In questioning so heated the jury had to be removed from the courtroom, defense lawyers in Scott Peterson's murder trial Thursday attacked the admissibility of the prosecution's key piece of physical evidence — a single strand of dark hair.
Detectives have testified they collected a single strand of hair from a pair of pliers found on Peterson's boat, which prosecutors allege he used to ferry Laci Peterson's body onto San Francisco Bay.
But when prosecutors opened an evidence envelope several months later, two hairs were present. That led defense lawyer Mark Geragos to suggest police botched the collection process — possibly even contaminating the evidence.
Prosecution witness Rodney Oswalt, a criminalist with the California Department of Justice, testified Thursday that the hairs were likely two separate strands — not, as the prosecution had suggested during a preliminary hearing, a single hair that had broken in two.
Cross-examination of Oswalt became so intense that the judge removed the jury from the courtroom. Geragos then asked the judge to allow him to tell jurors the prosecution's theory "changes as it blows in the wind."
"If he's going to testify that there were two hairs then that raises the specter once again there was a break in the chain of custody," Geragos argued. "I think the jury should be privy to the fact that it was the DA's contention at the preliminary hearing that this hair broke in half."
The judge would not allow it, but said Geragos could simply question Oswalt about the hairs.
"Did you ever tell the DA that it was one hair that broke in half?" Geragos asked Oswalt.
"Did I tell them? No," Oswalt replied.
Earlier, Oswalt testified the two hair fragments "could have" come from Laci Peterson. He also described the condition of the fragments, telling prosecutors the hair "appeared to be broken or torn at the end," adding "it wasn't cleanly cut off."
"It looked as though it had been torn or crudely sheered," he said.
He also said one end was "mashed." "You don't normally see that in hair that has been brushed or combed," Oswalt said.
Prosecutors allege Peterson killed his pregnant wife in their Modesto home on or around Dec. 24, 2002, then drove her body to the bay and dumped her overboard from his small boat. Her remains and that of the couple's fetus washed ashore near where Peterson claims he was fishing on Christmas Eve 2002.