Mark P. Sullivan, Partner

Mark P. Sullivan’s practice focuses on defending complex civil cases in the areas of medical malpractice and general liability from inception through trial. After starting his career at the Legal Aid Society where he was a fully certified felony trial attorney, Mark served as principal law clerk to a judge for two years before beginning his career in civil litigation at Aaronson Rappaport over two decades ago. Mark then spent over ten years defending various hospitals and affiliated employees at all stages of litigation through trial while working for the largest public hospital system in the country where he also acted as legal adviser to various hospitals during medical staff hearings. After joining another firm where he continued to specialize in defending medical malpractice cases, Mark returned to ARFD as a partner in 2023.

In his years of practice, Mark has obtained numerous favorable results for clients at all stages of litigation through trial. Highlights of some of his successes include:

• Defense verdict on behalf of a Queens Hospital in a pediatric case claiming negligent failure to remove a foreign object from an infant’s nose leading to infection and permanent disfigurement.
• Defense verdict on behalf of a Queens Hospital and trauma surgeons in a case claiming negligent treatment of a stab wound resulting in multiple subsequent surgeries.
• Defense verdict on behalf of a Queens PICU in a case alleging negligent treatment of a trauma patient in the PICU resulting in multiple bedsores and permanent disfigurement.
• Defense verdict on behalf of a Brooklyn Hospital in a case claiming negligence during a gynecology exam leading to a fractured spine and the need for spinal fusion surgery.
• Directed verdict at the close of the evidence presentation at trial on behalf of a Brooklyn Hospital in a case alleging failure to diagnose infection leading to the death of a married father of five children.
• Summary judgment on behalf of a Brooklyn internist in a case alleging wrongful death of a 35 year old married father of three children.
• Summary judgment on behalf of a Brooklyn Hospital where the allegation was purported mismanagement of a 31 week premature infant’s congenital malformation leading to global delays requiring 24/7 care.
• Voluntary discontinuance on behalf of a Brooklyn cardiothoracic surgeon in a case alleging wrongful death of a married father of four children after undergoing complex cardiothoracic surgery.

Mark received an undergraduate degree from Fordham University and a Juris Doctor from Brooklyn Law School where he was an Edward Sparer Public Interest Law Fellow and a member of the Moot Court Honor Society. He is admitted to practice law in the State Courts of New York and New Jersey and to federal court within the Southern District of New York, the Eastern District of New York, and the District of New Jersey.

In addition to his defense work, since 2008, Mark has been an adjunct professor of law at Seton Hall University Law School where he has taught various litigation skills courses. He has also served as a faculty member of various National Institute of Trial Advocacy seminars in New York and New Jersey.