Skip to Main Content

Joan “Cassie” Mathias

Joan (“Cassie”) Mathias joined the Maryland Office of the State Prosecutor in 2023.  She is a Senior Assistant State Prosecutor responsible for the investigation and litigation of political corruption and public official misconduct matters throughout the state, specializing in those cases involving election integrity.

Prior to this position, Cassie spent six years at the Maryland U.S. Attorney’s Office.  In the U.S. Attorney’s Office, she investigated and prosecuted cases involving violent and organized crime and money laundering.  She also led the Bank Secrecy Act Task Force.  She was awarded the Deborah A. Johnston Profile in Courage Award, which is presented to one or more Assistant U.S. Attorneys who demonstrate extraordinary courage and commitment to duty while representing the United States of America. 

In addition, Cassie served as an Assistant Attorney General in the Organized Crime Unit of the Office of the Attorney General of Maryland.  Cassie also spent time in Washington D.C. serving as an associate in King & Spalding’s Government Investigations and Special Matters unit.  

She graduated summa cum laude from the University of Pennsylvania and received her J.D. from Harvard Law School.