DeSalvo was convicted of unrelated offenses and sentenced to life in prison, leading many to believe the Strangler was locked away for good.
But was DeSalvo really the killer? Authorities could find no definitive physical evidence linking him or anyone else to the murders. Some experts say that may be because they didn't have the right tools to look for it. In the past 36 years, the technology of criminal investigation has changed enormously.
"No police department had computers. Certainly that would have aided in the compilation and analysis of the comparison of evidentiary material," says Susan Kelly, author of The Boston Stranglers.
Kelly believes several different killers are responsible for the deaths.
And she is not alone. Robert Ressler, a criminologist and former profiler for the FBI, says the Boston Strangler killings don't fit the single-murderer theory.
But the study of criminal profiling was still in its infancy back in the early 1960s. "This was a classic case for the input of (a profiler)." says Ressler.
"The term serial killer hadn't entered the language," says Kelly. "The precise pathology behind serial killings hadn't yet been constructed as a general profile."
Ressler and Kelly both believe the tools used today to produce a psychological profile, if used in the original Boston Strangler investigation, would have directed authorities to look for more than one killer.
And one of the latest tools for identifying suspects was unfathomable in the early 1960s, says Kelly: "It was not possible to test for DNA from any kind of substance removed from a crime scene or from a crime victim 35 or 40 years ago."
James E. Starrs, professor of law and forensic sciences at George Washington University, and a team of experts are now using modern crime-scene technology to find answers to one of the Boston Strangler murders.
They have exhumed the body of the last victim, Mary Sullivan. "Back in 1964, they didn't have the familiarit we now have with respect to what we expect to find on - crime-scene bodies," says Starrs.
He hopes to find DNA samples that will help determine the killer.
But DNA testing is not the only new technology Starrs is implementing: "Today, unlike the days of 1964, we use ultraviolet light to test for seminal fluid and saliva," explains Starrs. "We have on-site X-ray machines. We have a great deal of additional knowledge with respect to physical anthropology and radiology."
Starrs says after almost 40 years, tissue from Sullivan's body was so well preserved it could undergo a series of toxicology screens to determine whether drugs or poisons were in her system at the time of her death.
New crime-scene technology has also created new procedures for handling the evidence. But sometimes old habits can get in the way when reinvestigating a decades-old crime. Says Starrs: "Today, we are much more careful about the probabilities and the hazards of contamination which, not having all of the very fine-tuned technology back in 1964, they didn't have to be concerned about."
Starrs plans to announce results from toxicology screens from the autopsy soon.
By Mike Wuebben. (c) MMI, Viacom Internet Services Inc., All Rights Reserved