Defense Grills Top Peterson Cop

The lead detective assigned to investigate Laci Peterson's disappearance backed up a key defense theory Monday by testifying that the pregnant schoolteacher had planned to walk the couple's dog the morning she vanished.

Modesto police Detective Craig Grogan has spent a week recounting why authorities maintain Scott Peterson is the only person who could have killed his wife.

Defense attorneys began their cross-examination Thursday and continued Monday. They are attempting to show police focused too hastily on Peterson.

Prosecutors allege Peterson killed Laci on or around Dec. 24, 2002, in their Modesto home, then dumped her weighted body into San Francisco Bay. Her remains — and that of her fetus — washed up in April 2003, not far from where Peterson launched his boat that Christmas Eve morning for what he claims was a solo fishing trip.

Defense lawyers maintain someone else abducted and killed Laci while she walked the couple's dog in a nearby park. The dog, McKenzie, was found by a neighbor running loose in the street at about 10:18 a.m. the morning Laci vanished, according to previous testimony.

Prosecutors claim Laci had stopped walking the dog weeks earlier at her doctor's request, and that Peterson set the dog loose to make it appear as it someone else abducted her.

But Grogan acknowledged Monday that Scott Peterson told police on the first night of the investigation that Laci had planned to walk the dog that morning. Her mother also reiterated the same story a few days later.

Sharon Rocha, Laci's mother, told Grogan that Laci walked the dog every morning, Grogan testified.

Defense attorney Mark Geragos also noted that Peterson was cooperative from the beginning, even as police sought search warrants for Peterson's home and warehouse where he stored the boat prosecutors allege he used to dispose of his wife's body.

"He basically said, 'If you had asked me I would have let you search (the warehouse)' ... is that correct?" Geragos asked.

"Yes, he said something like that," Grogan said.

At the onset of his cross-examination Thursday, Geragos quickly got Grogan to acknowledge that Peterson had no prior criminal history and had never laid a hand on his wife before she was reported missing.

The detective also agreed that as the investigation unfolded, the Petersons' friends were all very supportive of the 31-year-old former fertilizer salesman.

As the cross-examination of Grogan entered its second day, Geragos began to point out for jurors all the evidence police couldn't find that would implicate Peterson in the killings — no murder weapon, no crime scene, no cause of death and no direct witnesses.

Geragos also noted that police never checked the Petersons' home for fingerprints, implying they may have found the "real killer's" prints in the home.

Grogan explained that "there was no indication" anyone had broken into the home or that anything in the house had been moved or altered, so police felt a check for fingerprints was not necessary.

Judge Alfred A. Delucchi told jurors last week prosecutors intended to wrap up their case by this Thursday — after 18 weeks of testimony from more than 160 witnesses.

Peterson faces the death penalty or life without parole if convicted.