Two strands of dark hair found on Scott Peterson’s boat could not have come from him and are consistent with strands taken from his slain wife’s hairbrush, a prosecution expert testified Wednesday.
Karen Korsberg, an FBI trace evidence expert, took the stand as testimony turned to the hairs, a key piece of physical evidence to bolster the prosecution’s contention that the boat was used to dispose of Laci Peterson’s body.
Korsberg said her tests excluded the possibility that the hairs, found on a pair of pliers on the boat, came from Scott Peterson. She said they were consistent with the hair on his pregnant wife’s brush.
Laci Peterson, eight months pregnant, vanished just before Christmas 2002 from the couple’s home in Modesto. Her remains and that of her fetus were found on the shore of San Francisco Bay several months later.
On cross-examination, Korsberg acknowledged that she was unaware of a pubic hair collected from duct tape found on Laci Peterson’s remains and never compared that to the samples she was given from Laci’s hairbrush.
Korsberg said she forwarded the two hairs to another FBI lab for further testing, a technique known as mitochondrial DNA. Defense lawyers have attacked the mitochondrial testing, one calling it the unreliable subject of “raging debate” among scientists.
Defense attacks evidence collection
Defense lawyers also have attacked the way police collected the hairs from the pliers. Detectives testified that they took one hair from the pliers but months later discovered two strands inside the evidence envelope.
Sarah Yoshida, a state criminalist, testified Tuesday that she found no signs of blood or tissue on two pairs of Peterson’s pliers seized by police, including the tool where the hair was discovered. Under cross-examination, she said the pliers were rusty and showed no signs of recent use.
Prosecutors say the hair found on the boat is significant because, they contend, Laci Peterson was never on the boat and was even unaware her husband had bought one.
Prosecutors allege Peterson killed his wife in their Modesto home on or around Dec. 24, 2002, then drove to San Francisco Bay and dumped her body from his boat. Peterson says he went on a fishing trip that day and returned home to discover that his wife was missing.
Defense lawyers contend someone else abducted and killed Laci, then framed their client after learning of his widely publicized alibi.
Prosecutors claim leads were exhausted
Also Tuesday, prosecutors presented evidence intended to bolster the prosecution’s contention that police exhausted all leads in their investigation of Laci’s disappearance. Two investigators said they pursued a tip that Laci Peterson was being held in a rural area about 30 miles from her home.
Modesto police officer Eric Beffa testified about an anonymous tip police received in early January 2003, just weeks after the disappearance, that Laci was being held captive near Tracy, a suburb west of Modesto.
On cross-examination, defense lawyer Mark Geragos noted the tip also included mention of a van.
Neighbors of the Petersons told police they saw a “suspicious” van with three men in the area around the time Laci Peterson vanished. It’s a detail Geragos has continually brought up as he works to create reasonable doubt.