DNA Deluge Puts Lab to Test

Ventura County forensic scientist Jill Nguyen doesn’t look like a crime-solving sleuth as she sits behind a sterile counter in a white lab coat and handles a test tube containing a DNA sample. But don’t be mistaken.

Nguyen is part of an elite team of scientists at the county crime laboratory that has played a vital role this year in helping to crack unsolved homicide and rape cases.

Their expertise is in such demand by police and prosecutors that lab supervisors are now refusing some requests for genetic analysis because they are so overwhelmed and understaffed.”The demand outpaces the resources by such a phenomenal amount that every year that goes by we get pickier,” said Cmdr. Brent Morris of the Ventura County Sheriff’s Department, which runs the lab.

Thirty scientists annually process about 8,000 pieces of evidence in fields that include toxicology, firearms and fingerprint analysis. But the fastest-growing section is forensic biology, where scientists examine blood, semen and other bodily fluids for deoxyribonucleic acid, or DNA.

Six DNA analysts handle an average of 10 new cases each month while trying to make a dent in a backlog of about 270 cases, each of which could involve testing several samples. As a result, waits of six to eight weeks are common, although a test can be completed in about a week.

“We do the best we can,” Morris said. “But needless to say, we fall further and further behind.”

The situation is not unique. Nationwide, crime labs are deluged with requests for DNA analysis. The National Institute of Justice estimates that the current backlog of rape and homicide cases is about 350,000.

In California, a recent survey of lab directors revealed a backlog problem in five areas of forensic testing, with DNA representing the greatest challenge. Lab directors reported that it would require 326 additional staff members at an estimated cost of $26 million to meet the demands for DNA, toxicology and other testing.

The problem could soon be exacerbated by the state’s budget woes. A three-year, $50-million state grant to pay for DNA tests in older rape cases is set to expire next year. The money from the “cold-hit program,” which covers the costs of examining genetic material and entering offender profiles into a state database, has paid for two of the six analysts at the Ventura County lab.

Morris said the Sheriff’s Department will have to absorb the cost of those positions at a time when money is tight. He estimates that three more analysts are needed to keep pace with demand, yet a $400,000 funding request was recently turned down by the county.

Lab manager Renee Artman said her staff was working overtime to keep on top of the high-priority cases. “I wish we could analyze in a timely manner,” she said, “but right now we can’t.”

It is a frustration shared by prosecutors. Chief Deputy Dist. Atty. Michael Frawley, who supervises the major-crimes division, said his office was mindful of the staffing problems but had an obligation to seek DNA tests in homicide and sexual assault cases.

“There is so much at stake,” he said. “Even if we have other evidence, we are going to ask for DNA testing and if we didn’t we’d be taken to task for it.”

The DNA demand is understandable. In the last 16 years, since British authorities made the first arrest based on so-called “genetic fingerprinting,” the technology has become a powerful tool for catching the guilty and clearing the innocent.

Forensic scientists can now identify a suspect based on a speck of blood at a crime scene. They can extract genetic material from semen taken from a rape victim a decade ago and enter the profile into a state or federal database of convicted sex offenders in hopes of finding a match. They also can extract DNA from saliva on a cigarette butt or sweat soaked into a shirt, as was recently done in a Ventura homicide investigation.

Police officers investigating the shooting of a woman parked near a city golf course last year interviewed witnesses who reported seeing a man in a white T-shirt fleeing the scene. They found the gun used to kill Irene Mata, 22, in bushes and found a blood-spattered T-shirt on the golf course.

Forensic scientists determined it was Mata’s blood and developed a genetic profile of the killer by extracting sweat from the same garment.

At the same time, detectives narrowed a list of probable suspects based on interviews with Mata’s friends and eventually provided the lab with a sample of suspect Elmer Zepeda’s blood, taken from evidence in an unrelated case. It was a match.

Zepeda, 26, died from a self-inflicted gunshot wound in July before the lab completed the tests. Senior Deputy Dist. Atty. Richard Simon said investigators are not certain whether Zepeda knew he was a suspect or whether his death was a suicide or accidental. But they are confident he was the killer.

“There is no doubt, based on the DNA results,” Simon said. “The lab did a great job.”

DNA proved valuable in the Mata case for another reason: It exonerated an earlier suspect.

Harold Marshall, 32, was arrested and charged with murder after police learned he had been driving the car in which Mata was shot. Prosecutors dismissed the charge after the lab determined his DNA did not match the crime-scene evidence.

“That was one of those examples where it cleared an innocent man,” Frawley said. “And most of the time, it seals the fate of a guilty man.”

The county has a precedent-setting history of using such evidence. In 1989, the district attorney’s office became the first in the state to use DNA to win a murder conviction, after presenting evidence that defendant Lynda Axell’s hair genetically matched strands found in the clenched fist of a slain burger stand worker.

Those tests were conducted by an out-of-state lab. Today, the county lab handles almost all requests from prosecutors and seven police agencies and for considerably less money. The county has estimated its cost per sample at $65, while private labs charge $1,000 or more.

As they look to the future, scientists hope technological advances will allow DNA tests to be completed faster. They grumble at plot lines on television dramas that falsely suggest tests can be turned around in a matter of hours.

Meanwhile, law enforcement officials hope more cases will be solved in the years ahead as genetic profiles are entered into state and federal databases.

Suzette Sanders, a forensic scientist and former police officer who works at the lab, has entered about 100 profiles into the Combined DNA Index System, or CODIS, which is available to law enforcement agencies across the nation. The system has yielded four hits so far and led to the arrest of one homicide suspect.

“This really does give us the power to solve those cases that otherwise maybe wouldn’t be solved,” she said.