Ryan D. Stys

Ryan Stys is a former military prosecutor and state prosecutor with extensive trial experience. As a trial lawyer at DeSisto Law, Ryan represents municipalities across Rhode Island in civil litigation.

Upon graduating law school, Ryan served on active duty as an officer and judge advocate in the United States Marine Corps. While on active duty, Ryan served as a prosecutor and command legal advisor. As a prosecutor, Ryan prosecuted numerous contested jury trials spanning a wide range of crimes including sexual assault, drug distribution, larceny, and various financial crimes. Ryan was also appointed as a Special Assistant U.S. Attorney for the Southern District of California where he prosecuted numerous crimes committed by civilians in federal jurisdiction. As a command legal advisor, Ryan provided pre-deployment training and instruction to multiple Marine Corps commands on various legal issues related to the law of armed conflict.     

In 2013, after being honorably discharged from active duty, Ryan was appointed as a Special Assistant Attorney General where he served as a criminal prosecutor in the Rhode Island Department of Attorney General. As a state prosecutor, Ryan prosecuted major felony cases involving homicide, robbery, child molestation, possession and production of child pornography, public corruption, and complex financial and internet crimes. Ryan also served as the State’s representative in Rhode Island’s establishment of its Veteran’s Treatment Court.  

Since 2013, Ryan has continued to serve as an Officer in the Marine Corps Reserve. In the Marine Corps Reserve, Ryan has served as a Staff Judge Advocate and Civil Affairs Officer. Currently, Ryan serves as a Regional Judge Advocate where he trains and advises commands on various legal issues including command investigations, administrative law, rules of engagement, and the law of armed conflict. Ryan has represented servicemembers at courts-martial, boards of inquiry, and administrative hearings. 


  • Naval Justice School, Judge Advocate Certification, (2010)
  • JD, Western Michigan University Cooley Law School (2008)
  • BS, University of Hartford ( 2004)

Court/Bar Admissions

  • Rhode Island
  • District of Columbia
  • United States Court of Appeals for the Armed Forces
  • United States District Court; for the District of Rhode Island
  • United States Court of Appeals for the First Circuit

Professional Affiliations

  • Volunteer, Operation Standdown Rhode Island

Publications and Speaking

  • Instructor, Civil Liability, Rhode Island Municipal Police Academy
  • Panelist, “Internet Use in Age of Anonymity: Managing your Cyber Trail,” Salve Regina University
  • Presenter, Crisis Intervention Training