Scientist Says DNA Matches Suspect's

Evidence found at the scene of a rape and double slaying near Reston matches the DNA of Alfredo R. Prieto, who later moved to California and raped and killed a 15-year-old girl, a forensic biologist told a Fairfax County jury yesterday.

The DNA testimony was the linchpin, and the conclusion, of the state's case against Prieto, 41, for whom prosecutors are seeking the death penalty. Biologist Carol Palmer, from the state crime lab in Fairfax, said the chances that someone else left the DNA was one in 6.5 billion, roughly the world's population.

Prieto, who is on death row in California, is accused of killing Rachael A. Raver and Warren H. Fulton III, both 22, in a partly wooded lot on Hunter Mill Road early on Dec. 4, 1988. Each was shot once in the back, and Raver was raped.

There were no witnesses, no indication of how Prieto might have met Raver and Fulton, and no statements from Prieto. Further complicating the case for prosecutors, one of the few items of physical evidence found at the crime scene were two head hairs found on Raver's body. A hair examiner determined the hairs were of "Negroid" origin, which is not how hairs from Latino people such as Prieto typically are classified.

After DNA from semen linked Prieto to the case in 2005 and Prieto was extradited from California in 2006, Fairfax police in February took 25 head hairs from Prieto for new testing. It was classified "Caucasian-Mongoloid," not "Negroid," a hair examiner testified.

The jury also learned that all of the original hair evidence from 1988, including some found on Raver's chest and on her sweater, has vanished. A homicide detective testified yesterday that the crime lab returned the hairs to police in 1990, and they haven't been seen since.

In February, Prieto's defense attorneys asked Fairfax Circuit Court Judge Dennis J. Smith to dismiss the case or eliminate the death penalty because of the missing hairs. Smith declined, saying the hairs were not clearly exculpatory, or evidence of the defendant's innocence, and that there was no indication that the police purposely destroyed the evidence.

Raver, who had just graduated from George Washington University, and Fulton, a senior baseball star at GWU, were dating and were out with friends the night of Dec. 3, 1988. Witnesses testified that they left a D.C. sports bar around midnight and were not seen again. Raver lived in Alexandria; Fulton lived in Vienna.

Their bodies were found the morning of Dec. 6, not far from an exit for the Dulles Toll Road. A former co-worker of Prieto's, Marcos Tulio Sanchez, testified yesterday that he and Prieto worked as landscapers at Dulles International Airport in 1987 and 1988 and that Prieto sometimes mowed the toll road median out to Route 28. The testimony provided a previously unknown link between Prieto and the area of the killings.

Prieto's then-16-year-old girlfriend has also placed him in Northern Virginia at the time. She testified last week that Prieto lived in Arlington with her, his infant son and his father.

Prieto apparently moved back to California, where the rest of his family lived, in 1990. He was arrested in September 1990 for rape and murder, convicted and sentenced to death. While in prison, his DNA was taken and entered into a national data bank, connecting him to the Fulton-Raver case in 2005.

The jury was not told about the data bank, only that homicide detective Bob Murphy went to California in 2005 and took a swab of saliva from Prieto's cheek to get a DNA sample.

In September 2005, Murphy returned to Virginia with swabs from Prieto. Forensic biologist Palmer said she would expect to see a match between the DNA from semen found at the crime scene and the two sets of swabs "only once in 6.5 billion individuals, which means once in the entire world."

But one of Palmer's former colleagues, Myron T. Scholberg, said the head hairs he examined from Raver's body in 1988 were "Negroid." The hairs were not tested again to determine whether more than one person might have been involved, Murphy said. And when Prieto's hairs were tested this year, they were not classified as "Negroid," hair examiner Charles Linch said.

Closing arguments in this phase of the case could occur today.