Gregory Grizopoulos is a founding partner of Grizopoulos & Portz, P.C. He aggressively represents individuals who are arrested and charged with crimes and also represents those who are injured due to the negligence of others.

In August 2002, Gregory was appointed Assistant District Attorney by the Honorable Denis Dillon, District Attorney of Nassau County. He also received a special appointment to be Nassau County's Stop-DWI Special Prosecutor and was assigned the responsibility of prosecuting serious, high-profile, media sensitive Driving While Intoxicated (DWI) and related vehicular cases. He received training from police officers and national training in the areas of Alcohol Breath Testing and Highway Safety, Standarized Field Sobriety Tests (SFSTs) and Accident Reconstruction with the New York City Police Department's Accident Investigation Unit. He has also lectured at the Nassau County Police Academy about how to cross examine a police witness.

In addition to handling major felony cases, Gregory was assigned to the elite Vehicular Crimes Unit under D.A. Kathleen Rice where he handled felony DWI offenses involving serious injury.

Prior to joining the District Attorney's Office, Gregory worked as a law clerk at the prestigious criminal defense firm of Eoannou & Lana in the City of Buffalo, New York. There he assisted in both federal and state defense cases including the successful defense of country music stars Tim McGraw and Kenny Chesney.

In 2006, Gregory entered private practice specializing in the areas of personal injury, criminal defense and DWI-Vehicular crimes defense. Since that time Gregory has developed a reputation for excellence as a trial attorney and skilled advocate.

Gregory has been quoted by the media in his representation of clients in high profile cases including Fox 5 News, News 12 Long Island, Newsday, the New York Post and the New York Daily News. Gregory is a member in good standing of the Nassau County Bar Association, Former District Attorneys Association and the Nassau County Criminal Courts Bar Association. He is admitted to practice law in the State of New York and the United States District Courts of the Eastern and Southern Districts.