REDWOOD CITY, Calif. -- Prosecutors yesterday attacked a witness critical to Scott Peterson's defense who nervously conceded he made an assumption as he calculated when Laci Peterson's fetus died.
Dr. Charles March, a gynecologist asked by the defense to examine prosecution witnesses' findings and Laci Peterson's medical records, testified that based on bone measurements of the dead fetus and reviewing ultrasounds taken of her, the fetus probably died Dec. 29, 2002, at the earliest, five days after the pregnant schoolteacher vanished.
That would undercut the prosecution's contention that Scott Peterson murdered his wife on or around Dec. 24, then dumped her body into San Francisco Bay. But March also said he based his findings, in part, on anecdotal evidence of when Laci Peterson may have discovered she was pregnant.
According to previous testimony, Laci Peterson told one of her friends on June 9, 2002, that she was pregnant. Under cross-examination, March acknowledged he inferred from that information that Laci Peterson had just found out she was pregnant based on a home test June 9 because, he said, she would likely have told her friend about it immediately.
"Where in the medical records does it talk about Laci Peterson using a pregnancy test on June 9?" prosecutor Dave Harris asked.
"Nowhere," March replied, becoming obviously flustered, shifting nervously in his seat and biting his lower lip.
"So you're making an assumption to form a medical opinion, isn't that correct?" Harris asked.
"Based on 30 years of being a doctor . . . that's a pretty good assumption," March said.
Defense lawyer Mark Geragos promised jurors during his opening statement that he would prove the fetus died after Laci Peterson vanished.
Judge Alfred A. Delucchi told jurors yesterday they would be sequestered for deliberations set to begin Nov. 3. They have been free to go home throughout the duration of the five-month old trial.