Medfield teen indicted in boat crash that killed Sadie Mauro, 17

Mauro was a rising senior and a lacrosse player at Dover-Sherborn High School.

Sadie Mauro. Handout

David K. Sullivan, 19, has been indicted in connection to the July death of 17-year-old Sadie Mauro of Sherborn, Cape & Islands District Attorney David Galibois announced Tuesday.

On July 21, a boat carrying six passengers crashed into a jetty in Sesuit Harbor in Dennis, killing Mauro and injuring another passenger.

A grand jury indicted Sullivan, of Medfield, on charges of death of a person caused by operating vessel/boat under the influence of intoxicating liquor, possession of false RMV documents, minor in possession of alcohol, operation of a vessel while under the influence of intoxication liquor causing serious bodily injury (two counts), and reckless or negligent operation of a vessel causing death.


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

Sullivan is due for arraignment in Barnstable Superior Court on Oct. 10. 

In his announcement, Galibois stressed that all defendants in criminal matters are presumed innocent, and he expressed his condolences to Mauro’s family. He added that he would make no further comment on the charges against Sullivan at this time, “due to the nature of this matter.”

Mauro was a rising senior and a lacrosse player at Dover-Sherborn High School. In a letter to parents, Dover-Sherborn principal John Smith remembered her as “a hardworking student and great athlete … genuine and effortlessly kind.”


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