Devon Petersen

Devon Petersen is a partner and criminal defense attorney at Fleener Petersen, LLC, representing clients in Wyoming and Colorado. He focuses his practice on felony criminal defense, appeals, and post-conviction matters. He has represented thousands of defendants and has handled serious allegations involving homicide, sexual assault, aggravated assault, robbery, drug offenses, property crimes, and other felonies. His approach combines courtroom preparation with detailed legal research, persuasive writing, and focused appellate advocacy.

Devon earned his bachelor’s degree in history from Princeton University in 2003. He earned his J.D. from the University of Wyoming in 2008, where he graduated near the top of his class. He began his legal career clerking for Judge Norman E. Young in Wyoming’s Ninth Judicial District. He later spent six years as a public defender, where he handled complex cases and built extensive trial experience. He is licensed in Wyoming and Colorado, and he is admitted before the U.S. District Court for the District of Wyoming and the U.S. Supreme Court.

Devon has tried more than 30 cases before juries, and he has secured acquittals in numerous serious criminal matters. He has obtained favorable verdicts in cases involving second-degree murder, manslaughter, vehicular homicide, sexual assault, aggravated assault, robbery, theft, child abuse, and other charges. He has also argued eight cases before the Wyoming Supreme Court. His appellate work has helped establish important precedents involving criminal law and juvenile justice.

Devon Petersen also contributes to Wyoming’s legal community through teaching, speaking, and professional service. He has served as an adjunct professor at the University of Wyoming, where he taught Trial Practice, Civil Pretrial Practice, and Bar Exam Preparation. He has also lectured at the university’s Summer Trial Institute and presented on jury selection, cross-examination, opening statements, and self-defense cases. His service includes membership on the Wyoming Trial Lawyers Association board, reflecting his commitment to advocacy and continued professional education.

Law Office Affiliations

• Partner, Fleener Petersen, LLC
• Member, Wyoming Trial Lawyers Association

Licensed State

• Wyoming
• Colorado

Education

• University of Wyoming
  Juris Doctor (JD)
• Princeton University
  Bachelor’s Degree