Marcus' passion for criminal law began as an intern for the Plymouth County District Attorney's Office. During his tenure, Marcus developed a working knowledge of court, prosecution, and police procedure. He expanded his knowledge of the subject while studying Criminal Justice at Bridgewater State University, where he graduated compiling multiple academic honors. He then attended University of Massachusetts School of Law as a recipient of an academic scholarship. During his time at UMass Law, Marcus was involved in several student organizations, including the Criminal Law Society, which would often educate general public about the institutions of and new developments in criminal law. Following his graduation from UMass Law, Marcus was admitted into the Massachusetts Bar as a licensed attorney. 

Upon his admission to the Massachusetts Bar, Attorney Ferro launched his own solo practice, The Law Office of Marcus D. Ferro as an affiliate of the Justice Bridge Legal Center in Downtown New Bedford. To this day, Attorney Ferro continues to provide strong and effective legal solutions to the residents of the Southcoast and beyond.