Using DNA testing, scientists can analyze bodily fluids, tissue, or bone and develop a genetic fingerprint that narrows a person’s identity to one in many, many millions. The technology, developed in the 1980s, was made famous in the O.J. Simpson double-murder trial and has become common practice in courts across the nation.
Varlaro and Don Hayes, the director of the lab, located a semen stain on an old blanket found near one of the victims. But when they tested it for DNA, the sample had degraded to the point of being useless, Varlaro said.
“We are on a quest for semen,” he said. “We do have reason to believe these were crimes of a sexual nature.”
Investigators say they have to develop DNA evidence from at least two of the killings to prove or disprove that DeSalvo was a serial killer. If he is exonerated, they acknowledge, it raises the chilling possibility that one or possibly many more killers got away with murder in the frenzy of the original investigation.
One pitfall to the current effort: Murray and his partner, Lieutenant Stephen Murphy, have both been promoted out of what had been the Cold Case Squad, reassigned so that they are no longer directing the Strangler case.
As the other investigators regroup, Murray says it’s now up to the department higher-ups to determine the weight they will give the case.
“You approach it with an open mind,” he said. “You don’t come in with a preconceived notion that DeSalvo was the killer or not the killer.”