Real Name: Mary Anne Sullivan
Nicknames: No known nicknames
Location: Boston, Massachusetts
Date: January 4, 1964
Details: On January 4, 1964, roommates found 19-year-old Mary Sullivan raped and strangled to death with a dark stocking. A "Happy New Year" card was placed at her feet. Authorities collected semen from her body, but in 1964, forensic evidence was not able to identify her killer. They soon connected her murder to the twelve other Boston, Massachusetts murders in the past two years, committed by the same man. They called him the "Boston Strangler" because each victim had been strangled in a similar fashion. Officially, she was the last victim of the killer.
Over many months, investigators had several strong suspects but no arrests were made. However, in early 1965, a twenty-nine-year-old inmate at a local mental hospital named Albert DeSalvo confessed to Mary's murder along with the others. Although he was never charged, he was named the killer. He was sent to prison for unrelated sexual charges until he was stabbed to death in 1973.
However, two families recently have made an unlikely alliance to challenge his guilt: the Sullivans and the DeSalvos. In the Fall of 1999, Casey Sherman took a renewed interest in the Sullivan case. Casey is the son of Diane Dodd, Mary's older sister. Diane and Casey never believed that Albert killed Mary, so they asked Boston investigators if any physical evidence was still available from the case. Unfortunately, none of the physical evidence was saved, so they decided that Mary's body needed to be exhumed to find any physical evidence left by her killer.
The Sullivans asked for help from George Washington University professor and forensic scientist James E. Starrs. He used a florescent light to find any traces of seminal fluid. Some fluid was found on Mary's pubic hairs, so they were removed for testing. He asked for help from forensic molecular biologist Dr. David Foran. He and his partners were able to successfully remove DNA samples from her body, which they isolated from Mary's DNA. The foreign DNA was compared to DNA from Albert's brother, Richard. The results showed that the foreign DNA did not match Richard or his relatives, so Albert could not have been her killer.
Casey has found several possible suspects that were not thoroughly investigated by police after Albert was arrested, but his aunt's killer is still unidentified.
Suspects: The original investigators had identified two possible suspects in the case, both of whom had access to the apartment. The suspects were Mary's ex-boyfriend and her roommate's boyfriend. One piece of evidence that connected the ex-boyfriend to the case was an ascot that was found cut up in the toilet. Mary bought the man ascots as presents. Her sister, Diane Dodd, believes that he was abusive and could have killed her.
An eyewitness saw a man matching the description of her roommate's boyfriend in their apartment around the time Mary was killed. On the day before the murder, the roommate had spent the entire day with him. Also, he apparently took their key to the apartment, as the key had gone missing that day. Finally, he failed a polygraph test, but once Albert confessed, investigations into the two men stopped. Her family believes that the person who killed her was someone she had known.
Extra Notes: This case first aired on the June 28, 2002 episode.
Results: Unresolved. On July 11, 2013, Boston police released information that they had discovered DNA evidence linking DeSalvo to the murder of Mary Sullivan. DNA found at the scene was a near certain match to DNA taken from a nephew of DeSalvo. A court ordered exhumation of the body in order to test the DNA correctly. After the exhumation, authorities announced that they now have an "unprecedented level of certainty" that he raped and strangled Mary. However, DeSalvo's connection to one murder does not confirm his culpability in the other murders.
- Mary Sullivan on Unsolved Archive
- New DNA Testing Ties Boston Strangler to 1964 Mary Sullivan Murder
- DNA confirms Albert DeSalvo’s link to ‘Boston Strangler’ killing of Mary Sullivan
- Mary Sullivan at Find a Grave