Casey Sherman's interest in his aunt's murder was aroused in 1988 when he saw the Tony Curtis movie "The Boston Strangler" and then heard his mother express doubt that the crime was committed by DeSalvo.
His book, "A Rose for Mary," is based on 15 years of studying transcripts, comparing autopsy reports, and interviewing 40 people, including the mystery man from New Hampshire, who is referred to in the book by the pseudonym Joseph Preston Moss.
In jail on unrelated charges, DeSalvo confessed to the strangling murders, although no physical evidence linked him to the crimes and he was never charged. He was murdered in prison.
Sherman does not suggest the mystery man from New Hampshire was involved in any other murders, and indeed Sherman makes a case that there may have been no Boston Strangler at all -- that the 11 victims may have been killed by five different murderers.
With the aid of WBZ-TV's investigative unit, Sherman located "Moss" in New Hampshire, telephoned and said he wanted to ask about the Strangler case, specifically about Mary Sullivan.
"Didn't they get the guy?" Moss reportedly said.
"No, not yet," Sherman answered and made a reference to the lie detector tests Moss had failed. According to the book, Moss replied: "Those things aren't scientific."
Sherman says he told Moss that some people were convinced Moss was the murderer and asked if he'd submit to a DNA test. Moss declined, says Sherman, and slammed down the telephone.
Last year, an acquaintance of Moss's in New Hampshire, working surreptitiously in alliance with Sherman, plucked strands of hair from a cap worn by Moss. Sherman says a DNA test found a partial match. (Mitochondrial DNA testing can exclude a suspect but not incriminate a killer.)
Last year, Sherman drove to New Hampshire to confront Moss.
"It was nerve-racking," said Sherman, who is 5-foot-2 but trained in martial arts. "I didn't know what to expect. I'd written letters to my wife and daughter, in case the worst happened, to let them know I loved them."
Sherman made an appointment for a golf lesson under a fake name and recalls the shock when Moss realized who he was.
"It was like the ghost of Christmas past haunting him."
The conversation lasted 45 minutes, said Sherman, and Moss lapsed into a stutter, a speech impediment he'd had as a boy.
"His hands were fidgety, and he was looking all around, eyes shifting, obviously not knowing whether I was going to attack him or call him my aunt's killer in front of 50 golfers.
"Through the conversation, he contradicted his story," Sherman says. "Finally I asked what he was doing the day my aunt was murdered. His reply was that he was watching a football game with his grandfather. When I asked what teams, he had no idea.
"What began as contentious turned to pleading by him. He tried to sympathize with the loss of my aunt, and I had to swallow my anger because I was tempted to grab him by the shirt, shake him as hard as I could and yell all the things I know my mother wishes she could say to Mary's killer.
"I wasn't intimidated at all because he was so pathetic, and when I turned to leave, he tried to shake my hand, but I slapped it away. I was not going to shake hands with my aunt's killer."
Sherman says he looked up the date of his aunt's death -- Jan. 4, 1964, a Saturday -- and found that no college or pro football was played or televised that day.
Sherman's book will draw national attention when he appears on network television talk shows later this month, but whether it will inspire prosecutors to reopen the investigation is unclear.
"Technically, the case is open because it's a homicide and no one's been charged in Mary Sullivan's death," said Ann E. Donlan, spokeswoman for Attorney General Thomas F. Reilly. "But . . . it's not an active investigation."
The publisher, Northeastern University Press, made an unusual decision to use a pseudonym to protect the privacy of the mystery man from New Hampshire but at the same time to provide information that could lead to his identification. (The Globe has determined his identity, but he did not return calls to his home yesterday.)
"This is something we thought hard about," said Sarah Rowley, an editor with Northeastern Press. "We stand strongly by Casey, but obviously the man has not been tried in court yet, so there's respect for privacy and for the law. We understand that any reporter worth her salt or his salt would be able to track the information, but a large purpose of the book is to refocus attention on the case, or the cases, and to get the interest back in uncovering what really happened."
An attorney representing the DeSalvos said the family would have no comment.
"Is the book out?" said Elaine Whitefield Sharp of Marblehead. "If you send me a copy, I'd be happy to confer with the family and see if they want to respond, but the DeSalvo family was not consulted and gave no permission for this. Mr. Sherman said he was going to share a copy of the manuscript with us, but he never came through with that." (Sherman says he never promised to send a manuscript.)
Sharp said DeSalvo had been absolved of responsibility in the murder of Sullivan by George Washington University law professor James Starrs, who led a forensic team that exhumed the bodies of DeSalvo and Sullivan.
In the book, Sherman never says flatly that Moss is guilty. "I say he's the prime suspect. I say he may have done it. Personally, do I think he's guilty? Yes. For publisher's reasons, they want to protect themselves. But all readers have to do is examine the facts and judge for themselves."
© Copyright 2003 Globe Newspaper Company.