Tristan represents individuals and companies in complex business litigation. He has handled matters in state and federal courts as well as various administrative boards. Tristan regularly litigates contract disputes, claims of breach of fiduciary duty, non-solicitation and non-compete agreements, and civil claims under the RICO statute. He has also represented contractors and land owners in disputes involving real estate, and handled landlord/tenant disputes. Tristan has also defended attorneys against ethical charges brought by the Office of Bar Counsel, and often litigates matters dealing with the Massachusetts public records law, open meeting law, and conflict of interest law.

Tristan has an active criminal defense practice in which he represents defendants at trial and on appeal.  Tristan is a member of the CPCS Post Convictions and Appeals Unit and accepts criminal appeals on behalf of indigent defendants.  He has also argued pre-trial bail motions in the Superior Court and has successfully argued for the dismissal of charges at clerk-magistrate hearings where the defendants were accused of disturbing the peace, keeping a noisy house, and hosting gatherings where minors consumed alcohol.

After law school Tristan clerked for Judge Gustavo A. Gelpí of the United States District Court in Puerto Rico. He has extended family and many professional connections in Puerto Rico, and is well situated to assist parties bringing or defending suits in federal court in Puerto Rico.