We formed Mansfield, Rosenthal & Gautier LLP because our combined backgrounds would enable us to provide clients with a broad base of knowledge and skills. Together we have decades of experience working in law, private business, politics and government (local, state and federal). This experience translates into smart and cost-effective legal services for our clients, be they individuals or businesses. Our individual biographies are below.

Tom Mansfield

Tom’s background is varied, and includes business, law, government and politics. A graduate of Middlebury College and New York Law School (magna cum laude), Tom began his career working for the City of New York Law Department as an Assistant Corporation Counsel, where he earned his stripes as a litigator, and gained experience not only in municipal government, but in a wide variety of legal areas, including labor and employment, administrative and civil rights law.

After several years, Tom then caught the entrepreneurial bug and began a career running the first of two import/export businesses, the second of which led him to settle in the Hudson Valley town of Red Hook. As the successful business owner and manager of a small start-up and later a thriving mid-sized company, Tom learned every aspect of his business, from start-up and financing, to product development and procurement, to marketing, sales and order fulfillment. Through it all, Tom handled budgeting,  payables, receivables and collections, personnel hiring and training, and regulatory compliance (both domestic and international).

After over a decade in Red Hook, Tom became involved in local politics and was elected to the Dutchess County Legislature, in which he served his district for two years. While in the Legislature, Tom was appointed Vice Chairman of the Public Works & Capital Projects Committee,  dealing with important infrastructure and budgetary issues. Following his stint with the County, Tom moved on to the State level, where he spent almost two years serving as the Chief of Staff to the Majority Leader of the New York State Senate. During that time, he oversaw all policy development and legislative initiatives, managed the staff and budget, handled constituent services, acted as liaison to the Senate leadership and central staff and planned media strategy and events.

Since returning to the practice of law, Tom has brought a wide practical knowledge of the inner workings of business, government, law and politics to our firm. He also understands what it takes to get things done.

Jon Gautier

Jon first came to the Hudson Valley when he attended Vassar College in Poughkeepsie. After college, Jon returned to New York City, where he graduated first in his class from New York Law School as a member of the Law Review. Jon’s first legal job was with the Wall Street firm of Sullivan & Cromwell, where he litigated cases in the areas of securities, antitrust and environmental law for almost three years. Following his interest in securities law, Jon joined the US Securities & Exchange Commission as a staff enforcement attorney. While at the SEC, he handled numerous complex investigations and litigations, including fraudulent stock offerings, Ponzi schemes, and registration violations.

After almost eight years with the SEC, Jon went to another Wall Street firm, Cadwalader, Wickersham & Taft, to work on the administrative side of the legal business. In five years there, Jon was exposed to law firm management and marketing, and had the opportunity to hone his writing skills on long and complex RFPs as well as articles, web content and marketing materials. During this time, Jon also worked as an Adjunct Professor of Legal Writing at Fordham University Law School, where he taught classes on legal writing and research.

Jon subsequently returned to the Hudson Valley to help manage a family-owned winery in Red Hook for three years. While there, Jon learned all the aspects of running a small manufacturing and retail business, including sales, marketing, accounts, personnel, budgeting, and regulatory compliance.

An interest in local politics then led Jon to a two-year stint as the Deputy Clerk of the Dutchess County Legislature, where he learned the ins and outs of County politics as well as the management of a governmental office including budgeting and personnel. While at the Legislature, Jon was also able to use his legal, marketing and business writing skills by drafting legislation, press releases, and position papers.

Jon has returned to the practice of law having added valuable practical knowledge in business, government and politics to his already strong writing skills and extensive litigation experience.

Lisa Rosenthal

A graduate of Sarah Lawrence College and the Benjamin Cardozo School of Law, Lisa began her career as a litigator; she excelled at it, and she never looked back. Starting out with the Wall Street firm of Stroock & Stroock & Lavan, Lisa plunged into all manner of litigation: real estate, commercial, regulatory, securities, employment, and environmental. During this time, Lisa became a seasoned trial and courtroom attorney, trying her own cases, and handling numerous motions, appeals and oral arguments.

After almost seven years in private practice, Lisa left to join the US Securities and Exchange Commission where she added to her already broad experience with a specialty in securities law. While at the SEC, she investigated and prosecuted complex and technical securities cases. Lisa was promoted to management while at the SEC, becoming a Branch Chief overseeing five staff enforcement attorneys.

Lisa returned to private practice after seven years with the SEC, working at two small New York City firms where she continued to litigate complex commercial cases. In addition to working on securities law matters, she has also added to her repertoire by doing residential and commercial real estate closings, real estate disputes, commercial matters, and collections. For over ten years, Lisa also taught as an Adjunct Legal Writing Professor, first at her alma mater Cardozo Law School, and then at Fordham University Law School.

Lisa’s decades of legal work have created a wealth of knowledge and experience that is invaluable to our clients.

  • Real Estate
  • Litigation
  • Alternative Dispute Resolution
  • Wills, Trusts & Estates
  • Contracts & Business Law
  • Corporate Governance
  • Debtor & Creditor
  • Regulatory Matters
  • Securities Litigation & Arbitration