Copyright 1995 Boston Herald Inc.
The Boston Herald
May 14, 1995 Sunday FIRST EDITION
SECTION: NEWS; Pg. 09
LENGTH: 1266 words
HEADLINE: Thread of evidence;May be only link needed to solve a crime
BYLINE: By TOM MASHBERG
BODY:
For the Atlanta child murderer, it was a few curly dog hairs. For the World Trade Center bombers, a sliver of seared debris. And for the kidnapper of 12-year-old Polly Klaas, it was a partial palm print that could never have been located just five years ago.
It is hard scientific evidence - the kind being used to put blood on the hands of O.J. Simpson and help retrace the steps of the Oklahoma terrorists - and in the last 15 years it has become as vital to gaining convictions as eyewitness accounts or signed confessions.
"Gone are the days when I'd arrive at a crime scene and only pick up whatever I could spot," said Dale Moreau, a special agent with the FBI Science Crime Labs in Washington for 20 years. "Nowadays, I'm far more interested in what I can't immediately see."
What Moreau can't see is often at first invisible. It might be buried under tons of rubble, or pressed into the mesh of a shag rug. It might even be encoded in the cells that make up a hair follicle, sweat stain or blood droplet.
The key, experts say, is to find it, analyze it and impress a jury with it, in the same way once limited almost exclusively to fingerprint matches or pointed fingers.
"You can try to blow up your evidence, or wash it away, or dispose of a victim's body, or just pray that nothing will ever be found," said David L. Brody, who runs the Boston Police Department Crime Lab Unit. "But we'll still find or reconstruct virtually anything to a microscopic degree."
It was just that kind of knees-and-elbows conscientiousness that launched the modern age of science-crime detection in 1980, with the arrest and conviction of Wayne Williams in the 22-month Atlanta child-murders case.
Even then, the public was skeptical that prosecutors could make a case against a man accused of killing at least 30 youngsters based on nearly invisible dog hairs and carpet fibers - items that most potential jurors would likely regard as indistinguishable.
But the case held, and within the next 15 years federal agents were using similar skills to rebuild both the truck and the explosive used on the World Trade Center; to connect O.J. Simpson to the scene of his wife's murder; and even now to sift the wreckage of an entire Oklahoma City federal building for every bit of metal or wiring left behind by the bomb that blew it up 25 days ago.
Hairs and Fibers
Back in 1979, newspapers around the world carried headlines about the continuing disappearances of boys in the Atlanta area. The victims did not know each other and were killed in differing ways. Police had one connection: green-orange carpet fibers found in the boys' hair or clothing.
Special Agent Hal Deadman of the FBI Lab was asked to to have a look. "Every company makes their own fibers, and so they are unique. These were pretty unusual, and I was able to track down the manufacturer" - which was a Massachusetts firm, Wellman Inc.
Ultimately, agents would have knocked on the door of everyone near Atlanta who had ever bought the firm's green-yellow carpeting. But word leaked out about the fibers, and the killer started dumping subsequent victims in Atlanta's Chattahoochee River in an effort to wash away evidence.
Police staking out the river crossings arrested Williams, and got a search warrant to comb his house for fibers and hairs. Hundreds were taken into evidence, and many matched hair or clothing from the victims. Williams had a poodle, and his curly hairs were on two of the bodies.
"Wayne Williams is still in jail, and hairs and fibers are part of our basic academy training," said agent Wayne Oakes, who runs the department. "Juries find it to be very impressive stuff."
Such threads of evidence were used to help convict famous multiple killers like Ted Bundy, who had one victim's hair on his lapels; Jeffrey MacDonald, who left incriminating pajama fibers on his slain daughter; and Richard Allen Davis, who left torn clothing from Polly Klaas near his parked car.
Hairs and fibers may play a smaller role than blood in the Simpson case, but prosecutors plan to allege that both Simpson and Ronald Goldman's hairs were on the same knit cap at the scene.
As Brody of Boston's crime lab said: "It all may depend on the difference between two hairs."
Explosives
With smoke and fear still thick in the air from the explosion minutes earlier, federal agents were already picking through the rubble of the Oklahoma City federal building for the bits and pieces of the bomb that destroyed it.
"Every bomb leaves a distinctive signature, like a giant footprint," said Andrew Armstrong, a forensic chemist in Texas and a former ATF agent who investigated the World Trade Center blast in 1993. "It's like reverse-engineering. You look at the component and recognize the bigger thing, like a mechanic saying, 'Hey, this is a part from a 1935 Dodge!"'
Investigators can also look at scorch marks and the degree of mangling to determine whether a piece of twisted metal was part of the bomb, the car used to carry it, or another car parked nearby.
In the case of a mail terrorist like Unabomber, "You can recog- nize the individuality of a designer, and even tell if he's left- or right-handed in the way he solders connections," Armstrong said.
In both the Trade Center and Oklahoma City cases, investigators found traces of ammonium nitrate near the epicenter of the blasts, helping them determine that the bombs were homemade concoctions rather than more sophisticated foreign devices.
More vital was finding vehicle parts with identification numbers imprinted on them. Those so-called VIN numbers led to the men who rented the cars that blew up.
"We're at the point now where we can trace residue of the actual substance that blew up to the actual homes or clothing of the bad guys," Armstrong explained. "They can't see it or wash it off, but we can sure find it on them. It's like giant bloodstains."
Blood Evidence
The bloodstains at issue are small but just as telling in the O.J. Simpson case, which has lifted acclaim for DNA evidence to heights once reserved for fingerprints. In the future, criminalists say, every human will be identifiable by his or her "genetic blueprint," and unlike the case with fingerprints, wearing gloves won't be enough to keep the crime scene clean.
"Imagine a nationwide FBI database of known criminals' DNA markers," said Capt. Det. Harold C. Prefontaine, commander of the Boston Police Department's Technical Services Division. "Then imagine finding some unexplained hair or blood at a scene, or capturing the semen from a rape victim or the saliva off a cigarette butt.
"You run that crime-scene evidence through the FBI computer and make a good connection," he said. "Now you have a suspect to start with. It's truly ideal."
DNA typing won big headlines in 1986, when British scientists first used it to solve a rape and murder. Last year, 5,000 such tests were used in criminal cases in the United States. There are high-profile successes, especially in rape cases, but also a notorious instance in which a rogue lab technician in Virginia, Fred Zain, falsified results against rape suspects.
But proponents note that a later DNA test was used to exonerate the innocent man and to convict the tamperer himself.
"DNA is the single biggest advancement in forensics in 100 years," said Paul Ferrara, the current director of criminal science in Virginia. "It's giving the Simpson lawyers fits, as you can see from the last week. I believe that jury now knows it was Mr. Simpson's blood there, and is wondering quite seriously how it got there."