Attorney Mark J. O’Brien - Miami, FL
Federal Criminal Defense Lawyers in Miami, FL
1001 Brickell Bay Drive Suite 2700 M-1 Miami, FL 33131
- Free Consultation
- 2 Super Lawyers®
-
17
Years
Experience
Miami Federal Criminal Defense Law Firm
Updated: 03/31/2026
Areas of Practice
- Federal Criminal Defense
- White collar crimes
- Sex crimes
- Child pornography
- Embezzlement
Litigation: 100%
Firm Information
Overview
Attorney Mark J. O’Brien is a criminal defense practice focused on nationwide federal criminal defense, as well as statewide criminal defense and criminal appeals.
Attorney Mark J. O’Brien is the founder and lead attorney. He represents clients in federal criminal courts across the United States and has built a strong reputation among federal judges and prosecutors for his skill and advocacy. A former Miami prosecutor, Mark brings over twenty-five years of experience to his practice and remains deeply committed to each case he handles, approaching every client with the same dedication and energy as when he began his career.
Attorney Victoria E. Hatfield serves as a key member of the practice, focusing on state and county criminal defense. She has secured numerous not guilty verdicts and has successfully argued motions to dismiss and suppress across a wide range of cases. Known for her tenacity and courtroom presence, Victoria is a strong and reliable advocate for her clients.
Olivia M. Goodman leads the firm’s criminal appellate work. She has handled over a hundred appeals, achieving consistent success in challenging convictions. Olivia takes a collaborative approach with clients and is recognized for her thorough analysis and strategic advocacy in appellate matters.
Attorney Mark J. O’Brien is supported by a dedicated team of paralegals, legal assistants, and private investigators, with the resources and commitment necessary to thoroughly investigate and aggressively defend every case.
Awards and Honors
Super Lawyers® Selectees
Attorney Mark J. O’Brien selected for a Super Lawyers® list
Languages
-
Spanish
Published Works
Articles
-
Are You Committing a Federal Crime by Playing Fantasy Sports?, 2015
Millions of people play daily fantasy sports, but is it legal? Criminal defense attorney Mark J. O'Brien is concerned that federal prosecutors may begin targeting it as a white collar crime.
Staff
- Jeanette Hevel, Legal Assistant, 8132634758
- Kiersten Richter, Legal Assistant
- Hana Shitama, Legal Assistant
- Denise Montero, Legal Assistant
Staff
- Jeanette Hevel, Legal Assistant, 8132634758
- Kiersten Richter, Legal Assistant
- Hana Shitama, Legal Assistant
- Denise Montero, Legal Assistant
Contact
Additional Florida Locations
Orlando, FL (205 miles)
121 South Orange Ave
Suite 1543
Orlando, FL 32801
Phone: 888-218-9483
Email: Send a message
Tampa, FL (Main Office, 205.6 miles)
511 West Bay Street
Suite 330
Tampa, FL 33606
Phone: 888-276-5244
Email: Send a message
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