FOUNDER & MANAGING PARTNER

Mark D. Sullivan Sr., Founder and Managing Partner, has focused his practice on criminal defense for more than thirty years. Since joining Sullivan & Sullivan LLP in 1999, he has handled all of the firm’s criminal defense work, with a concentration on operating under the influence of alcohol and drugs, domestic violence, and drug offenses. He represents both professionals and private citizens charged with misdemeanors and felonies, and has a particular focus on defending high school and college students in the region. Mark is deeply aware of the long-term consequences a criminal conviction can have on a client’s life and career.

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From 1987 to 1999, Mark ran his own practice representing criminal defendants charged with offenses ranging from first-degree murder to misdemeanors. He defended thousands of clients and tried hundreds of jury and jury-waived cases in the District and Superior Courts.

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Mark began his career in 1982 as an Assistant District Attorney in Suffolk County, where he tried hundreds of cases in both the District and Superior Courts. In 1985, he became head of the jury session at the Boston Municipal Court and concluded his service in 1987 prosecuting felony trials in Superior Court. For four years, he also served as a member of the homicide response team.

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A proud graduate of the University of Notre Dame, Mark earned his J.D. cum laude from Suffolk University Law School, where he wrote for the Law Review.

Phone: (781) 263-9400