William Castro graduated from Columbia College, Columbia University, and the University of Pennsylvania Law School. He is an experienced federal criminal trial and appellate defense attorney. Professor Castro represents clients at all stages of a federal criminal matter, including pre-indictment investigations, pre-trial and trial litigation, sentencing, appeals, and postconviction relief. In addition to being admitted to practice in New York, he is admitted to the United States Supreme Court, bars of six federal appellate courts and three federal district courts, including the federal district courts in Manhattan and Brooklyn, and is available to appear pro hac vice in other federal courts around the country.

Professor Castro was the 2022 recipient of the Miami Catholic Lawyers Guild “Lex Christi, Lex Amoris” award and presently serves as Secretary of the Guild. As an Adjunct Professor, he has taught Professional Responsibility at the St. Thomas University College of Law since the Spring 2024.