Director’s Award for Superior Performance, U.S. Attorney General, 1996



  • Federal Bar Association of Chicago, Board of Directors
  • Chicago State Foundation, Board of Directors
  • Chicago Police Accountability Task Force, January-April 2016
  • Just the Beginning Foundation, Board Member
  • Economic Club of Chicago, Member of Reception Committee
  • National Immigrant Justice Center Human Rights Awards, Chair, 2010-2014
  • Federal Bar Association, Federal Career Services Division, Chairman
  • Leading Lawyers Network, Peer Recommended 2013
  • Greater Chicago Food Depository Finance and Legal Community Fundraiser, former Chairman
  • Leadership Greater Chicago, Board Member, Fellow, 1995-1996
  • Chicago Council of Lawyers, former Board Member; former Ethics Committee Co-Chair
  • West Suburban Mass Transit District, Former Trustee
  • Appleseed Fund for Justice, Former Board Member

 Department Facts


 I Want To