DNA test now standard tool in crime detection
The evidence was more than two decades old, but to scientists it was as fresh as the day it was found.
Deborah Jeannette Capiola, of Robinson Township, Allegheny County, was murdered on her way to catch a school bus on March 17, 1977. It wasn't until December 2000 that state police in Washington County made an arrest in the case after advanced testing technology on DNA evidence led them to her killer.
Twenty-three years after her death, police used a sperm sample found on Capiola's jeans to link David Robert Kennedy, 48, of Cecil, to the slaying.
Although Kennedy had been a suspect from the beginning, investigators lacked crucial evidence. The sperm sample was not large enough to be tested until 2000 when technological advances in DNA testing gave police the genetic link they needed to arrest the aircraft mechanic.
State police Cpl. Beverly Ashton, of Troop B in Washington, said her unit would not have had the success it has had at solving cold cases without the advancements made in DNA testing. The unit was honored last fall by the Law Enforcement Agency Directors of Western Pennsylvania for clearing 10 cold case homicides in Allegheny, Fayette, Greene and Washington counties.
"It's been an integral part in a number of cases," Ashton said. "It's been massively helpful because it's definitive science."
Once reserved for only high-profile cases, DNA testing has become a standard tool in crime detection, said Westmoreland County District Attorney John Peck. He added that DNA samples are taken in all sexual assault cases if there is fluid and tissue found.
"It's become very customary, rather usual, to use it if we can find DNA, " Peck said. "It's not discoverable in every case."
Christine A. Tomsey, a 31-year veteran of the state police crime lab in Greensburg, said that in recent years, DNA testing has been used to solve many low-profile criminal cases such as minor assault, harassment, stalking, and even breaking and entering cases.
"It's used in just about everything now. The technology is that in only two weeks we can have results in 16 genetic areas whereas a few years ago it could take up to four months to generate results in six genetic areas,” said Tomsey, who is in charge of the state police lab.
Peck said detectives investigating a Lower Burrell burglary found blood samples from the alleged burglar who had cut himself while breaking into a building. State police investigators later took a DNA sample from a crime scene in Hempfield Township and ran the samples through a national DNA database that the FBI maintains.
As a result, Timothy Woodward, of Hempfield Township, was charged with a series of burglaries. Confronted with the DNA evidence, Woodward admitted to investigators to committing several other burglaries, according to court records.
A person's genetic makeup is unique. No two people in the world share the same DNA except twins.
Twin brothers from Washington County caused some confusion for homicide investigators in separate killings.
Brian Calzacorto, 39, formerly of Donora, is serving a life sentence in a Florida prison for the 1990 rape and murder of a woman who lived in the same apartment complex in Clearwater, Fla. In addition to being raped, the victim was stabbed 16 times. Investigators found semen on the woman's body.
Calzacorto didn't become a suspect until four years later when detectives began investigating the backgrounds of every tenant who lived in the complex at the time of the slaying. He refused to give a DNA sample.
Police then learned that he had been the prime suspect in the 1986 murder of his father, Donora Police Lt. Alfred Calzacorto, although he never was charged with the killing.
The investigation was complicated by the fact that Calzacorto's twin brother, Alfred, also lived in Florida and would have the same DNA. After detectives learned Alfred was working 20 miles away in Tampa when the killing occurred, they began building a case against Brian.
Investigators rooted through Brian Calzacorto's trash and found cigarette butts and parts from an electric razor. Using saliva from the cigarettes and whiskers from the razor, they quickly linked his DNA to the semen sample found at the crime scene. He was convicted last year in Clearwater.
"While the technology has advanced by leaps and bound, it's still not 'Star Trek,'" Ashton said. "But I must say that when we find DNA evidence, we love it, and the advances made in the technology -- practically every day -- continue to amaze me."
Twelve years ago, James Swoyer, 23, of Jeannette, was killed at an adult bookstore along Route 22 in Murrysville. Swoyer was working at the store to earn money for college.
Within the past six months, detectives have turned to DNA analysis to try to break the case. Peck said a sample taken from a shoe at the murder scene was re-analyzed but the results were inconclusive.
Former county detective Tom Horan, now chief of security at the University of Pittsburgh at Greensburg, said a person appeared at the crime scene with a red spot on his shoe. He told investigators it was ketchup but allowed Horan to take a swab of the material.
The next day, Horan personally drove the sample to a Maryland-based lab that does DNA testing. Scientists warned Horan that the analysis would be a one-shot deal because the test likely would destroy the sample. Ultimately, the test was done but did not produce a suspect.
Last year, Horan learned that DNA testing would allow the blood on the sample to be regrown for another test that also was inconclusive.
"Even with advanced techniques, it couldn't help," Peck said. "We made the effort."
"If we were smart in 1992, we would have waited for technology to improve," Horan added.
Ashton said it's the advancements in technology -- and patience -- that enable investigators to solve long-dormant cases that might never have been solved.
In Fayette County, Ashton's unit used 22-year-old DNA evidence collected from the body of Linda Mae Covach, a Uniontown waitress, to charge James "Silky" Sullivan, 56, of Grindstone, with murder in 2001. Sullivan was already serving a 10-to-20 year sentence for the 1987 murder of Charles Wheeling, of Uniontown.
Ashton said Sullivan had been a suspect in Covach's death. A semen sample swabbed from Covach's body was matched against blood taken from Sullivan, who later was found guilty of the murder.
"Both of those cases are 20 years old," she continued. "It's remarkable what it can do and the advances in the technology even since the early 1990s when I came to the unit are remarkable. You used to need a blood sample the size of a quarter ... now you can take a small sample of sweat left in a ball cap or sweat on a sleeve or shirt collar to link a suspect."
But it's not always that easy.
Peck said during the investigation into the murder of an Armstrong County drug dealer, Larry Dunmire, in 2001, detectives hoped one of the killers' DNA would be on the victim because he was wearing a sweatshirt on a summer's day. Although DNA evidence did not solve the case in which Dunmire was stabbed 30 times and shot at least a dozen, police eventually arrested three men and three women who were convicted in connection with the crime.
"We hoped to find DNA on the cuffs," Peck said. "We had hoped to link the sweatshirt from Dunmire to one of the defendants."
"It's actually not the sweat we're able to find. We're looking for samples of cellular material … skin left from rubbing on the collar or sweatshirt sleeve, for example," Tomsey said.
DNA testing also has been used to identify human remains from homicides that have gone unreported.
In the late 1990s, detectives used DNA analysis to identify the remains of a newborn found buried in the basement of a Scottdale home.
Mendum Paul Corvin pleaded guilty to killing a child born to his daughter, whom he had impregnated in 1970. He also pleaded guilty to killing a previous child two years earlier when he lived in Florida.
Investigators, using the remaining brittle bones of the infant, linked Corvin to the births. Corvin died in prison in 2000.
When detectives dug up a Penn Township basement in 1999, they found the body of the former owner, Willis Casteel, who had been killed by his wife and stepdaughter in 1983. Investigators used a DNA sample taken from a shin bone and matched it with a blood sample taken from the victim's sister to confirm the identity.
Casteel's wife, Patricia Sloan, was convicted of first-degree murder and is serving life in prison. Her daughter, Bonnie Neely, pleaded guilty to third-degree murder and is serving a 20-year sentence.
DNA also has been used to clear suspects.
Nicholas Yarris, of Delaware County, spent 21 years on death row for the murder, rape, robbery and abduction of a Delaware County woman.
He was released from the State Correctional Institution at Greene County last fall after DNA tests of semen found on the victim's underwear and skin beneath her fingernails indicated Yarris could not have been her killer.
Meanwhile, Charles Godschalk, of King of Prussia, received $1.6 million last week from Montgomery County after spending 15 years in prison for two rapes. He was cleared of the crimes last year after DNA tests proved he could not have committed them.
In Westmoreland County, Peck said he had one case in which a DNA sample taken from the fetus of a rape victim did not match the alleged assailant.
The state House last week passed seven bills as part of a wide-ranging DNA package that would enhance criminal investigations.
The bills increase the statute of limitations on certain crimes in which DNA can be used and call for mandatory samples to be taken from any suspect arrested for a crime as well as persons already convicted and sentenced to life in prison or death. The legislation also includes a measure that would allow police to obtain a court order to get a DNA sample from a suspect to exonerate him in an investigation. Another bill would allow the families of missing persons to give police a personal item belonging to the missing person for DNA analysis.
DNA analysis also is being used in unlikely investigations.
The Pennsylvania Game Commission used DNA testing to charge a Pittsburgh man with illegally killing a black bear in 2000. Michael Autry was found guilty of killing the bear after commission agents used a DNA sample of hair and blood from the remains to link it with meat found at Autry's home.
Commission spokesman Jerry Feaser said wildlife officers are using DNA more in poaching cases, mostly in the illegal hunting of bear and deer.
"We used it several times in the past. We'll use it when it's relevant," Feaser added.
What is DNA?Deoxyribonucleic Acid -- DNA for short -- is material that governs inheritance of eye color, hair color, bone density and many other traits. It's a long, narrow stringlike object that consists of strands of molecular tissue in the shape of a twisted ladder resembling a spiral staircase.
Known as a double helix, this ladder is composed of sugar and phosphate molecules and held together by hydrogen.
Every part of the body is made up of cells that contain DNA, which is the genetic code or roadmap, so to speak, that makes individual traits unique. The DNA code is passed through the sperm and egg to the offspring.