Guillermo focuses his practice on government affairs and complex business litigation. He advocates for clients across multiple industries, including telecommunications, technology, healthcare, education, energy, advertising, and fintech. Guillermo chairs McCarter’s Government Affairs practice, and leads the firm’s Cannabis Group.
As a registered Government Affairs Agent in New Jersey, Guillermo helps clients achieve their governmental, media, and business development objectives. As a former federal law clerk, Guillermo also provides local counsel expertise to clients involved in Hatch-Waxman and other complex litigation in the United States District Court of New Jersey.
Most recently, Guillermo served as Associate Counsel to Governor Philip D. Murphy, where he gained in-depth regulatory experience. In Governor Murphy’s front office, Guillermo handled legislative initiatives, overseeing a portfolio of departments and agencies that included Treasury, Banking & Insurance, Transportation, Economic Development, Environmental Protection, Motor Vehicle, and the Board of Public Utilities. Guillermo also handled appointments in Counsel’s Office and oversaw the Governor’s vetting process for judicial and prosecutorial candidates across the State.
Active in state and national politics, Guillermo was involved in the Joe Biden for President campaign. He serves on the national campaign team as a Lawyers for Biden Finance Council National Co-Chair, and is also the Co-Chair of Jersey for Joe and Founder of Jersey Lawyers for Joe.
Previously, Guillermo served as Corporate Counsel at Greenskies Renewable Energy, the largest commercial and industrial solar energy developer in the United States.
After law school, Guillermo served as a law clerk to the Honorable Esther Salas, United States District Judge, District of New Jersey.
During law school, Guillermo worked in the Intergovernmental Affairs Group of Governor Chris Christie, as the Governor’s Executive Fellow from Rutgers University’s Eagleton Institute of Politics.
In the community, Guillermo serves and has served as Trustee of the Hispanic Bar Association of New Jersey, Deputy Regional President of the Hispanic National Bar Association, Board Member of the New Jersey Legal & Education Empowerment Project, Statewide Hispanic Chamber of Commerce, Cuban American Alliance for Leadership & Education, Waterfront Project, Cuba Study Group, and Full Court Peace.