About Jonathan F.
Jonathan F. Marshall is a New Jersey lawyer whose career spans both prosecution and defense. He trained as an accountant before turning to law, and he has maintained a steady presence in the state’s criminal courts for decades.
Marshall earned a B.S. in Accounting and Finance from Rider University before attending Seton Hall University School of Law, where he completed his legal studies in 1989. His academic background in accounting and finance informs how he evaluates evidence and builds records-based defenses in complex hearings.
He spent the mid-1990s in municipal prosecution. In 1995 he served as a prosecutor for the Township of Hazlet and, two years later, for the Borough of Matawan. Those years in the prosecutor’s office offered him regular courtroom time and a close view of how municipal cases are prepared and argued.
After moving into private practice, Marshall established offices under his own name and under the Marshall Criminal Defense & DWI Lawyers banner. He represents clients throughout New Jersey on criminal charges and driving-while-intoxicated matters. His practice profile reflects both trial experience and specific training in DWI procedures.
Marshall holds certifications in Alcotest breathalyzer operation from Draeger Safety and in Standardized Field Sobriety Testing through the National Highway Traffic Safety Administration. He began his membership in the Association of Criminal Defense Lawyers of New Jersey in 2008 and joined the National College of DUI Defense in 2013. Those memberships connect him to peers who handle technical and constitutional issues arising in impaired-driving cases.
Colleagues and court records show that he often brings technical questions about testing devices and roadside procedures into case strategy. He combines that technical awareness with the practical skills developed during his years as a municipal prosecutor and as a defense lawyer. His work touches on pretrial motions, negotiated resolutions in appropriate cases, and contested trials when clients choose to proceed to court.
Marshall maintains a private practice under the Law Offices of Jonathan F. Marshall and related firm names, serving clients across New Jersey. He continues to handle criminal defense and DWI matters, drawing on his background in accounting, municipal prosecution experience, and specific DWI training in breath testing and field sobriety procedures. His current practice focuses on criminal defense and DWI representation in New Jersey courts.
