CAMBRIDGE, Mass. — A convicted rapist who died in 2001 has been identified as the killer of a 23-year-old Harvard University graduate student nearly 50 years ago, a Massachusetts prosecutor said Tuesday.
DNA evidence points to Michael Sumpter as the man who killed Jane Britton, who was sexually assaulted and bludgeoned to death in her Cambridge apartment in January 1969, Middlesex County District Attorney Marian Ryan said.
Britton's slaying is the third killing to which Sumpter has been linked since his death at age 54.
Investigators have said he is also responsible for the slayings of two other women in the Boston area in the 1970s. He died of cancer shortly after being paroled from a 15- to 20-year sentence for raping a woman in her Boston apartment in 1975, Ryan's office said.
Investigators gathered a DNA sample from a male relative of Sumpter to help close Britton's case, Ryan said. It's the oldest case her office has been able to solve, she told reporters.
"I am confident that the mystery of who killed Jane Britton has finally been solved and this case is officially closed," Ryan said in a statement.
Britton's body was found on her blood-stained mattress by her boyfriend who went to check on her when she didn't show up for a test that morning, prosecutors said. The night before her body was found, she had gone to dinner with classmates and went ice skating with her boyfriend in Cambridge.
Britton was studying anthropology at Harvard, and her father was at the time a vice president at Radcliffe College, a women's school in Cambridge that later merged with Harvard.
Britton's brother thanked officials for keeping active the investigation into the crime that "shattered Jane's promising young life" and his family.
"The DNA evidence match may be all we ever have as a conclusion. Learning to understand and forgive remains a challenge," the Rev. Boyd Britton, vicar at an Anglican church in Santa Barbara, California, said in a statement.
Sumpter was also linked by DNA in 2012 to the sexual assault and killing of 24-year-old Mary Lee McClain in her Beacon Hill apartment. Two years earlier, authorities said DNA suggested he was also responsible for the rape and slaying of 23-year-old Ellen Rutchick in the city's Back Bay neighborhood. DNA has also linked him to a rape in Boston in 1985, prosecutors said.
Prosecutors say they don't believe he knew any of his victims.
Relatives of Sumpter couldn't immediately be found through public records.