Jonathan had a 28 year career as a litigator in Manhattan, including as an Assistant District Attorney under acclaimed District Attorney Robert M. Morganthau (1990-1995), as an associate, then partner in a midtown Manhattan law firm doing health care related litigation (1995-1998,1998-2000), and as a founding member of law firms Jonathan Ginsberg & Associates (2000-2005) and Mangan Ginsberg (2011-2017). During that time, he tried and participated in trying over 50 cases to verdict and in many hundreds of settlements before judges, juries, and arbitrators in courts in New York, in New Jersey, in criminal and civil matters ranging from homicides to 38 U.S.C. Section 1983 civil rights matters, to tort cases involving catastrophic injuries with seven figure damages, an $8 million commercial dispute involving dissolution of a law firm, and assisted in obtaining vacatur of a $250 million dollar default judgment against an individual shareholder in Texas of an export business located in the Middle East.

Jonathan has performed health care oversight on a broad variety of issues including quality, compliance, confidentiality, privilege, and privacy on a local, regional and national scale since 2018. He began serving as a mediator in 2023.

For academics he graduated Binghamton University (B.A., 1987) with honors, and with academic honors in English, and The George Washington University Law School (J.D., 1990), was a Trustee Scholar in 1988, and a member of the District of Columbia Circuit Court Inns of Court from 1988 to 1989.

As a mediator he prides himself on having the maturity, experience and discretion to serve as a neutral arbiter of critical disputes. He has the courtroom and appellate experience to understand the challenges litigators face on either side of the bar, the risks and uncertainties of contested, public litigations, and the benefit that mediation can provide including certainty, finality and efficiency.