Judge to decide if DNA test in murder trial gets hearing

Lawyers for Peter Derks, the man accused of killing a woman in Montana de Oro in 1985, are trying to prove the prosecution's test is scientifically questionable and unfounded



Within the next two weeks, Superior Court Judge Dodie Harmon will decide if the process state investigators used to test DNA from a 1985 murder is scientifically recognized. If she rules that it is, as she is expected to do, it will clear a major roadblock for prosecutors who have charged Peter Anthony Derks with raping and killing a college student in Montana de Oro 25 years ago.

Derks' lawyers have asked Judge Harmon for a "Kelly hearing," where the prosecution would have to prove that the science they're using to link DNA found at the crime scene to Derks is reliable and has been accepted in its scientific community.

To bolster their side, Derks' lawyers have filed 30 exhibits - more then 2,000 pages - of DNA-related information in court. One of those lawyers, Pierre Blahnik, spoke in court for almost an hour on Wednesday, weaving a complicated argument as to why Harmon should allow the Kelly hearing.

It wasn't about deception, Blahnik said. "This is a scientific process [and] it's a source of disagreement among scientists," he said about the method used.

While he spoke, other public defenders and deputy district attorneys sat in the audience and quietly watched. Nearby, the parents and sister of the murder victim, Mary Catherine Waterbury, sat in silence.

Dressed in prison orange, Derks sat alone in the jury box, his head slightly tipped back and his eyes half closed. His shoulder-length gray hair was combed back over the top of his head; he kept his fingers intertwined in his lap through the hearing. Aside from a brief smile at his lawyers at one point, he showed no emotion.

Deputy District Attorney Tim Covello followed Blahnik's arguments, and briefly countered the defense's points. As Blahnik rebutted, and tried to respond to the many questions Harmon broke in to make, his answers and counterpoints were emphatic to the point of being emotional at times.

Harmon was willing to wait and go over the arguments before she decided.

"I can tell you that all the research so far tells me this is not a Kelly hearing," she said. "Having said that, I can give you a ruling in two weeks."

Waterbury was 23 the afternoon she told her sister, a fellow local college student, that she was going to take pictures of the sunset at Montana de Oro. When she didn't return, friends and family called the police; two days later her body was found.

Gary Hoving, with the county Sheriff's Department, was one of the first deputies on the scene the morning of Oct. 19, 1985. Back then Hoving was a detective in the sheriff's crime lab; today he's a chief deputy. When he got to the park at about 10:30 a.m., he found Waterbury's yellow Volkswagen bus parked on the main road. Her body was close - about 200 yards off a nearby dirt road and between two clumps of bushes.

In recent court testimony, Hoving described the sad details of how she was found: face-down in the dirt, her blue T-shirt pushed up, her right leg folded against her side, a red sweatshirt knotted tightly around her neck. Nearby were her underwear and her jeans, one leg inside out.

The detectives covered the dead woman's hands with paper bags and taped them shut, hoping to preserve any evidence that might exist under her fingernails. They impounded her van and towed it to headquarters. And the coroner's staff took the body away.

There were two key people involved with the autopsy: The county's pathologist, Dr. David Lawrence, and Dr. Laura Slaughter, the chief medical director for SART, the county's Sexual Assault Response Team.

As Lawrence inspected Waterbury's body for a cause of death, he chronicled her injuries: a wound on her right ear, trauma on her neck from the sweatshirt, fingernail marks around her neck, a "tearing type wound" on her left breast, and other wounds consistent with sexual assault.

He also found sand in her trachea.

The sweatshirt wrapped around Waterbury ' s neck did not kill her. Instead, she struggled against her attacker, trying to breathe as she was held down, and suffocated in the park' s soft soil.

Dr. Slaughter's job was to record evidence of sexual assault, and part of that meant taking samples. Using medical swabs and microscope slides, Slaughter took biological samples from different areas of the body and then sealed those samples in what's called a SART kit, which was then transferred to the Sheriff Department's evidence room. Under oath, deputies swear that's where it sat, unaltered, for the next 18 years.

In court testimony this year, Sgt. J. Donovan, with the Sheriff's Department, says that in June 2003 his superiors told him to sign out the SART kit and send it to a California Department of Justice lab in Goleta. As Donovan explained it, the state's Attorney General was conducting a "cold case program" where departments with unsolved cases could bring in evidence that might have DNA, and they would be given priority.

Donovan testified that most of the evidence his department sent had no "evidenciary value." But one swab allegedly did. According to court testimony, the lab's technician, Roland Chang, was able to take biological material from the swab and separate it into two cell types: male and female. Deputies say that Chang extracted DNA from the male cells, ran it through a database of DNA from California felons, and found a match - a match with allegedly a 20-billion-to-1 chance of being incorrect.

Peter Derks - who was convicted of rape in Texas in February 1973 and convicted of assault with a deadly weapon after attacking a woman in Montana de Oro in May 1987 - was arrested and charged with one count of murder and two counts of rape. He has been held in county jail ever since.

Staff Writer Abraham Hyatt can be reached at

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