Very relevant to Zodiac case and ongoing DNA analysis. See bold text. https://www.bostonglobe.com/metro/2018/11/20/after-almost-years-prosecutors-blame-serial-rapist-for-unsolved-murder-harvard-student-jane-britton/RSPc7JJQcCcGjW3nVVc7lJ/story.html

For years, amateur investigators speculated about who might have killed Jane Britton, a popular Harvard University graduate student found bludgeoned to death in her Cambridge apartment in 1969.

People sent theories to police. They gossiped about the case on Internet forums. Many were convinced the killer had to be a neighbor, classmate, or someone else she knew at Harvard because no one heard Britton scream and her valuables were left untouched.

All the theories turned out to be wrong.

After conducting fresh DNA testing and analysis, Middlesex County investigators announced Tuesday they have at last identified the man they believe is Britton’s killer: a serial rapist and killer named Michael Sumpter, who died in 2001 and has since been linked to the murders of two other women he didn’t know.

In 2010, investigators connected Sumpter to the 1972 rape and slaying of Ellen Rutchick, 23, at her Beacon Street apartment in Boston. Two years later, authorities said DNA evidence showed he was responsible for the 1973 murder and sexual assault of Mary Lee McClain in her Beacon Hill apartment. In all three cases, investigators believe Sumpter did not know the women.

Sumpter, who died of cancer while on parole at the age of 54, was convicted of raping a stranger at her Boston apartment in 1975 and assaulting another woman he met at the MBTA’s Harvard Square Station, just blocks from Britton’s apartment, three years after Britton’s murder. After his death, Sumpter was also linked by a DNA match to a 1985 rape in Boston.

Investigators said previous DNA testing had generated a “soft hit” pointing to Sumpter, but it wasn’t conclusive. This time, investigators used newer technology to obtain a more detailed DNA profile from the swabs collected from Britton’s body, which matched Sumpter’s DNA profile in a law enforcement database.They were also able to track down a new DNA sample from Sumpter’s brother, which also pointed to Sumpter and ruled out his brother. The results excluded 99.92 percent of the male population, officials said.