One of the nation’s most notorious mysteries is on the brink of being solved, state and local officials said Thursday, as they revealed DNA evidence directly linking Albert DeSalvo to the last of the 11 murders committed by the Boston Strangler during a reign of terror that stretched across the region from 1962 to 1964.
Investigators and gravediggers plan to visit a Peabody cemetery on Friday afternoon to exhume DeSalvo’s remains. The intent is to retrieve a DNA sample that officials said should confirm DeSalvo raped and killed Mary Sullivan, a 19-year-old woman whose body was found in her Beacon Hill apartment in January 1964, thus putting to rest doubts over DeSalvo’s guilt that have festered across half a century.
At their extraordinary press conference Thursday, state and Boston law enforcement officials methodically briefed the public on an investigation that has largely been carried out in the secrecy of crime labs and musty evidence vaults. It began with the discovery of old evidence — strips of a blanket and slides holding seminal fluid — and reached something of a pinnacle this past January when an undercover police officer grabbed a water bottle that had been discarded by DeSalvo’s nephew and that held the DeSalvo family DNA.
That DNA provided a link to the samples left at the Sullivan crime scene.
“We may have just solved one of the nation’s most notorious serial killings,” Attorney General Martha Coakley said.
Sullivan’s nephew, Casey Sherman, who once expressed serious doubts that DeSalvo killed his aunt and accused officials of stonewalling his family, fought back tears as he expressed gratitude for their persistence.
“I’ve lived with Mary’s memory every day, my whole life, and I didn’t know, nor did my mother know, that other people were living with her memory as well,” he said. “It’s amazing to me today to understand that people really did care what happened to my aunt. . . . It’s taken 49 years for police to legitimately say they got their man.”
The water bottle used by DeSalvo’s nephew was recovered at a construction site. An attorney for DeSalvo’s relatives said they were furious that a DNA sample was taken without their knowledge and that they would have provided one if they had been asked. But the Suffolk district attorney’s office said that the family had not been cooperative in the past.
The Boston Strangler killed 11 women between 1962 and early 1964, a crime spree that stretched from Boston and Cambridge to Lawrence, Lynn, and Salem. The women were between 19 and 75 years old. Most of them were raped and strangled with their stockings or cords.
The city and its suburbs were in a panic as people rushed to buy guns and guard dogs.
“It was a crisis situation,” said former senator Edward Brooke, who was then the state’s attorney general. “The public was crying for some relief.”
They got it 1967 when it was revealed that DeSalvo, while being held on a series of unrelated rape charges, had confessed to killing 13 women. But his confession was ruled inadmissible in court, and he was never charged in the Boston Strangler cases. Instead, the handyman was sentenced to life in prison for the unrelated rape charges. An inmate stabbed DeSalvo to death in November 1973, when he was 42 years old.
On Friday, Boston detectives from the homicide unit’s cold case squad, the prosecutor in charge of the case, and assistant attorney generals from Coakley’s office will attend the exhumation of DeSalvo’s body. The remains will be taken to the medical examiner’s office on Albany Street, where a DNA sample should be retrieved by the end of the day. The results could come back as early as next week, officials said.
Suffolk District Attorney Daniel F. Conley said the results will answer questions only about the Sullivan case. But officials are hoping that DNA can help solve 10 other cases, even though there is no known biological evidence from those murders that can be tested.
Many of DeSalvo’s family members have maintained his innocence, in part because his confession contained inconsistent details about the crimes.
In 2000, Sherman stood alongside one of DeSalvo’s nephews at a press conference and demanded that their private team of forensic experts be allowed to test evidence from Sullivan’s killing. At the time, Sherman said authorities had knowingly left the real killers on the street.
Both families had the bodies of DeSalvo and Sullivan exhumed to obtain DNA samples. In 2001, a group of scientists working with both families said test results showed that while DeSalvo could not be ruled out as a suspect, they suggested strongly he did not rape and murder Sullivan.
On Thursday, Conley said he could not speak to those test results. “We weren’t confident in any event,” he said. “Those were not done by law enforcement.”
Conley said the results that law enforcement has obtained from two private laboratories show a 99.9 percent likelihood it was DeSalvo’s DNA at the crime scene. Evidence was taken from semen found on strips of a blanket discovered at the scene and from Sullivan’s body.
Analysts at both laboratories, which were working separately, obtained a DNA profile of the same unknown male. That profile was a familial match to the DNA taken from the water bottle discarded by DeSalvo’s nephew.
Elaine Whitfield Sharp, a lawyer representing DeSalvo’s family, said his relatives have misgivings about the new evidence.
“It’s very strong evidence; there’s no doubt about that,” she said. “But I think it’s important that from this evidence you can’t yet 100 percent infer that he killed Mary. Just because you find DNA that matched somebody on their body doesn’t mean they murdered them.”
Sharp said DeSalvo’s confession helps buttress the family’s contention that he did not commit the crimes.
“He made so many mistakes in his confessions that his confessions actually exonerate him, rather than indict him,” she said.
But F. Lee Bailey, who represented DeSalvo when he confessed to the Boston Strangler murders, said his client knew too many details that had not been revealed in the press.
“I believe that the detectives who determined that he was the man . . . were correct when they said close the file, this is the guy,” Bailey said.
For Brooke, the former attorney general, who is now 93, knowledge that there could finally be hard evidence connecting DeSalvo to at least one of the crimes is a huge relief.
“This is something that has been hanging over us for a long, long time,” he said. “If that’s all behind us and it’s over, thank God. It’s done. Let us pray.”Eric Moskowitz of the Globe staff contributed to this report. Maria Cramer can be reached at email@example.com.
Follow her on Twitter @GlobeMCramer.