DNA in old crimes might yield suspects

COLUMBIA - Investigators across South Carolina are hoping long-dried spatters of blood, stray hairs and discarded cigarette butts could be the clues that crack unsolved murders and rapes.

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In the world of forensic science, DNA - the unique genetic code found in all human tissue and bodily fluid - has virtually supplanted fingerprints as the best physical evidence in tough-to-crack cases.

Jurisdictions across South Carolina are digging through old cases in search of genetic evidence that can be evaluated by the South Carolina Law Enforcement Division's crime lab, in the hopes that suspects will finally surface.

The recently announced SLED cold-case initiative is a product of the growth of the lab's DNA profile database. In 1999, the state maintained just 1,800 DNA profiles of identified people from samples submitted by convicted sex offenders. After the state Legislature in 2000 required most violent offenders to submit genetic samples, the database has grown to about 26,000 known profiles over the past two years, according to Lt. Ira Jeffcoat, the scientist in charge of SLED's DNA analysis.

With a sizable database to compare samples against, it finally has become worthwhile for the agency to test saliva, semen, blood, hair, tissue or bone from a sexual assault or homicide in which no suspect has been identified, said SLED Chief Robert Stewart.

"It used to be when there were cases where there was no subject to compare the DNA to, we wouldn't accept them," Chief Stewart said. 'Now we're accepting them and analyzing them in hopes of getting a hit."

This month, SLED announced it had received a $450,000 grant from the U.S. Department of Justice to pay for lab employee overtime and equipment for cold-case DNA analysis. So far, the lab has received about 200 samples of unknown suspects from law enforcement agencies across the state, Lt. Jeffcoat said.

In Aiken County, sheriff's investigators will be sending the lab physical evidence from three unsolved homicides dating back to 1995, said Capt. Wallace Owens, the chief investigator. He declined to specify which cases would get another look, but said the county's entire backlog of at least 17 unsolved murders dating to 1993 would be combed over for physical evidence.

"Some will have DNA evidence, some won't," Capt. Owens said. "You'd be surprised with some of the things that come back with DNA."

Scientists can now isolate DNA from saliva left on a cigarette butt and prepare a genetic profile from a single strand of hair, capabilities unavailable just a few years ago. The unique profile is entered into a computer system as a code which is continually checked against known DNA codes.

South Carolina has used DNA before to crack old unsolved cases.

The growth of South Carolina's DNA database of known felons will allow the State Law Enforcement Division crime lab to test more DNA evidence from unsolved cases across the state. The lab has received 200 samples from unsolved rapes and homicides since the cold case initiative began.

Evidence recovered from Aiken teen Jessica Carpenter's slain body was compared with samples taken from dozens of potential suspects before authorities got a match from Georgia inmate Robert Atkins, who had been entered into that state's database just a week before the hit, police have said. The match was made two years after the 17-year-old's slaying in August 2000.

If DNA evidence taken from a crime scene is sufficient in size, it can be compared against the FBI's database of more than a million samples from across the country, Lt. Jeffcoat said. The FBI requires at least 13 clearly distinct segments from the genetic strand to show up on a DNA test before it will run the evidence through its database.

South Carolina law enforcement officials are hoping to soon have an even larger pool of samples for comparison. Legislation is pending that would require all convicted felons to submit DNA samples, a law that passed in Georgia two years ago and greatly expanded the state's crime-solving capabilities.

For now, investigators will rely on the 26,000 or so samples they have, and hope to come up with a match that can put a decade-old case to rest. It's happening these days with more and more frequency.

"That's been the trend around the country," Chief Stewart said.

Reach Stephen Gurr at (803) 648-1394.

--From the Thursday, July 17, 2003 printed edition of the Augusta Chronicle