19-year-old indicted in Cape Cod boat crash that killed 17-year-old Sadie Mauro

Cape & Islands District Attorney Robert Galibois announced that on Friday September 29, 2023, a Barnstable County Grand Jury indicted David K. Sullivan, 19, of Medfield, for his role in the July 21, 2023, death of a 17- year-old female victim.

David Sullivan was indicted on the charges of Death of a person caused by operating vessel/boat under the influence of intoxicating liquor, possess false RMV documents, minor in possession of alcohol, operation of a vessel while under the influence of intoxication liquor causing serious bodily injury (x2), and reckless or negligent operation of a vessel causing death.

At approximately 9:00 p.m. on July 21, 2023, law enforcement responded to a boat crash reported in Sesuit Harbor in Dennis. Upon arrival and further investigation, it was determined that the boat crash resulted in the fatality of a 17-year-old Sadie Mauro as well as causing serious bodily injury to two other individuals that were on the boat.

Sullivan is due in the Barnstable Superior Court on October 10, 2023, for an arraignment.

The charges stem from an investigation conducted by several law enforcement agencies including Dennis Police Department, Massachusetts State Police assigned to the Cape & Islands District Attorney’s Office, Massachusetts Environmental Police, State Police Marine Unit, Massachusetts State Police Dive Team, and the Barnstable County Regional Dive Team.

The Cape & Islands District Attorney’s Office added no additional details on the charges pending against Sullivan.

Mauro was a senior at Dover-Sherborn High School according to school officials. “Sadie’s smile could light up a room, she had a heart of gold and the sweetest spirit. She had such a strong sense of self and had a love for adventure and anything outdoors. A hardworking student and great athlete, Sadie was genuine and effortlessly kind.”

Sadie had participated in two state championships in lacrosse and was headed to play the sport in college.

Mauro was recovered, deceased, from the water by the USCG at approximately 11:30 p.m.

Six people, including Mauro, were on the boat. The recovery of Mauro from the water was made by the regional dive team with assistance from Dennis Fire-Rescue; and at least one other boat passenger, a teenage male, was transported to Cape Cod Hospital with a head laceration.